1
2
3
4
5
6
7
8
9
What is total AM transmitter power if carrier power 100W modulated with modulation index m=0.7 A
149W
B
170W
C
124.5W
D
135W
What is percentage power saving if AM transmitter with modulation index m=0.5 is replaced by SSBSC transmitter with same modulation index A
83.30%
B
94.40%
C
96%
D
88.88%
In television 4:3 represents A
Interlace ratio
B
Form factor
C
Aspect Ratio
D
None of above
To permit selection of 1 out of 32 equi-probable events, number of bits required is A
32
B
8
C
5
D
4
Value of Intermediate frequency (IF) for FM receiver is … A
455 KHz
B
10.7 MHz
C
70 MHz
D
118.7 MHz
Amplitude limiter is used in FM receiver because A
It limits audio signal
B
It prevents overloading
C
It removes distortions
D
It removes amplitude variations
Which circuit is used in FM receiver but not in AM Receiver A
RF amplifier
B
Mixer
C
Amplitude limiter
D
AGC
Demerits of balance slope detector for FM receiver A
Poor linearity
B
No amplitude limiting
C
Tuning is difficult
D
All of above
AM receiver is tuned to 600 KHz with quality factor Q=100, IF value 455 KHz. Image rejection in dB
10
11
12
13
14
15
16
17
18
A
-20dB
B
-30dB
C
-35.5dB
D
-46.5dB
Crystal oscillator can be used in A
Varactor diode modulator
B
Transistor reactance modulator
C
Armstrong modulator
D
FET reactance modulator
Bit rate is ___________ Baud rate in QPSK system A
equal to
B
three times
C
two times
D
less than
What is the separation of phasors in 8-PSK system? A
900
B
450
C
22.50
D
150
Number of possible symbols in QAM system are A
2
B
4
C
8
D
16
Muting (squelch) circuit is basically… A
Low pass filter circuit
B
High pass filter circuit
C
Level activated switch
D
Frequency converter circuit
Double conversion receiver has A
Two RF amplifier stage
B
Two IF
C
Two detectors
D
Two audio amplifier stage
Sampling rate required to sample CD quality audio signal is …. A
8000 samples/sec
B
16000 samples/sec
C
20000 samples/sec
D
44100 samples/sec
Oversampling results into …. A
Large transmission bandwidth
B
More transmission power
C
Low SNR
D
Distorted speech
B
PWM System
Synchronization is necessary in … A
PAM system
C 19
20
21
22
23
24
25
26
27
PPM System
D
None of above
Nyquist bandwidth required to transmit information signal with bandwidth 10 KHz coded with total 128 quantization levels is … A
1280 Kbps
B
140 Kbps
C
70 Kbps
D
64 kbps
Companding is used to … A
Save transmission bandwidth
B
Remove noise
C
Achieve uniform SNR for all amplitudes
D
Achieve amplitude limiting
Uplink frequency range for GSM-900 band is… A
890-915 MHz
B
935-960 MHz
C
890-960 MHz
D
890-910 MHz
Duplex distance for GSM-1800 band is … A
45 MHz
B
95 MHz
C
25 MHz
D
50 MHz
Following is not component of GSM architecture…. A
Main switching center
B
Base station controller
C
Master station controller
D
Base trans receiver
5
If PN chip rate is 30x10 and message bit rate is 1000, Processing gain of DSSS system is .. A
3000
B
6000
C
30000
D
60000
Frequency range of Ku Band is … A
2 GHz - 4 GHz
B
4 GHz - 8 GHz
C
8 GHz - 12 GHz
D
12 GHz - 18 GHz
What is the cut-off frequency of ractangular waveguide having dimension 1.5cm x 1 cm in dominant mode TE10. A
1 GHz
B
5 GHz
C
10 GHz
D
15 GHz
Data rate at the output of GSM speech codec is …
28
29
30
31
32
33
34
35
A
104 kbps
B
64 kbps
C
13 kbps
D
2.2 kbps
CELP Speech coder is based on …. A
Waveform coding
B
Parametric coding
C
Channel coding
D
Hybrid coding
Improvement in SNR of uniform PCM system if 9 bit is used instead of 8 bit in quantization… A
1 dB
B
3 dB
C
6 dB
D
12 dB
In adaptive delta modulation … A
Step size is variable
B
Slope over load error eliminated
C
Granular noise is less
D
All of above
The spectral density of real valued random process has A
an even symmetry
B
a conjugate symmetry
C
an odd symmetry
D
no symmetry
The stationary process has A
Ensemble average equal to time average
B
All Statistical properties dependent on time
C
All statistical properties independent of time
D
Zero variance
A random process obeys Poisson's distribution. It is given that the mean of the process is 5. Then the variance of process is .. A
0
B
0.5
C
1
D
5
Thermal noise is independent of … A
Temperature
B
Center frequency
C
Bandwidth
D
Boltzmann's constant
A system has receiver noise resistance of 50 Ω. It is connected to an antenna with input resistance of 50 Ω. Noise figure of the system is .. A
1
B
2
C 36
37
38
39
40
41
42
43
0
D
None of above
Calculate output SNR in dB for three identical links. SNR of one link 60 dB A
57 dB
B
180 dB
C
51.23 dB
D
55.23 dB
Positive RF peak of AM signal rise to 12V and drop to minimum value of 4V. Modulation index is … A
0.25
B
0.33
C
0.5
D
0.66
Resonant frequency of RF amplifier is 1 MHz, bandwidth is 10 KHz. Q factor will be …. A
0.1
B
10
C
50
D
100
Balance modulator is used to generate … A
AM Signal
B
DSBSC Signal
C
PM Signal
D
PWM Signal
Maximum modulating frequency in AM system increases from 10 KHz to 20 KHz, Modulation index .. A
doubled
B
halved
C
remains constant
D
increase by 10
Primary function of multiplexing in communication system A
To select one radio channel from a wide range of transmitted channels
B
C
To reduce the bandwidth of a signal.
D
To allow a number of signals to make use of a single communications channel To match the frequency range of a signal to a particular channel.
Optical fiber uses ______ portion of Electromagnetic waves A
UHF
B
Ultraviolet
C
Between Infrared and Ultraviolet
D
Infrarred
Glass fiber has core refractive index n1=1.5 and cladding refractive index n2=1. Multipath dispersion would be …. (c=3x108 m/s) A
2.5 ns/m
B
2.5 µS/m
C 44
45
46
47
48
49
50
51
52
5 ns/m
D
5 µS/m
In CDMA systems A
Entire bandwidth can be used at a time
B
Entire bandwidth is used on time sharing basis
C
Entire bandwidth is divided into narrow bands
D
None of above
Following is not usual classification of optical fiber A
Single mode step index
B
Multi-mode step index
C
Multi-mode graded index
D
Single mode graded index
The energy gap Eg of PIN Photo detector should be _____photon energy of light (hf) A
Equal to
B
Smaller than
C
Greater than
D
Independent of
Numerical aperture (NA) and acceptance angle θ of fiber optic cable related by equation A
NA=sinθ
B
NA=tanθ
C
NA=sin-1θ
D
NA=(1-sin2θ)1/2
What is total SSB transmitter power if carrier power 10W modulated with modulation index m=0.5 A
0.625 W
B
1.25 W
C
2.5 W
D
5W
What is total SSB transmitter power if carrier power 10W modulated with modulation index m=0.5 A
0.625 W
B
1.25 W
C
2.5 W
D
5W
Cluster of cells is the collection of adjacent cells with A
Same operating spectrum
B
Different operating spectrum
C
both A & B
D
None of above
In GSM system case 1: cluster size N=7 case 2: cluster size N=19 A
Case 1 has more SIR
B
Case 2 has more SIR
C
Case 1 and Case 2 has equal SIR
D
No effect of N on SIR
In GSM system case 1: cluster size N=7 case 2: cluster size N=19
53
54
55
56
57
58
59
A
Case 1 has more channel capacity
B
Case 2 has more channel capacity
C
Case 1 and Case 2 has equal Channel capacity
D
No effect of N on channel capacity
In AM systems if modulation index increases from 0.5 to 0.75… A
Bandwidth increases by 1.5
B
Bandwidth decreases by 1.5
C
Bandwidth remains constant
D
None of above
In FM system, if modulation index increases from 5 to 10 …. A
Transmission power doubles
B
Transmission power halved
C
Transmission power 1.41 times
D
Remains same
In GSM system 5 MHz bandwidth is allocated to network operator, Assuming frequency reuse factor 1/5, maximum number of simultaneous channels that can exists in one cell is … A
15
B
25
C
40
D
200
The main objective of cell in cellular mobile system is A
hand-off possibilities
B
frequency resue
C
simple modulation requires
D
higher bandwidth
Which of following mobile systems is second generation mobile communication system? A
AMPS
B
GSM
C
IMT-2000
D
NAMTS
Basic purpose of cell splitting in GSM mobile systems is .. A
Reduce handoffs
B
Reduce channel capacity
C
Increase channel capacity
D
Reduce bandwidth requirement
Frequency reuse ratio in mobile communication is given by… A C
60
61
Q=R/D 2
Q=D/R
B
Q=RxD
D
Q=D/R
A cellular system has 12 macro-cells with 10 channels per cell. Each macro cell is splitted into 3 microcells. Find out total available channels after splitting A
40
B
120
C
360
D
30
Major development under the way in the field of telecommunications..
A C 62
65
66
67
68
69
70
Fixed and mobile convergence Satellite communication
GPRS CDMA2000 1xRTT
B D
EDGE IS95
Which one of following enhances data capability of 2G mobile network? A C
64
B D
One of following is not part of 2.5G technologies in mobile communication A C
63
Data & Voice convergence Internet
TACS GPRS
B D
GSM ISDN
Population inversion phenomenon found in A
LED
B
Photodiode
C
LASER
D
FET
Optical fiber having core refractive index n1=1.4 and cladding refractive index n2=1.05. Its numerical aperture will be … A
0.926
B
0.8
C
0.35
D
0.15
Normalized frequency of step index fiber is 28 at 1300 nm wavelength. What are total app. number of guided mode supported by fiber? A
50
B
100
C
200
D
400
The SAFER+ algorithm is used to provide security in which wireless technology? A
Bluetooth
B
ZigBee
C
UWB
D
WiMAX
Which numbers appear in the International Mobile Equipment Identity (IMEI)? A
Mobile Country Code
B
Mobile Network Code
C
Equipment Serial Number
D
None of above
The term STN (Super Twisted Nematic) refers to _________. A
The layered structure of the display
B
The nature of the liquid crystal itself
C
The control signal applied to the display
D
The application of display backlighting
Disadvantage of STN (Super Twisted Nematic) is …. A
Consumes more power
B
Operates slowely
C 71
72
73
74
75
Higher cost
D
Less life time
For random variable x, probability density function p(x) is given by: p(x)=1/2 for -1 ≤ x ≤ 1 and p(x)=0 otherwise. Mean and variance respectively …. A
1/2 and 2/3
B
1 and 2/3
C
1 and 4/3
D
2 and 4/3
Probability density function of the envelope of narrowband Gaussian noise is… A
Rayleigh
B
Poisson
C
Gaussian
D
Rician
Spectral density expresses …. A
Average voltage
B
Average current
C
Average frequency
D
Average power as a function of frequency
Aperture effect in flat top pulses is reduced by using A
Integrator
B
Differentiator
C
Predictor
D
Equalizer
In PCM system, quantization noise depends on … A
76
77
78
79
Sampling interval B Number of quantization levels Frequency of information C D None of above signal In PCM system, sampling rate is determined by A
Parsevals Theorem
B
Nyquist Theorem
C
Fourier Transform
D
Hysenberg Theorem
Frequency range of telephonic quality speech is A
20 Hz to 20 KHz
B
500 Hz to 10 KHz
C
300 Hz to 3.4 KHz
D
300 Hz to 5 KHz
Range of Very High Frequency (VHF) is A
3-30 MHz
B
30-300 MHz
C
300-3000 MHz
D
3-30 GHz
Process of transmitting two or more information signals on same channel is called … A
Modulation
B
Multiplexing
C 80
81
82
83
84
85
86
87
88
Detection
D
Telemetry
Which one of the following requires synchronizing signal? A
PPM
B
PWM
C
PAM
D
All of above
Quantization noise occurs in… A
PWM
B
PPM
C
PCM
D
AM
Which one of following system is digital? A
PAM
B
PWM
C
PCM
D
AM
Which one of following pulse modulation system is analog? A
PWM
B
PCM
C
DM
D
ADM
In delta modulation, granular noise occurs when modulating signal A
remains constant
B
increases rapidly
C
decreases rapidly
D
None of above
For uniform quantization, 32 levels can be represented by A
4 bit
B
5 bit
C
8 bit
D
32 bit
In QAM system following both identity are varied A
Amplitude and frequency
B
Frequency and phase
C
Amplitude and Phase
D
Baud rate and phase
In PCM systems, if transmission path is long…. A
High power transmitter are used
B
Sensitive receivers are used
C
Repeaters are used
D
Pulse amplitude increases
An amplifier having noise figure of 20 dB and available power gain of 15 dB followed by mixer circuit having noise figure of 9 dB. The overall noise figureas referred to input in dB is…
89
90
91
92
93
94
95
A
21.53
B
11.07
C
10.44
D
0.63
A parallel tuned circuit is resonated with 200 MHz with Q of 10 and capacitance of 10 pF. Temperature of circuit is 170 C. What is noise voltage observed across circuit by wideband voltmeter? A
1 µV
B
2 µV
C
8 µV
D
16 µV
What is the relation between Noise Bandwidth and 3-dB bandwidth in ideal systems? A
BN > B3dB
B
BN = B3dB
C
BN =0.5* B3dB
D
BN = 0.5*π*B3dB
What is the relation between Noise Bandwidth and 3-dB bandwidth in Low pass filter? A
BN > B3dB
B
BN = B3dB
C
BN =0.5* B3dB
D
BN = 0.5*π*B3dB
What is internal noise power (Pn) of microwave amplifier operating with a bandwidth of 500 MHz and noise figure of 2.5 dB? A
0.5 pW
B
0.557 pW
C
1 pW
D
1.557 pW
Noise voltage source has resistance of 10 Ω. Its power density spectrum is 0.24x10-5. Corresponding available power density is .. A
2.6x10-5
B
0.025
C
26x10-5
D
6x10-8
If resistance value doubled and temperature maintained at constant level, available thermal noise power per unit bandwidth will A
remains constant
B
Increase two times
C
Increase four times
D
Decrease to half
What will be thermal noise voltage developed across resistor of 10 Ω. The Bandwidth of measuring instrument is 1 MHz. Ambient temperature 270 C A
0.40 µV
B
1.28 µV
C
0.16 µV
D
1.19 µV
96
97
98
99
100
101
102
103
Which one of following is suitable detector to detect information signal from modulated signal (5+10cosωmt)coswct A
Envelope detector
B
Synchronous detector
C
Ratio detector
D
None of above
Plot of modulation index versus carrier amplitude in FM yields …. A
Horizontal line
B
Vertical line
C
Parabola
D
Hyperbola
Image rejection in super-heterodyne receiver occurs at .. A
RF Stage
B
Mixer Stage
C
IF stage
D
Detector stage
Modulation index of AM wave changes from 0 to 1, transmitter power … A
Increase by 100%
B
Increase by 50%
C
Increase by 25%
D
Does not change
Which one of following modulation scheme requires minimum bandwidth and minimum power? A
VSB
B
SSBSC
C
DSBSC
D
AM
For FDM systems used in telephone, which of the following system used A
AM
B
FM
C
SSB
D
DSBSC
1 MHz sinusoidal carrier is amplitude modulated by symmetrical square wave of period 100 µS . Which of the following frequencies will not present in the modulated signal? A
990 KHz
B
1010 KHz
C
1020 KHz
D
1030 KHz
1 MHz sinusoidal carrier is amplitude modulated by sine wave of period 100 µS for one cycle . Which of the following frequencies will not present in the modulated signal? A
990 KHz
B
1000 KHz
C
1010 KHz
D
1020 KHz
104
105
106
107
108
109
110
111
In amplitude modulation system, total power is 600 W and power of carrier is 400 W. Modulation index is… A
0.25
B
0.5
C
0.75
D
1
Carrier is amplitude modulated by three message signal with modulation index 0.2, 0.4 and 0.5 What is total modulation index? A
1.1
B
0.67
C
0.55
D
0.25
Total rms antenna current of AM radio transmitter is 6 A. It reduces to 5 A when modulating signal is removed. What is modulation index? A
0.94
B
0.83
C
0.69
D
0.33
AM signal has carrier power 1 KW. In each sideband, there is 200 Watt. What is modulation index? A
0.201
B
0.404
C
0.8
D
0.894
In low level amplitude modulation, amplifier following modulated stage must be .. A
Non-linear amplifier
B
Linear amplifier
C
Class C amplifier
D
Harmonic amplifier
FM signal with modulation index 10 is passed through frequency tripler, output signal have modulation index A
3.33
B
10
C
30
D
10
Bandwidth of FM signal does not depends on… A
Modulating frequency
B
Carrier frequency
C
Maximum amplitude of modulating signal
D
Peak frequency deviation
Following problem will occur if we keep value of IF too high in receiver A
Poor adjacent channel rejection
B
Poor sensitivity
C
Tuning is difficult
D
Poor fidelity
112
113
114
115
116
117
118
119
120
Following diode is used in AM detector circuit A
Silicon diode
B
Point contact diode
C
Tunnel diode
D
PIN diode
Standard bandwidth of IF amplifier in FM receiver is .. A
10.7 MHz
B
50 KHz
C
100 KHz
D
200 KHz
Basic reason behind linearity of phase discriminator is… A
Tuned circuit is used
B
Primary to secondary phase relationship is linear
C
RFC is used
D
Parallel combination of RC
Following FM detector uses large capacitor to achieve amplitude limiting A
Diode detector
B
Phase discriminator
C
Ratio detector
D
PLL Detector
UHF 900MHz frequency band is used in cellular mobile communication because…. A
Below 900 MHz, band is not available
B
Good Sky wave Propogation at 900 MHz.
C
Line of sight and reflected signal ensure the reception at mobile handset
D
None of above
GSM cellular mobile communication system uses … A
CDMA and FDMA
B
FDMA and TDMA
C
Only FDMA
D
Only TDMA
WLAN services uses A
Long distance communication at high data rate
B
Short distance communication at high data rate
C
Long distance communication at low data rate
D
Short distance communication at low data rate
As per IEEE 802.11g standard WLAN devices which are 50 meter apart can send and receive data up to …. A
64 kbps
B
2 MBPS
C
11 MBPS
D
54 MBPS
GPRS is….
121
122
123
124
125
126
127
128
A
Circuit switched and packet switched service
B
Packet switching for mobile users for data transfer
C
Voice telephony services
D
useful for sending SMS
UMTS offers data speed … A
384 kbps on move and 2.048 Mbps on stationary
B
64 Kbps on move and 1 Mbps on stationary
C
2.1 MBPS on move and 8 MBPS on stationary
D
None of above
IEEE 802.16 WiMAX standard offers maximum data rate …. A
2 MBPS
B
8 MBPS
C
54 MBPS
D
75 MBPS
Bluetooth module communicates using …. A
transmitter
B
receiver
C
radio module
D
transponder
IEEE 802.15.1 Bluetooth system has typical frequency hop rate of ______ hops per second A
512
B
800
C
1600
D
3200
IEEE 802.11 WLAN physical layer with 2 MBPS with base band modulation DSSS uses carrier modulation scheme _____________. A
BPSK
B
QPSK
C
DQPSK
D
QAM
The size of file transferred in 10 seconds using WLAN system operating at 2Mbps considering ideal transfer data rate. A
2 MB
B
2.5 MB
C
10 MB
D
20 MB
Which technology is used by IEEE 802.15.1 WPAN standard to separate piconets A
DSSS
B
OFDM
C
FHSS-CDMA
D
FHSS-TDMA
In close loop power control, base station sends power control messages to mobile handset at every ….
129
130
131
132
133
134
135
136
137
A
1 ms
B
10 ms
C
100 ms
D
500 ms
WCDMA uplink uses spreading factor up to …. A
16
B
32
C
64
D
512
Data modulation used in WCDMA for reverse channel is … A
BPSK
B
QPSK
C
DQPSK
D
QAM
WCDMA uses chip rate of …. A
2 Mcps
B
8 Mcps
C
3.84 Mcps
D
16 Mcps
Voice encoding technique used in WCDMA … A
LPC
B
RELP
C
Adaptive CELP
D
DPCM
Maximum EIRP for class-III mobile phone in WCDMA is … A
+23 dBm
B
+13 dBm
C
+9 dBm
D
+3 dBm
After spread spectrum modulation, bandwidth of spreaded signal A
remains constant
B
increases
C
increases significantly
D
decreases
Minimum Eb/No value required for proper system operation depends on .. A
Performance of coding method
B
Bit error rate
C
Tolerance of digitised voice
D
All of these
CDMA IS-95 technology uses one of following multiple access technique A
FDMA
B
FHSS
C
DSSS
D
THSS
In DSSS system, code rate is 48 Mcps and information signal rate 4.8 Kbps, Processing gain in dB is …
138
139
140
141
142
143
144
145
A
4.8 dB
B
48 dB
C
40 dB
D
60 dB
In FHSS system total bandwith is 500 MHz, individual channel bandwidth is 5 KHz. What is processing gain in dB? A
5 dB
B
50 dB
C
4 dB
D
40 dB
Each carrier of CDMA IS-95 carrier occupies bandwidth of A
200 KHz
B
600 KHz
C
1.25 MHz
D
10 MHz
Once link with nearest base station is established in CDMA, open loop power setting is adjusted in 1 dB increments after every ______ by command from base station. A
1 second
B
1.25 second
C
10 ms
D
1.25 ms
MAHO is implemented in mobile communication in order to A
reduce co-channel interference
B
reduce transmission power
C
reduce inter-cell interference
D
reduce near-far problem
Which one out of following offers high spectrum efficiency with constant amplitude ? A
FSK
B
QPSK
C
GMSK
D
QAM
The frequency hoping system used in GSM allows to change transmission frequency once in every ______ . A
1.25 ms
B
120 ms
C
4.615 ms
D
125 µs
Modulation data rate in GSM is …. A
200 kbps
B
270.833 kbps
C
64 kbps
D
2 Mbps
B
1.35 bps/Hz
Spectrum efficiency in GSM is …. A
1 bps/Hz
C 146
147
148
149
150
151
152
153
2 bps/Hz
D
4 bps/Hz
Grey list in mobile communication means … A
Mobile numbers are VIP
B
Mobile numbers are not allowed permanantly
C
Mobile numbers are not allowed momentarily
D
Mobile purchased without bills
Broadcast Control Channel (BCCH) is by BTS to broadcast …. A
Frequency of operation in cell
B
Channel availability
C
Congestion information
D
All of above
The number of time slots available per RF channel in GSM system is .. A
3
B
4
C
8
D
16
The standard interface that connects BTS to BSC is called … A
Um Interface
B
A-bis
C
A
D
D
The difference in free space propagation loss between two location 2 km and 8 km from transmitter is … A
3 dB
B
6 dB
C
12 dB
D
15 dB
Wireless medium compared to wired medium A
Quite reliable for voice and data communication
B
Not reliable for voice and data communication
C
Offers more bandwidth
D
Requires less power
In mobile radio propagation path loss exponent γ is … A
2
B
3
C
4
D
5
Cellular network is reconfigured with frequency reuse pattern of 7 instead of 4. Increase in overall system capacity is approximately A
28 times
B
7 times
C
4 times
D
1.7 times
154
155
156
157
158
159
160
161
Cells using same set of frequencies are called A
neighboring cells
B
adjacent channel cells
C
Co-channel cells
D
Clusters
The distance between the centers of two hexagonal cells, if radius of cell is 2 km A
√3
B
2√3
C
4√3
D
4
Mobile communication system is designed with cell size of 2 km2. Cluster size N=7. What is will be area of one cluster? A
3.5 km2
B
7 km2
C
14 km2
D
14√3 km2
Service area is covered with 10 clusters each having 7 cells in it. 16 channels are assigned to each cell. The number of channels per cluster are .. A
1120
B
112
C
70
D
None of above
Mobile communication system has an allocated number of 1000 voice channels. If service area is divided into 20 cells with a frequency reuse factor of 4. System capacity is …. A
1000
B
5000
C
10000
D
20000
In regular hexagonal geometry pattern, the number of cells in cluster formed by i=2 and j=2 are …. A
4
B
8
C
12
D
16
Propagation considerations recommends cell shape _____________ and for system design cell shape used is ______________. A
circular, circular
B
circular, hexagonal
C
hexagonal, hexagonal
D
hexagonal, circular
If cell site antenna height is doubled, there will be A
Reduction in path loss by 6 dB
B
Reduction in path loss by 3 dB
C 162
163
164
165
166
167
168
169
Reduction in path loss by 12 dB
D
No change in path loss
In wireless communication, transmitter power is 10W. Transmitter antenna gain is 3 dB. EIRP is. A
10 W
B
20 W
C
30 W
D
3.33 W
PLL can be used to demodulate A
AM
B
FM
C
PM
D
PCM
Two sinusoids of same amplitude and frequencies of 10 KHZ and 11 KHz are added together and applied to ideal frequency detector. Output of the detector is …. A
21 KHz sinusoid
B
1 KHz sinusoid
C
210 KHz sinusoid
D
1.1 KHz sinusoid
In commercial FM broadcasting, modulating frequency is limited to .. A
3.4 KHz
B
5 KHz
C
15 KHz
D
20 KHz
Modulating frequency in FM is increased from 10 KHz to 20 KH, bandwidth A
Gets doubled
B
Does not change
C
Increase by 20 KHz
D
Increase by 10 KHz
In single tone FM discriminator, So/No is A
proportional to deviation
B
proportional to cube of deviation
C
inversely proportional to deviation
D
Proportional to square of deviation
If modulating frequency is 20 KHz and peak frequency deviation is 50 KHz. Bandwidth of FM signal as per Carson's rule is …. A
40 KHz
B
90 KHz
C
140 KHz
D
200 KHz
Following is not advantage of FM over AM system A
Noise immunity
B
Fidelity
C
Capture effect
D
Sputtering effect
170
171
172
173
174
175
176
177
178
A sinusoidal signal with peak to peak amplitude 1.536 is quantized in 128 levels using mid-rise uniform quantizer. Quantization noise power is … A
0.12 V2
B
0.012 V2
C
0.0012 V2
D
0.000012 V2
Standard data rate of PCM for 30 channels is ….. A
64 KBPS
B
2.048 MBPS
C
4 MBPS
D
8 MBPS
The SQR for PCM if sinusoidal signal is quantized using 10 bit A
48 dB
B
56.8 dB
C
64 dB
D
67.78 dB
Pulse stuffing is used in A
Synchronous TDM
B
Asynchronous TDM
C
Any TDM
D
None of above
With compare to PCM system, delta modulation requires … A
lower sampling rate
B
low bandwidth
C
simple hardware
D
better SNR
Following is not ideal requirement from line codes A
Transmission bandwidth
B
large DC component
C
Favorable PSD
D
Timing recovery
Which one of following line code has no DC component and clock recovery property? A
Manchestor
B
NRZ
C
RZ
D
None of above
Which of the following gives maximum probability of error? A
ASK
B
BFSK
C
BPSK
D
DPSK
Output SNR of matched filter, fed at its input by a ractangular pulse of amplitude A and duration T is given by _________ considering N as noise PSD A
2AT/N
B
2A2T/N
C 179
180
181
182
183
184
185
186
AT
D
A/N
Main circuit used in DPSK modulator is … A
AND gate
B
OR gate
C
Ex-NOR gate
D
NAND gate
In digital communication system employing FSK, 0 is represented by sine wave of 10 KHz and 1 is represented by 25 KHz. These waveforms are orthogonal for bit interval of …. A
45 µs
B
50 µs
C
200 µs
D
250 µs
For a bit rate of 8 kbps, best possible values of transmitted frequencies in a coherent binary FSK systems are A
32 KHz and 40 KHz
B
8 KHz and 12 KHz
C
20 KHz and 40 KHz
D
16 KHz and 20 KHz
ASK, FSK and PSK are examples of A
Analog transmission of data
B
Digital to analog converter
C
Analog to Digital convertor
D
Analog modulators
Correlation receiver consists of … A
Adder and integrator
B
Multilier and integrator
C
Mutiplier and differentiator
D
Addre and differentiator
Baud rate of QPSK system is 100 then bit rate is … A
800
B
400
C
200
D
100
In digital communication system, the delay spreading along with fading causes _________and hence limits maximum symbol rate. A
Multipath fading
B
Doppler effect
C
higher bit rate
D
Intersymbol interference
Two main reasons for rapid fluctuations of the signal amplitude in mobile communication are .. A
Reflection and refraction
B
diffraction and scattering
C 187
188
189
190
191
192
193
194
Multipath fading and doppler effect
D
Blocking and shadowing
The average delay spread due to fading in urban area is ______ A
<0.1 µs
B
0.5 µs
C
3 µs
D
5 µs
A base station transmitter is operating at 900 MHz carrier frequency. Mobile moving at speed of 72 km/hr in a direction perpendicular to direction of arrival of signal. The receiver carrier frequency is … A
899.99 MHz
B
900.00006 MHz
C
900 MHz
D
900.03 MHz
Following channel passes all spectral components with approximately equal gain and linear phase without distortion. A
Rayleigh fading channel
B
Rician fading channel
C
Frequency selective channel
D
Flat channel
Due to presence of object between transmitter and receiver, following will happen. A
Scattering
B
Reflection
C
Shadow fading
D
Doppler effect
Rayleigh fading channel model characteristics is not applicable to … A
Multiple indirect path between transmitter and receiver
B
No distict line of sight path
C
Direct line of sight path
D
None of above
In wireless communication system, transmitter and receiver stations are located at distance of 10 km. transmission delay of signal typically … A
3.33 µs
B
33.3 µs
C
333.3 µs
D
3 ms
Optimal ration between the number of fixed and dynamic channels in hybrid channel assignment mainly depends on A
Availability of channels
B
Blocking probability
C
Traffic characteristics
D
System overheads
Cell site transmitter power incerases by 3 dB that means A
Transmitter power doubles
B
Transmitter power four times
C 195
196
197
198
199
200
201
202
Transmitter power 1000 times
D
None of above
Radius of split cell is one half of oringinal cell. Coverage area of split cell is __________ the coverage area of original cell. A
Half
B
Double
C
one fourth
D
Four times
In a flat operating terrain, doubling cell site antenna height results into .. A
3 dB increase in gain
B
6 dB increase in gain
C
9 dB increase in gain
D
8 dB increase in gain
Modem uses 4 different amplitudes and 16 different phases. Bits used to transmit each symbol are … A
4
B
5
C
6
D
8
Overall handoff delay in Mobile assisted hand off is about A
5 to 10 second
B
2 to 5 second
C
1 to 2 second
D
less than 1 second
Minimum required C/I is about _________ for narrowband digital cellular systems. A
3 dB
B
6 dB
C
9 dB
D
12 dB
If calling rate average is 20 calls per minute and average holding time is 3 minutes then offered traffic load in Erlang is …. A
6.66
B
30
C
60
D
360
One of following is not related to cyclic code. A
Error detection is simple
B
Look up table is required
C
Code is powerful and efficient
D
All of above
Binary symmetric channel transmitting 1's and 0's with equal probabilties has an error rate of 0.01. Channel transmission rate will be ... A
0.9
B
0.909
C
0.99
D
0.92
203
204
205
206
207
208
209
210
211
For telephonic quality speech channel, calculate information capacity of the telephone channel for SNR of 30 dB A
64 KBPS
B
32 KBPS
C
33.89 KBPS
D
16 KBPS
If receiver knows the message being transmitted by the transmitter, amount of information communicated is …. A
8 bit
B
4 bit
C
1 bit
D
0
What is amount of information in binary PCM with equal likelihood ? A
8 bit
B
4 bit
C
1 bit
D
0
A source produces four symbols x1,x2,x3 and x4 with probabilities 0.5, 0.25,0.125 and 0.125 respectively. Amount of information carried by symol x1 and x2 is … A
1 bit for both x1 and x2
B
2 bit for both x1 and x2
C
1 bit for x1 and 2 bit for x2
D
2 bit for x1 and 1 bit for x2
What is amount of information conveyed by symbol Z in bit ,if its probability is 0.25 A
0.25
B
5
C
1
D
2
Entropy of message source generating 4 messages with probabilities 0.5, 0.25, 0.125 and 0.125 is … A
1 bit/message
B
1.75 bit/message
C
2 bit/message
D
4 bit/message
Capacity of communication channel with a bandwidth of 4 KHz and 15 dB SNR is … A
4 kbps
B
8.02 kbps
C
20.11 kbps
D
32.40 kbps
In T1 systems, the frame synchronization code repeats at every A
1 µs
B
64 µs
C
125 µs
D
625 µs
Matched filter output over (0,T) to pulse waveform is …
212
213
214
215
216
217
218
219
A
e-T
B
e-Tsin(ht)
C
e-Tsin(t)
D
e-T/2sin(2ht)
Inter-symbol Interference can be reduced by following … A
Transmit sinc pulses instead of rectangular pulses
B
By using suitable pulse shaping techniques.
C
By reducing data transmission rate
D
All of above
Transversal equalizer uses tapped delay line to … A
Reduce ISI
B
Reduce data rate
C
Reduce bandwidth
D
None of above
Eb/No at the receiver input should be larger than ________ in order to recover error free data at receiver output. Eb=Received Signal and No/2 is power spectral density. A
0 dB
B
3 dB
C
-1.59 dB
D
1.33 dB
RC load for diode detector consists of a 1000 pF capacitor in parallel with 10 kΩ, maximum modulation depth that can be handled for sinewave of 10 KHz to avoid diagonal peak clipping. A
0.25
B
0.5
C
0.85
D
0.9
HDTV has aspect ratio A
4:3
B
16:9
C
9:16
D
3:4
As per new HDTV standard formats number of scan lines are … A
Interlace scan mode 1080
B
Progressive scan mode 780
C
Both A and B
D
None of above
In 1080i HDTV system, nummber of pixels in each line are .. A
786
B
1280
C
1920
D
2400
What is the approximate frequency limit of copper wire A
1 MHz
B
40 GHz
C 220
221
222
223
224
225
226
227
100KHz
D
10 GHz
Following circuit is used to generate PPM from PWM signal A
Astable multivibrator
B
D-Flip flop
C
Monostable multivibrator
D
Schmit trigger
What will be minimum storage requirement according to Nyquist theorem to store audio signal of 20Hz-15KHz with 8 bit quantization for the duration of 1 minute? A
1.2 MB
B
1.8 MB
C
30 KB
D
64 KB
Data rate of one speech channel in LPC-10 vocoder is ….. A
2.4 kbps
B
4 kbps
C
8 kbps
D
16 kbps
Total 12 telephone quality speech channels are time division multiplexed using DPCM technique. Total transmission rate will be….. A
128 kbps
B
192 kbps
C
256 kbps
D
384 kbps
Following hardware is used for pulse shaping … A
Low pass filter circuit
B
High pass filter circuit
C
Transversal filter
D
All of above
HDMI Cable used in modern LCD/LED TV provides … A
Digital Connection
B
Carries video signal
C
Carries audio signal
D
All of above
Equalizer is used to ….. A
Reshape incoming pulses
B
Boost high freq components
C
To boost low freq components
D
Amplify incoming pulses
Gaussian filter is used in GMSK technique to A
To achieve smooth phase transitions of carrier
B
To reduce bandwidth requirement for transmission.
C
To achieve zero ISI at decision making instant of neighboring
D
All of above
pulse 228
229
230
231
232
233
234
235
Following parameter is not coded in the LPC-10 vocoder A
Pitch
B
Gain
C
Sample value
D
Voice/Unvoiced determination
How many samples are there in 40 ms frame of telephone quality speech ? A
160
B
200
C
320
D
400
Following circuit is not used in detecting information from the PPM signal A
Low pass filter
B
Bistable multivibrator
C
Amplifier
D
Monostable multivibrator
If we increase number of quantization levels in PCM system….. A
We get good SNR
B
Large bandwidth required for transmission
C
More bits required to represent information
D
All of above
If we increase sampling rate in the PCM system .. A
Transmission bit rate will increase
B
Storage requirement will increase
C
No possibility of aliasing error
D
All of above
Following is not handshaking signal for RS232 serial communication A
RTS
B
Strobe
C
CTS
D
DTR
Mean quantization noise in PCM system if sine wave of peak to peak amplitude of 16 volt is quantized with 4 bits. A
0.0833
B
0.05
C
0.5
D
4
Adaptive delta modulation is used to A
Reduce transmission rate
B
Remove slope overload and threshold error
C
Dynamic sampling rate
D
All of above
236
237
238
239
240
241
242
243
Sigma-Delta modulation is used to A
Pre-emphasize low frequency content
B
Increase correlation between adjacent samples
C
Simplify receiver design
D
All of above
Following is not criteria for spread spectrum system….. A
Bandwidth of transmitted signal must be large enough
B
SNR should increase as bandwidth increase
C
Bandwidth expansion factor should be independent of message signal
D
None of above
Relation between channel capacity C and bandwidth B can be given by equation A
SNR = 7.78 + 20logC
B
C=2Blog10(1+SNR)
C
C=2Blog2(SNR)
D
C=Blog2(1+SNR)
Noise generator is electronic model of speech generation system represents… A
Vowels
B
Voiced sound
C
Unvoiced sound
D
Pitch
10 Speech channels are multiplexed using TDM then separation between two frame of speech will be …. A
12.5 µS
B
125 µS
C
1250 µS
D
None of above
Number of scanning lines and trace time per line in CCIR-B Television system used in India is … A
625 lines, 52 µS
B
525 lines, 53 µS
C
625 lines, 64 µS
D
525 lines,12 µS
One time slot of a TDMA frame in GSM standard contains ____ bits encrypted data A
156.25
B
114
C
57
D
26
One slot of TDMA frame in GSM standard contains total ___ bits A
156.25
B
114
C
57
D
26
244
245
246
247
248
249
250
Following database at MSC keeps information about identity of mobile phone equipment … A
HLR
B
VLR
C
EIR
D
AuC
Effects of fading is distributed to improve signal quality by technique .. A
Speech coding
B
Channel coding
C
Bit interleaving
D
Equalisation
Following type of technique suitable for bursty type traffic in form of packets A
PRMA
B
TDMA
C
FDMA
D
CDMA
Antenna gain in desired direction at cell site can be maximized by ______ A
Omnidirectional antenna
B
Parabolic antenna
C
Switched beam antenna
D
Dish antenna
To mitigate problem of ISI in TDMA system ________ technique is used A
Source encoding
B
Channel coding
C
Interleaving
D
Channel Equalisation
In M-ary coding system, signaling rate Rs=1/Ts and data rate Rb=1/Tb are related as: A
Ts=Tblog2M
B
Ts=TbxM
C
Ts=2Tblog10M
D
Rs=Rblog2M
Scrambling is done to achieve … A
To help synchronization
B
To make data pattern random
C
To remove long string of 1s and 0s
D
All of above
1
2
3
4
5
6
7
8
9
∇ x ∇ x E is A
∇∇. E - ∇2 E
B
∇2 E - ∇∇. E
C
∇2 E + ∇ E
D
∇. E - E .∇
Unit vector of E is A
E/E
B
E ( ax + ay + az )
C
E.E
D
E/E
E x H is A
EH cos θ
B
EH sin θ
C
EH sin θ an
D
EH cos θ an
E x ( A + C ) is A
ExC+ExA
B
E.A+ExC
C
A.E + C.E
D
AxE–ExC
Gradient of a scalar is A
Not defined
B
A vector
C
a scalar
D
Not periodic
Divergence of a vector is A
Not defined
B
a scalar
C
A vector
D
The same as gradient of a vector
The unit of del is A
Does not exist
B
meter
C
1/meter
D
dB
∇2 operates A
Only on scalar
B
Only on vector
C
On a scalar and also on a vector
D
Only on a constant
ax . ax is A
ax
B
1
C
0
D
ay
10
11
12
13
ax . ay A
0
B
1
C
az
D
-az
ax
X
1
B
0
C
az
D
-az
ax
X
0
B
1
C
az
D
ay
For static fields
C
17
18
∇xH=D ∇xH=0
B D
∇xH=J ∇xH=E
In free space A
16
ax is
A
C
15
ay is
A
A
14
is
∇xE=0 ∇.D = ρ v
B D
∇xE=ρ ∇ x E = - ∂B/∂t ∂t v
Unit of E is A
Volt
B
Amp/m
C
Volt/m
D
Volt/coulomb
Unit of H is A
Weber
B
ampere
C
Volt/m
D
Amp/m
Unit of D is A
Wb/m
B
Amp/m
C
C/m2
D
C/m
A
εE
B
εH
C
µH
D
ε ∂E/∂t ∂t
D is
19
20
21
22
23
24
∇.∂D/∂t ∂D ∂t is A
ρs
B
ρv
C
ρl
D
0
A
∂B/∂t ∂B ∂t
B
-∂B/∂t ∂B ∂t
C
∂D/∂t ∂D ∂t + J
D
J
∇ x E is The electric flux density , D is A
εE
B
εE
C
E / ε0
D
µE
The electric flux is A
Q
B
εD
C
εE
D
εQ
The unit of electric flux is A
Weber
B
Gauss
C
Tesla
D
Coulomb
In free space A C
25
C
27
B D
v
∇xE=0 ∇.E = ρ / ε v
0
In free space A
26
∇. E = 0 ∇.E = ρ
∇. B = 0 ∇xB=µ H 0
B D
∇. B = µ H ∇. B = H / µ 0
0
For free space A
σ=0
B
J = 1 Amp/m2
C
µr = µ0
D
εr = ε0
The unit of conduction current density is A
Amp/m
B
Amp/m2
C
Amp/m3
D
Amp
28
29
The unit of displacement current density is A
Amp/m2
B
Amp/m
C
Amp
D
Amp-m
B
Amp/m
D
Amp-m
The unit of conduction current is A C
30
31
32
33
34
35
Amp 2
Amp/m
The unit of permittivity is A
Farad
B
Henry
C
Farad/m
D
Henry/m
The unit of permeability is A
Henry/m
B
Farad/m
C
Henry
D
Weber
The conduction current density is A
σE
B
σD
C
E/ σ
D
εD
The displacement current density is A
ε ∂E/∂t ∂t
B
D
C
εD
D
ε0 E
For uniform plane wave propagation in z-direction A
Ez = 0
B
Ez ≠ f(y)
C
Ez ≠ f(x)
D
Ez = 0 , Hz = 0
The line integral of E around a closed loop is A
Zero
B
Q
C
Equal to current
D
ρv
36
37
38
39
40
41
The unit of attenuation is A
dB/m
B
V/m
C
Amp/m
D
Coloumb/m
Velocity of a plane wave whose εr = 4 , µr = 1 is A
3 x 108 m/s
B
1.5 x 108 cm/s
C
6 x 108 cm/s
D
2 x 108 cm/s
Velocity of uniform plane wave in free space is A
3 x 108 m/s
B
3 x 108 cm/s
C
3 x 106 cm/s
D
3 x 1010 cm/s
The unit of depth of penetration is A
dB
B
Meter
C
Neper
D
radian
E.H for a plane wave is A
Zero
B
1
C
Does not exist
D
EH
Equation of continuity is A C
42
43
44
∇.J = -∂ρ /∂t ∂t ∇.J = ∂ρ /∂t ∂t v
v
B D
∇.J = -ρ ∇.J = ∂ρ v
s
/∂t ∂t
Magnetic current density is given by A
B
B
∂D/∂t ∂D ∂t
C
∂B/∂t ∂B ∂t
D
-∂B/∂t ∂B ∂t
The unit of magnetic current density is A
Amp/m2
B
Volt/m2
C
Amp
D
Amp/m
Boundary conditions on E is A
an X (E1 – E2 ) = 0
B
Et1 = Et2
C
an . (E1 – E2 ) = 0
D
an . E1 = 0
45
46
47
48
49
Boundary conditions on H is A
Ht1 = Ht2
B
Ht1 - Ht2 = Js
C
an X (H1 – H2 ) = Js
D
an X (H1 – H2 ) = 0
Boundary conditions on B is A
an X (B1 – B2 ) = 0
B
an . (B1 – B2 ) = 0
C
an . (H1 – H2 ) = Js
D
Bn1 = Bn2
Boundary conditions on D is A
an . (D1 – D2 ) = 0
B
an . (D1 – D2 ) = ρs
C
an X (D1 – D2 ) = ρs
D
an X (D1 – D2 ) = 0
Boundary conditions on J is A
an X (J1 – J2 ) = 0
B
an . (J1 – J2 ) = 0
C
an X (J1 – J2 ) = Js
D
an . (J1 – J2 ) = Js
Lorentz Gauge condition is A C
50
51
52
53
∇.A = - µ ε ∂V /∂t ∂t ∇x A = B
B D
∇x A = H ∇.A = - ∇∂V /∂t ∂t
Equation of continuity is A
J.dS = I
B
J.dS = Q
C
J.dS = J
D
J.dS = ρv
Intrinsic impedance of a medium is given by A
Sqrt(µ / ε )
B
Sqrt( jωµ / (σ + jωε )
C
Sqrt(ε /µ )
D
Sqrt(µ ε )
The characteristic impedance of free space is A
277 Ω
B
120 Ω
C
377 Ω
D
120π2 Ω
The wave equation in free space is A
∇2 E = µ0 ε0 ∂E /∂t ∂t
B
∇2 E = µ0 ε0 ∂2E /∂t ∂t
C
∇2 V = - ρv / ε
D
∇2 E = µ σ ∂2E /∂t ∂t
54
55
56
57
58
59
60
61
E and H are always perpendicular to each other A
Yes
B
Some times
C
Only for uniform plane wave
D
None of these
Velocity of propagation of a plane wave is A
β/ω
B
ω/β
C
λ/f
D
f /λ
Attenuation of plane wave in free space is A
Zero
B
infinite
C
Propagation constant
D
β itself
A medium is a good conductor if A
(σ / ω ε ) >> 1
B
(σ / ω ε) << 1
C
(σ / ω ε ) = 1
D
(σ / ω ε ) = 0
A medium is a good dielectric if A
(σ / ω ε ) >> 1
B
(σ / ω ε) << 1
C
(σ / ω ε ) = 0
D
(σ / ω ε ) = 1
The ratio of conduction current to displacement current is A
σ/ωε
B
ωε /σ
C
0
D
1
Dissipation factor of a dielectric is A
σ/ωε
B
ωε /σ
C
1
D
0
B
Inversely proportional to square root of conductivity
D
Directly proportional to conductivity
B
Inversely proportional to conductivity
depth of penetration in good conductors is A C
62
Inversely proportional to conductivity Not a function of conductivity
Attenuation constant in good dielectrics is A
Directly proportional to conductivity
C 63
64
65
66
67
68
69
70
Inversely proportional to square root of conductivity
D
Not a function of conductivity
Phase velocityof uniform plane wave is A
Directly proportional to ε
B
C
Not a function of ε
D
Inversely proportional to ε Not Inversely proportional to square root of ε
Phase constant of a uniform plane wave in a medium is A
Directly proportional to frequency
B
C
Is inversely proportional to frequency
D
Not a function of frequency Is inversely proportional to square root of frequency
The characteristic impedance of a medium is A
Sqrt(µ / ε )
B
Is a function of frequency
C
Not a function of frequency
D
Is independent of µ , ε and f
Poynting vector gives A
Instantaneous power density
B
Average power density
C
Total power
D
Total power density
Standing waves are produced when A
There are no reflections
B
There are full reflections
C
There is only transmission
D
The waves are incident on good dielectrics
The minimum value of voltage standing wave ratio is A
0
B
-1
C
1
D
-∞
When the load impedance ZL = Z0 , the VSWR is A
10
B
1
C
0
D
∞
Brewster angle is A
Angle of incidence for which there is no reflection
B
Angle of refraction for which there is no reflection
C
Equal to reflected angle
D
Equal to refraction angle
71
72
73
74
75
76
77
78
79
The range of HF is A
3-30 kHz
B
30-300 kHz
C
3-30 MHz
D
30-300 MHz
The range of VHF is A
3-30 MHz
B
30-300 MHz
C
300 MHz-3 GHz
D
300 kHz – 300 MHz
The standard antenna for reference is A
Isotropic antenna
B
Half-wave dipole
C
Dish antenna
D
Yagi Uda antenna
The most common popular prevalent TV antenna is A
Dipole
B
Monopole
C
dish
D
horn
Among the following the Broadband antenna is A
Log-periodic
B
dipole
C
Yagi-Uda
D
Horn
Among the following the non-resonant antenna is A
dipole
B
Yagi-Uda
C
Monopole
D
rhombic
The common microwave link antenna is A
dipole
B
Log-periodic
C
Rhombic
D
Parabolic dish
Antenna for direction finding is A
Yagi-Uda
B
Rhombic
C
Parabolic dish
D
Loop
The directivity of half-wave dipole is
80
81
82
83
84
85
86
87
88
A
10
B
1
C
1.5
D
1.64
The directivity of current element is A
1.64
B
1.5
C
2.0
D
5.0
Reflectors in Yagi-Uda antenna are A
1
B
More than 1
C
3
D
10
Directors in Yagi-Uda antenna are A
More than 1
B
1
C
5
D
3
Radar antenna is A
Parabolic dish
B
dipole
C
Horn
D
waveguide
The length of the folded dipole in yagi – uda antenna is A
468/f (MHz) feet
B
492/ f (MHz) feet
C
342/f (MHz) feet
D
192/f (MHz) feet
The impedance of folded dipole in yagi-uda antenna is A
Inductive reactance
B
Capacitive reactance
C
Purely resistive
D
73 Ω
The radiation resistance of a current element is A
80 π2 ( dl / λ )2 Ω
B
80 π ( dl / λ )2 Ω
C
80 π2 ( dl / λ ) Ω
D
80 π ( dl / λ ) Ω
Circularly polarized antenna is A
Dipole
B
Parabolic dish
C
Yagi-uda
D
helical
If the current element is y-directed , the resultant vector magnetic potential is
89
A
y-directed
B
x-directed
C
z-directed
D
θ-directed
For time-varying fields
∇V
A
E=-
B
E = -∇ V - ∂A /∂t ∂t
C
E = -∇ V - ∂D /∂t ∂t
D
E = -∇ V - ∂H /∂t ∂t
100 poynting vector gives A
Direction of electric field
B
Polarization of electromagnetic wave
C
Power flow
D
Rate of energy flow
101 The length of folded dipole in yagi-uda antenna is A
Frequency dependent
B
Frequency independent
C
Equal to λ
D
Equal to 0.2 λ
102 The spacing between folded dipole and reflector is A C
λ > λ /2
B
λ /2
D
< λ /2
103 Voltage standing wave ratio is A
Vmin / Vmax
B
Vmax / Vmin
C
Vreflected / Vincident
D
Vmax
104 Antenna is a A
transducer
B
filter
C
Regulator
D
amplifier
105 The radiation resistance of a half wave dipole close to earth is A
73 Ω
B
< 73 Ω
C
> 73 Ω
D
Infinity
106 If the directivity is high , the beam width is A
High
B
low
C
constant
D
Very high
107 Director in yagi-uda antenna is A
Active element
B
Driven element
C
Parasitic element
D
Identical to dipole
108 Reflector in yagi-uda antenna is A
Active element
B
Driven element
C
Identical to dipole
D
Parasitic element
109 Log-periodic antenna is A
Narrow band
B
Wide band
C
Frequency independent
D
Frequency dependent
110 In vertical dipole , the electric field is A
Parallel to the dipole
B
Perpendicular to dipole
C
Θ- directed
D
circular
111 The effective length of a vertical radiator is A
Increased by capacitive hat
B
Increased by loading with lumped Inductance
C
Increased by supplying more power
D
Increased by resistance loading
112 The null-to-null beam width in end-fire array is A
2λ/Nd
B
Sqrt(2 λ / N d )
C
2 sqrt(λ / N d )
D
2 sqrt(2 λ / N d )
113 The null-to-null beam width in broad side array is A
2λ/Nd
B
2 sqrt(2 λ / N d )
C
2 λ2 / N d
D
Sqrt(N d / 2 λ )
λ
114 The length of resonant dipole is A
λ /2
B
C
λ /4
D
115 The first side lobe level in uniform array is
2λ
A
0.212
B
0.121
C
0.312
D
0.51
116 The side lobe level in binomial array is A
Zero
B
-13.5 dB
C
-20 dB
D
Zero dB
117 In binomial array the central elements are excited A
strongly
B
Weakly
C
Uniformly
D
easily
118 In horizontal polarized waves the electric field is A
Parallel to the ground
B
Perpendicular to the ground
C
In Θ-direction
D
Elliptical
119 The maximum directive gain of current element is A
1.76 dB
B
2.15 dB
C
3 dB
D
0 dB
120 Band width of an antenna is A
f0 / Q
B
Q / f0
C
f0 Q
D
f0 / Q
2
121 Antenna can be used as A
Sound sensor
B
Light sensor
C
Temperature sensor
D
Colour sensor
122 For far field of z-directed current element A
Hφ = - sin θ ∂Az/∂r ∂r
B
Hφ = 0
C
Hφ = H θ
D
Hφ = Hr
123 Induction and far fields have equal magnitudes at
A
r = λ/ 2 π
B
r = λ/ 6 π
C
r = λ/ π
D
r=∞
124 Induction and radiation fields have equal magnitudes at A
r = v0 / ω
B
r = v0 / 2 π
C
r = v0 / β
D
r = v0 / λ
125 If the output signal power level is 1 W , power gain is A
0 dB
B
1 dB
C
10 dB
D
∞ dB
126 LF antennas are usually used for A
Vertical polarization
B
horizontal polarization
C
Circular polarization
D
Elliptical polarization
127 The real part of antenna impedance consists of A
Rr only
B
Rr and Rl
C
Rl only
D
Zero ohms of resistance
128 Power and field patterns are related as A
P ∝ E2
B
P∝E
C
P ∝ √E
D
P
∝ 1/ E
129 For radiation pattern measurement the distance of the far field region is A
r > 2 D2 / λ
B
r < D2 / λ
C
r= λ/π
D
r= D/π
130 GTEM cell means A
Geometric transverse electromagnetic cell
B
Giga Hertz TEM cell
C
Grounded TEM cell
D
Geo TEM cell
131 Whetastone bridge is used to measure antenna impedance at a frequency of A
Giga hertz
B
Upto microwave frequency range
C
Upto millimeter range
D
Upto 30 MHz
132
2
If the field measurements are made at r < 2 D / λ A
Side lobe levels will be high
B
Bandwidth will be small
C
Band width and side lobe levels are small
D
No side lobes appear
133 Null-to –Null bandwith is A
Equal to 3 dB bandwith
B
Greater than 3 dB band width
C
less than 3 dB band width
D
Not related to 3 dB band width
134 Antenna efficiency is A
gp / gd
B
gd / gp
C
gp
D
gd
B
ω/β
135 Phase difference is A
β
D β/ω Path difference x β 136 If the response of a vertical dipole is 1 for a unity normalized input power , the polarization is C
A
Vertical
B
Horizontal
C
Circular
D
elliptical
137 If the response of RCP helix is zero , the polarization of test antenna is A
LCP
B
RCP
C
Horizontal
D
Vertical
138 If the response of RCP helix is maximum , the polarization of test antenna is A
LCP
B
RCP
C
Horizontal
D
Vertical
139 If the response of LCP helix is maximum , the polarization of test antenna is A
LCP
B
RCP
C
Horizontal
D
Vertical
140 If the response of a horizontal dipole is maximum , the polarization of test antenna is A
Horizontal
B
Vertical
C
Circular
D
elliptical
141 If the response of any type of antenna is 0.5 for unity normalized power, the polarization of test antenna is A
Linear
B
Horizontal
C
Vertical
D
unpolarised
142 The excitation levels of a three element binomial array are A
1,2,1
B
1,3,1
C
1,4,1
D
2,3,2
143 The excitation levels of a four element binomial array are A
1,3,1,1
B
1,2,2,1
C
1,3,3,1
D
1,4,4,1
144 The basic transmission loss between transmitter and receiver is A
10 log ( ( 4 π d )/λ )2
B
10 log (λ / ( 4 π d ))2
C
10 log ( GTX GRX )
D
zero
145 Actual transmission loss between transmitter and receiver is A C
10 log { (λ / ( 4 π d ))2 * 1/ ( GT GR ) } 10 log { ( ( 4 π d )/λ ) * GT GR }
B
10 log { ( ( 4 π d )/λ )2 * 1/ ( GT GR ) }
D
10 log { (λ / ( 4 π d )) * ( GT GR ) }
146 Friss formula is A
La = (λ / ( 4 π d ))2
B
La = ( ( 4 π d )/λ )2
C
La = 10log10( ( 4 π d )/λ )2 * 1/ ( GT GR )
D
La = 10log10( ( 4 π d )/λ )2
147 Noise figure of antenna is A
Te / T0
B
1 + (Te / T0 )
C
1 - (Te / T0 )
D
1 + (Te / T0 )2
148 Actual transmission loss in dB between transmitter and receiver is A
Greater than basic transmission loss
B
C
Equal to basic transmission loss
D
less than basic transmission loss infinite
149 Schelkunoff polynomial method gives A
Nulls in the desired direction
B
Nulls in undesired directions
C
Desired side lobes
D
Desired beam width
150 Range of VSWR is A
0 to 1
B
1 to ∞
C
0 to ∞
D
-∞ to ∞
151 Tchebyscheff polynomial method gives A
Desired side lobe ratio
B
Desired beam width
C
Desired overall pattern
D
Desired phase function
152 The advantage of uniform linear array is A
The required number of sources is one
B
SLR is small
C
Number of side lobes are less
D
Grating lobes are present
153 The current distribution in half-wave dipole is A
Sinusoidal
B
constant
C
Triangular
D
parabolic
154 When the array length high, the null –to-null beam width is A
Small
B
High
C
Constant
D
infinity
155 Conducting properties of earth are A
Constant with frequency
B
Change with frequency
C
Change with the type of antenna
D
Change with excitation of antenna
156 In conductor , if charge is not moving , the radiation is A
Very high
B
Zero
C
The same as when charge moves
D
moderate
157 If a charge is moving with a uniform velocity in an infinite straight wire , the radiaton is A
Infinite
B
Moderate
C
Zero
D
high
158 If the charge is moving in a curved wire , radiation A
Exists
B
Does not exist
C
Is infinite
D
Same as when the wire is straight
159 If the charge oscillates with time in a straight wire , it A
Radiates
B
Does not radiate
C
Stores energy
D
oscillates
160 If the charge accelerates , there exists A
No radiation
B
Radiation
C
Stored energy
D
Acceleration of antenna
161 If the charge deccelerates , radiation A
Is zero
B
Exists
C
Does not exist in any antenna
D
Exists only in some wire antenna
162 The primary equation for electromagnetic radiation in a very thin z-directed wire of length L A
L dIz / dt = L ρL az
B
L dIz / dt = L ρL ay
C
L dIz / dt = ρL ay
D
L dIz / dt = L ρL
163 Radiation with broad frequency spectrum is very strong if A
pulses are of shorter duration
B
pulses are of longer duration
C
Pulses have more amplitude
D
Pulses have small amplitude
164 For frequency independent antennas , the band width is A
zero
B
∞
C
Finite
D
Moderate
165 The radiation intensity of an isotropic radiator is A
Pr / 4 π r2
B
Pr / 4 π r
C
Pr / 4 π
D
Pr
166 An omni directional antenna from the following A
Parabolic dish
B
Dipole
C
Horn
D
Yagi-uda antenna
167 Loop antenna is a A
Isotropic radiator
B
Directional radiator
C
Omni-directional radiator
D
Point source
168 Broad side arrays are A
Omni-directional
B
Point sources
C
Directional antennas
D
Isotropic antennas
B
Only one component
169 In linear polarization , there exists A C
Three components Two components differing by 900
phase
D
Two components differing by 2700
phase
170 If there exists two orthogonal linear components which are in time phase, polarization is A
Linear
B
Circular
C
Elliptical
D
Not present
171 Effective area of an antenna is A
Ratio of power delivered to load to power density of incident wave
B
Ratio of radiation intensity to power density of incident wave
C
gp / gd
D
gd / gp
172 Aperture efficiency , η of an antenna is a A
The ratio of gp and gd
B
Maximum effective area to physical area
C
Effective area to physical area
D
Physical area to effective area
173 In far-field region , the angular field distribution is independent of A
Transmitter power
B
Distance from the antenna
C
Angular region
D
Antenna type
174 Fresnel region is A
Far-field region
B
Near-field region
C
The region of constant field
D
The region of no field
175 Fraunhofer region is A
Far-field region
B
Near-field region
C
The region of constant field
D
The region of no field
176 Reactive near-field region exists when A
R > 0.62 * sqrt( D3 /λ )
B
R < 0.62 * sqrt( D2 /λ )
C
R < 0.62 * sqrt( D3 /λ )
D
R > 0.62 * sqrt( D2 /λ ) R ≥ 0.62 * sqrt( D3 /λ ) and R < 2D2 /λ
177 Fresnel region exists when A
R ≤ 0.62 * sqrt( D /λ )
B
C
R ≥ 2D2 /λ
D
R ≥ 0.62 * sqrt( D3 /λ )
3
178 Fraunhofer region exists when A
R > 2D2 /λ
B
R < 2D2 /λ
C
R ≥ 0.62 * sqrt( D3 /λ )
D
R ≤ 0.62 * sqrt( D3 /λ )
179 Unit of directivity is A
Watts
B
Watts/m2
C
Watts/m3
D
nil
180 Unit of solid angle A
Degrees
B
Radian
C
Sterradian
D
nil
181 If h is the height of an antenna , the number of side lobes are A
h/ λ
B
2 h/ λ
C
4
D
2λ/h
182 Divergence factor of a field from earth is
Reflected field from flat earth / Reflected field from curved B surface / reflected field from flat reflected field from curved surface surface Reflected field from curved earth incident field from curved earth C / incident field from curved D / reflected field from curved surface surface 183 If Rr is radiation resistance , µe is effective permeability of ferrite core , the radiation resistance of ferrite loop is A
A
Rr (µ0 / µe )2
B
Rr (µe / µ0 )2
C
Rr
D
Rr µ0
184 The resultant field of an array antenna is
185
A
The product of element pattern and array factor
B
Array factor
C
Sum of element patterns
D
Element pattern
The excitation required to orient a beam in θ0 direction is A
kd cos θ0
B
-kd cos θ0
C
-kd
D
kd
186 Super directivity of an array can be obtained by A
Reducing the spacing
B
Increasing the spacing
C
Reducing the number of elements
D
Decreasing array length
187 Super directivity obtained by reducing the spacing and increasing the number of elements results in A
High reactive power and Q
B
C
Small Q
D
low reactive power and Q High reactive power and lower Q
188 Circular antennas are most sensitive to A
Linearily polarized waves
B
Elliptically polarized waves
C
Circularly polarized waves
D
Unpolarised waves
λ
189 Circular antenna has usually a length of A
λ/2
B
C
2λ
D
λ/4
190 The horizontal pattern of a circular antenna is
191
A
Circle
B
Four equal lobe pattern
C
Figure-eight pattern
D
Six equal lobe pattern
Two end fire circular antenna elements with 90 º phasing produce A
Unidirectional pattern
B
Figure eight pattern
C
Multidirectional pattern
D
No radiation pattern
192 Cirular antennas are widely used at A
VLF
B
HF
C
Microwave frequency
D
UHF
193 Directors in yagi uda antenna A
Reduces the characteristic impedance of a driven antenna element
B
increases the characteristic impedance of a driven antenna element
C
Has no effect on the characteristic impedance of driven element
D
Act as open circuit
194 Directors and reflectors are used to A
Reduce the impedance
B
increase the impedance
C
Increase the gain
D
Form an array
195 Due to use of parasitic elements the bandwidth of yagi-uda antenna is A
Increased
B
Not affected
C
Made ideal
D
Limited
196 Yagi-uda antenna has A
Poor front to back ratio
B
good front to back ratio
C
infinite front to back ratio
D
zero front to back ratio
197 V-antenna yields A
Bidirectional pattern
B
Unidirectional pattern
C
Good signal strength compared to dipole
D
Less band width compared to dipole
198 V-antenna is popular for A
Satellite reception
B
FM reception
C
Mobile reception
D
Radar signal reception
199 If the power gain of an antenna is 0.5 dB , the power ratio is A
0.216
B
12.6
C
1.26
D
1.06
200 If the voltage gain of an antenna is 1.0 dB , the voltage ratio is A
1.26
B
0.126
C
1.06
D
1.0
201 If the power gain of an antenna is 30 dB , the power ratio is A
1.477
B
1000
C
100
D
10
202 If the power gain of an antenna is 20 , the power gain in dB is A
13
B
130
C
20
D
200
203 If a dipole is tilted forward , the band width becomes A
Zero
B
Infinite
C
More
D
reduced
204 If a 300 Ω line is terminated in 75 Ω dipole , SWR is A
4
B
0.25
C
8
D
2
205 The power density at a distance of 1 km from 1 kW isotropic radiator is A
795 mW / m2
B
79.5 mW / m2
C
795 µW / m2
D
79.5 µW / m2
206 For radio wave propagation , fresh water is considered to be A
Very poor
B
Poor
C
Very good
D
average
207 For radio wave propagation , cities are considered to be A
Poor
B
Very poor
C
Very good
D
good
208 The phase velocity of a wave in medium whose ε = 0 is r A
∞
B
0
C
Finite
D
V0
209 Antenna radiation efficiency is high when its length is A
λ/ 2
B
λ
C
3 λ/ 2
D
∞
210 Antenna resonates when its length is integer multiples of A
λ
B
λ/ 2
C
λ/ 4
D
λ/ 3
211 For a 100 Ω antenna with 2 A of current , radiated power is A
400 watts
B
200 watts
C
50 watts
D
25 watts
212 For a perfect conductor the power transmission coefficient is
213
A
1
B
zero
C
∞
D
Reflection coeeficient
For a perfect conductor , the power transmission coefficient |ρ|2 is A
Equal to transmission coefficient
B
1–T
C
1
D
0
214 The Rayleigh criterion in the case of reflection of electromagnetic wave from semirough surface is A
Cos θi > λ/ 8d
B
Cos θi = λ/ 8d
C
Cos θi < λ/ 8d
D
Cos θi = 0
215 The percent bandwidth of an antenna with an optimum frequency of operation of 500 MHz and - 3 dB frequencies of 300 MHz and 350 MHz is A
20 %
B
100 %
C
500 %
D
10 %
216 The received power of a receiving antenna whose effective area is 0.2 m2 for an
available power density of 100 µ W / m2 A
200
B
20
C
50
D
500
217 For an ideal antenna , the directivity is A
Power gain
B
1
C
1.64
D
1.5
218 For an ideal antenna , the radiation resistance is A
73 Ω
B
36.5 Ω
C
293 Ω
D
Input impedance
219 The power gain in dB of isotropic radiator is A
0
B
1
C
1.5
D
1.64
220 The normalized power of a dipole is A
1
B
1.5
C
Sin2 θ
D
1.64
221 If the resistance part of antenna is 100 Ω , radiation resistance is 80 Ω , the antenna efficiency is A
0.8
B
10/8
C
0.4
D
8/18
222 If Φ is the angle between the axis of a receiving dipole and the direction of electric field , the polarization loss factor is A
Sin Φ
B
cos Φ
C
tan Φ
D
sec Φ
223 The effective length of a half wave dipole is A
0.4 λ
B
0.45 λ
C
λ/π
D
0.55 λ
225 Effective area of a Hertzian dipole is A
0.2 λ2
B
0.25 λ2
C
0.119 λ2
D
0.3 λ2
226 Directive gain is equal to power gain if A
η=∞
B
η=1
C
η = gp
D
η = gd
227 Directive gain and directivity are equal for
228
A
Directional antenna
B
Dipole
C
Parabolic dish
D
Isotropic antenna
For an isotropic antenna operating at λ = sqrt(4 π ) , the effective area is A
4π
B
1
C
(4 π )2
D
2
229 Directivity is inversely proportional to square of beam width Directly proportional to square of C Directly proportional to beam width D beam width 230 If the direction of propagation of an electromagnetic wave is in z-direction , the polarization is in A
inversely proportional to beam width
B
A
z-direction
B
y-direction
C
x-direction
D
Circular polarization
231 If the quality factor of an antenna is 1000 , resonant frequency is 10 MHz its band width is A
100 kHz
B
10 kHz
C
10 Hz
D
10 MHz
232 The maximum effective area of an antenna operating at λ = 10 cm with the directivity of 100 is A
1000 cm2
B
(1/4 π ) m2
C
4 π m2
D
10 π m2
233 The radiation resistance of an antenna which radiates 10 kW when a current of 10 ampere flows in it , is A
100 Ω
B
1,000 Ω
C
10 Ω
D
100 kΩ
234 When an antenna radiates 10 kW in forward and 1 kW in backward directions , the front-to-back ratio of an antenna is A
1 dB
B
10 dB
C
100 dB
D
0 dB
235 If a medium has ε = 81 , σ = 2 mho/m , f = 10 GHz , it is r A
A conductor
B
A bad conductor
C
An insulator
D
A good insulator
236 The radiated electric field is A
α dl
B
α (dl)2
C
α 1/ dl
D
α 1/(dl)2
237 Poynting vector has the unit of A
Watts / m3
B
watts
C
Watts / m2
D
Volt-ampere
238 The current element has a directive gain of A
3/2
B
2/3
C
1
D
1.64
239 The polarization of horizontal dipole is A
Vertical
B
Horizontal
C
Θ - polarization
D
elliptical
240 To receive horizontally polarized wave , the receiving antenna should be polarised A
Vertically
B
Horizontally
C
Circularly
D
Elliptically
241 The skin depth of an ideal conductor is A
∞
B
Zero
C
Finite
D
Sqrt(ωµσ )
242 The conducting properties of a medium depends on A
σ Only
B
ε only
C
f only
D
σ , ε and f
243 The surface current density of a good dielectric medium is A
Zero
B
Infinity
C
Finite
D
-1
244 The surface charge density of a good dielectric medium is
245
A
-1
B
Infinity
C
Finite
D
Zero
In the boundary condition Dn1 - Dn2 = ρs , the unit of ρs is A
C / m3
B
C / m2
C
C/m
D
C
246 In the boundary condition H – H = J , the unit of J t1 t2 s s A
Ampere
B
Amp/m
C
Amp/m2
D
H/m
247 In the boundary condition B - B = 0 , the unit of B is n1 n2 n1 A
Wb
B
Wb/m
C
Tesla/m
D
Wb/m2
248 In the boundary condition E – E = 0 , the unit of E is t1 t2 t2 A
Volt/m2
B
Volt/m
C
Volt
D
Volt-m
A
∇xE
B
B/µ
C
∇.B
D
P/E
249 H is
250 The permittivity of a space is A
1
B
ε0
C
>1
D
∞
251 The electric field of a circularly polarized wave is represented by A
( ax + j ay ) e j ( ω t
C
ax e j ( ω t
-βz)
-βz)
B
( ax + j ay ) e j ( ω t )
D
ay e j ( ω t
-βz)
252 A qurter wave line yields A
Zero impedance
B
Infinite impedance
C
Impedance inversion
D
Real and reactive impedance
253 The tangential electric field at a perfect conductor is A
1
B
∞
C
Zero
D
-∞
254 An electromagnetic wave when incident on a perfect conductor is A
Reflected completely
B
Transmitted completely
C
Reflected and transmitted
D
Refracted completely
255 The electric field of elliptically polarized electromagnetic wave is represented by A
( ax + j ay ) e j ( ω t
C
Ex a x e j ( ω t
-βz)
-βz)
B
( Ex ax + j Eyay ) e j ( ω t
D
Eyay e j ( ω t
-βz)
256 The transmission line can be converted into A
A dipole antenna
B
A dish antenna
C
A horn
D
lens
257 The length of the mobile antenna is a A
λ
B
λ /2
C
λ/4
D
>λ
258 E.H of uniform plane wave is A
EH
B
0
C
η E2
D
None of these
259 For static magnetic field A
∇XB=ρ
B
∇XB=µJ
C
∇ . B = µ0 J
D
∇XB=0
-βz)
260 Electric field in free space A
D / ε0
B
D / µ0
C
ε0 D
D
σ/ ε0
261 For uniform plane wave in x-direction A
Ex = 0
B
Hx = 0
C
Ex = 0 and Hx = 0
D
None of these
262 Displacement current density is A
D
B
J
C
∂D/∂t
D
∂J/∂t
263 Depth of penetration in free space is A
α
B
1/ α
C
0
D
None of these
264 Complex pointing vector P is A
P= - E x H*
B
P= E x H*
C
P= ½ E x H*
D
None of these
265 The time varying field is A
E=-∇V
B
E = - ∇ V -∂A/∂t
C
E = - ∇ V -B
D
E=-∇V-D
266 Uniform plane wave is A
Longitudinal in nature
B
Transverse in nature
C
Neither transverse nor longitudinal
D
Vertically directed
267 The direction of propagation of EM wave is obtained from A
ExH
B
E.H
C
E
D
H
268 An electromagnetic field can exist if it satisfies A
Gauss’s law
B
Faraday’s law
C
Coulomb’s law
D
All Maxwell’s equations
269 If σ = 2.0 mho/m , E=10.0 V/m , the conduction current density is A
5.0 A/m2
B
20.0 A/m2
C
40.0 A/m2
D
20 A
270 Maxwell’s equations give the relations between A
Different fields
B
Different Sources
C
Different boundary conditions
D
None of these
271 The velocity of EM wave is A
Inversely proportional to β
B
Inversely proportional to α
C
Directly proportional to β
D
Directly proportional to α
272 Velocity of a wave in a good conductor is A
Very small
B
Very large
C
Moderate
D
None of these
273 If E = 2 V/m , of a wave in free space , (H) is
274
275
A
1 / 60 π A/m
B
60 π A/m
C
120 π A/m
D
240 π A/m
If wet soil has σ = 10-2 1 /m , εr =15 , µr = 1 , f = 60 Hz , it is a A
Good conductor
B
Good dielectric
C
Semi conductor
D
None of these
If wet soil has σ = 10-2 1 /m , εr =15 , µr = 1 , f = 10 GHz , it is a A
Good conductor
B
Good dielectric
C
Semi conductor
D
Semi dielectric
276 The cosine of the angle between two vectors is A C
Sum of products of the directions of the two vectors Product of products of the directions of the two vectors
B
Difference of products of the directions of the two vectors
D
None of these
277 The electric field intensity E at appoint (1,2,2) due to (1/9) nc located at (0,0,0) is A
33 v/m
B
0.333 V/m
C 278
279
0.33 V/m
D
Zero
If E is a vector , then ∇ . ∇ x E is A
0
B
1
C
Does not exist
D
None of these
The Maxwell’s equation ∇.B = 0 is due to A
B=µH
B
B=H/µ
C
Non existence of a monopole
D
None of these
280 Velocity of EM wave in free space is A
Independent of f
B
Increases with increase in f
C
Decreases with increase in f
D
None of these
281 The direction of propagation of EM wave is given by A
The direction of E
B
The direction of H
C
The direction of E x H
D
The direction of E.H
282 For uniform plane wave propagating in z-direction A
Ex = 0
B
Hx = 0
C
H y = 0 , Ey = 0
D
Hz = 0 , Ez = 0
283 For free space A
σ=∞
B
σ=0
C
J≠0
D
None of these
284 Velocity of propagation of EM wave is A
Sqrt(ε0 / µ0 )
B
µ0 / ε0
C
1/sqrt(µ0 ε0 )
D
ε0 / µ0
285 Electric field for time varying potentials A
E=-∇V
B
E=-∇V-A
C
E= ∇V
D
E=-∇V+A
286 The intrinsic impedance of a medium whose σ = 0 , ε = 9 , µ = 1 Is r r A
40π Ω
B
9Ω
C
120π Ω
D
60π Ω
287 For time varying EM fields A
∇xH =J
B
∇ x H = ∂D/∂t + J
C
∇xE =0
D
None of these
288 The wave length of a wave with a propagation constant = 0.1 π + j 0.2 π A
10 m
B
20 m
C
30 m
D
25 m
289 The electric field just above a conductor is always A
Normal to surface
B
Tangential to source
C
Zero
D
∞
290 The normal components of D are A
Continuous across a dielectric boundary
B
Discontinuous across a dielectric boundary
C
Zero
D
∞
291 An antenna is a synonyms to a A
Generator
B
Transformer
C
Regulator
D
Reflector
292 A unipole is also known as A
Omnidirectional radiator
B
Unidirectional director
C
Line radiator
D
None of the above
292 The directive gain of an antenna is given by A
Radiation intensity in a particular direction / maximum radiated power
B
Average radiated power/maximum radiated power
C
Radiation intensity in a particular direction / average radiated power
D
Average radiated power / radiation intensity in a particular direction
293 The numeric value of directive gain may lie between A
- 1 And + 1
B
0 and 1
C
0 and ∞
D
1 and ∞
294 Which of the following constitute the loss resistance of an antenna ? A
Dielectric loss
B
Leakage loss in insulation
C
Loss in earth connection
D
All of the above
295 In case of antenna the ratio of the power radiated in desired direction to the power radiated in the opposite direction is known as A
Transmission efficiency
B
Front to back ratio
C
Loss coefficient
D
None of the above
296 Front-to-back ratio can be increased by A
Sacrificing gain
B
Increasing the size of conductor
C
Using the materials of high conductivity
D
All of the above
297 A half wave dipole used at a frequency of 300 MHz has a length of A
10 m
B
3m
C
1m
D
50 cm
298 A vertical earthed antenna is resonant when its physical height is equal to A
λ
B
λ/2
C
λ/4
D
λ/8
299 A folded dipole antenna is conveniently connected to A
Shielded line
B
Two wire line
C
Coaxial line
D
Flat ribbon type transmission line
300 The bandwidth of an antenna is A
Directly proportional to Q
B
Inversely proportional to Q
C
Directly proportional to Q2
D
Inversely proportional to Q2
1.
2.
3.
Frequency domain representation of periodic signals is done by A
Fourier Transform
B
Fourier Series
C
Laplace Transform
D
Z-transform
Z –transform of unit sample is A
1
B
0
C
z
D
1/z
Discrete Fourier Transform is A
4.
5.
Discrete in Frequency B Continuous in frequency domain domain C Can be discrete or D None of the above continuous Continuous –to-discrete conversion is achieved by a process of A
sampling
B
filtering
C
inversion
D
multiplication
2 kHz sinusoidal signal is to be sampled. What should be the sampling interval? A 4 msec B 0.25 msec C
6.
2.5 msec
D
5 msec
z-transform evaluated on unit circle C z-transform evaluated at origin Fourier series is a/an
B D
z-transform evaluated outside unit circle None of the above
A
B
Infinite series
Discrete time fourier transform is A
7.
Finite series
C 8.
Waveform dependent D None of the above finite or infinite series Fourier transform represents following type of signals in frequency domain A Periodic signals B Aperiodic signals C
9.
10.
Quasi-periodic signals
D
All of the above
For causal system, A
h(n)=0 for n<0
B
h(n)=0 for n>0
C
h(n)=1 for n<0
D
h(n)=1 for n>0
For an LTI system, if x(n), h(n) and y(n) are input, impulse response and output of the system, which one of the following is true? A y(n)=h(n) x(n) B y(n)=h(n)*x(n) C
h(n)=x(n) y(n)
D
x(n)= h(n)y(n)
11.
Laplace transform is used for the analysis of A
Continuous time system
B
Discrete time system
C
12.
13.
14.
15.
Both continuous time D None of the above and discrete time systems Under force-current analogy ,displacement is analogous to A
Voltage
B
conductance
C
Magnetic flux linkage
D
capacitance
The Laplace transform of e-at is A
1/s
B
1/(s+a)
C
s/(s+a)
D
a/(s+a)
Transfer function can be obtained from A
Analogous table
B
Standard block system
C
Output-input ratio
D
Signal flow graph
Fast Fourier transform algorithm exploits A
16.
Symmetry property of WN C Both symmetry and periodicity property of WN An impulse train is
B
Periodicity property of WN
C
Addition property of WN
A
B
A number of pulses spaced from each other None of the above
Number of pulses
C 17.
A number of pulses all D originating together The integral of a unit step function is A
A unit impulse function
B
A unit pulse function
A ramp function of slope 1 The area of an impulse is
D
None of the above
A
1
B
0
C
infinity
D
indefinite
B
Has a period π
D
Has a period 2 π,decays with increasing x, is an even function and has zeros at nπ,n=(+/-) 1,2,3….
C 18.
19.
The function sinx / x A
C
Has a period 2π ,decays with increasing x and has zeros at nπ ,n=1,2,3,4 Has a period π/2
20.
21.
22.
The function sinc x is equal to A
Sinx/x
B
X sinx
C
x/sinx
D
X+sinx
The autocorrelation of a sampling function is a A
Triangular function
B
Gate function
C
Signum function
D
None of the above
For a periodic waveform, the power spectral density and correlation function form A a Laplace transform pair B a Fourier transform pair C
23.
25.
D
a Hilbert transform pair
The trigonometric Fourier series of an even function of time does not have A dc term B Cosine term C
24.
a z-transform pair
Sine term
D
Odd harmonic terms
The Fourier series of an odd periodic function contains A
Odd harmonics only
B
Even harmonics only
C
Cosine terms only
D
Sine terms only
B
An odd function of τ
Autocorrelation function is A
An even function of τ
C 26.
27.
28.
29.
May be an even or odd D Is both an even and odd function of τ function of τ The inverse Fourier transform of the function 2/jω is A
Sin ωt
B
Cos ωt
C
Sgn (t)
D
u(t)
The period of the function cos (π/4)(t-1) is A
1/8 s
B
8s
C
4s
D
1/4 s
The term energy spectral density is associated with A
Periodic waveform
B
Non-periodic waveform
C
Cosine waveform
D
Exponential waveform
Principle of superposition is applied to A
Linear systems only
B
Non linear systems only
Both linear and non D linear systems For the signum function sgn(t), F(jω)=
SECOND ORDER SYSTEM ONLY
A
2/ jω
C 30.
1/jω
B
C 31.
32.
33.
36.
37.
Non causal system
B
Causal system
C
FIR system
D
Unstable system
y(n)=x(Mn) defines A
multiplier
B
compressor
C
delay
D
accumulator
If f(t) is an even function, the coefficients Fn in the exponential form of Fourier series are A real B imaginary
39.
complex
complex
zeros
D
zeros
A function will have only sine terms if A
f(t)=-f(t)
B
f(-t)=f(t)
C
f(-t)=-f(t)
D
None of the above
One unit of delay in time domain is equivalent to A
z-1 in z-domain
B
z in z-domain
C
z+1 in z domain
D
z-1 in z -domain
Modulation process can be explained by which of the following properties of Fourier transform? A Time shifting B Frequency shifting differentiation
D
integration
Discrete Fourier transform is a/an A
Finite duration sequence
B
Infinite duration sequence
C
Periodic sequence
D
Periodic sequence with period of 2π
Steady state value of system output C Transient behavior of output If f(t) is in volts, F(jω) is in
B
Initial value of output
D
None of the above
A
volts
B
Volts*sec
C
Volts/sec
D
Volts*sec2
Final value theorem is used to find A
40.
D
If f(t) is an odd function, the coefficients Fn in the exponential form of Fourier series are A real B imaginary
C 38.
2 jω
A
C 35.
D
Ideal LPF is
C 34.
jω
41.
Undersampling of the signal results in A
42.
Aliasing in frequency B Aliasing in time domain domain C Aliasing in both time D Preemphasis of the signal domain and frequency domain Even with Nyquist rate sampling, we cannot recover signal without distortion ,because A Filters are non-ideal B Sampling signal is non-ideal C
43.
44.
45.
46.
Multipliers are non ideal
D
All of the above
Reconstruction of a signal from its sampled version requires A
Low pass filter
B
High pass filter
C
Notch filter
D
Band reject filter
The discrete time signal x(n)=(-1)n is periodic with fundamental period A
6
B
4
C
2
D
1
The Fourier transform of an exponential signal x(n)=ejωot is A
A constant
B
A rectangular pulse
C
An impulse
D
A series of impulses
The autocorrelation function of a rectangular pulse of duration T is A
47.
B a rectangular pulse of a rectangular pulse of duration T. duration 2T. C D a triangular pulse of a triangular pulse of duration T. duration 2T. The Fourier Transform of a rectangular pulse existing between t = -T / 2 to t = +T / 2 is a A B sinc squared function. sinc function. C
48.
49.
D
sine function.
The system characterized by the equation y(t ) = ax(t )+ b is A
Linear for any value of b
B
Linear if b>0
C
Linear if b<0
D
Non-linear
If G(f) represents the Fourier Transform of a signal g (t), which is real and odd symmetric in time, then G (f) is A complex B imaginary C
50.
sine squared function.
real
D
Real and non-negative
A band pass signal extends from 1 KHz to 2 KHz. The minimum sampling frequency needed to retain all information in the sampled signal is A 1 kHz B 2 kHz
C 51.
53.
54.
55.
Negative of each other
D
Complements of each other
dx(t )/ dt will be A dX(f)/df
B
j2πf X(f ).
C
D
X(f )/(jf ).
jf X(f)
Inverse Fourier transform of u(ω) is A
0.5 δ(t)+1/(πt)
B
δ(t)+1/(πt)
C
0.5 δ(t)+1/(2πt)
D
δ(t)+1/(2πt)
The impulse response of a system is h(n) =a n u(n) . The condition for the system to be BIBO stable is A
a is real and positive
B
A is real and negative
C
|a|>1
D
|a|<1
If R1 is the region of convergence of x (n) and R2 is the region of convergence of y(n), then the region of convergence of x (n) convoluted y (n) is A B R1+R2 . R1-R2 . R1∩R2 .
D
R1υR2 .
The continuous time system described by y(t)= x(t2) is A C
57.
4 kHz
The Fourier transform (FT) of a function x (t) is X (f). The FT of
C 56.
D
Two sequences x1 (n) and x2 (n) are related by x2 (n) = x1 (- n). In the zdomain, their ROC’s are A The same B Reciprocal of each other C
52.
3 kHz
causal, linear and time varying. non causal, non-linear and time-invariant.
B D
causal, non-linear and time varying. non causal, linear and time-invariant.
The signals x1(t ) and x2(t ) are both bandlimited to –ω1 to + ω1 and –ω2 to + ω2 respectively. The Nyquist sampling rate for the signal x1(t ) x2(t ) will be
58.
59.
A
2ω2
B
ω2
C
2(ω1 + ω2)
D
2 ω1
The signal x(n)=sin(πn/4) is A
aperiodic
B
Periodic with period 8
C
Periodic with period 12
D
Periodic with period 2
Minimum period of discrete time periodic signal is A
1
B
2
C 60.
61.
62.
63.
64.
65.
66.
67.
68.
69.
70.
3
D
4
Maximum frequency (rad/sample) of discrete time signal is A
π
B
π/2
C
2π
D
π/4
The derivative of unit step function is A
Unit impulse
B
Ramp with slope 1
C
impulse
D
Rectangular function
If a periodic function f(t) of period T satisfies f(t)=-f( t + T/2) , then in its Fourier series expansion, A B the constant term will there will be no cosine be zero. terms. C D there will be no sine there will be no even terms. harmonics. A vertical line in s-plane corresponds to A
A line in z-plane
B
A point in z-plane
B
An ellipse in z-plane
D
A circle in z-plane
For a right sided sequence, the ROC of its z-transform will be A
Exterior of a circle
B
Interior of a circle
C
Ring
D
Unit circle in z-plane
For a left sided sequence, the ROC of its z-transform will be A
Exterior of a circle
B
Interior of a circle
C
Ring
D
Unit circle in z-plane
For a two sided sequence, the ROC of its z-transform will be A
Exterior of a circle
B
Interior of a circle
C
Ring
D
Unit circle in z-plane
Frequency response and impulse response are a A
z-transform pair
B
Fourier transform pair
C
Inverse z-transform pair
D
DFT pair
In z-plane, |z|=1 is A
A circle
B
A line
C
A square
D
A rectangle
The ROC of z-transform can not contain any A
zeros
B
C
Poles and zeros
D
Discrete Fourier transform represents
poles
71.
72.
A
Time samples
B
Period information
C
Frequency samples
D
All of the above
In z-transform, if x(n)↔X(z), then nx(n) ↔ A
-zdX(z)/dz
B
dX(z)/dz
C
-zdz
D
zdX(z)/dz
In computation of N- point DFT, there are A
73.
74.
75.
76.
N complex B multiplications C N/2 complex D multiplications Circular convolution is also known as
2N complex multiplications
A
Linear convolution
B
Periodic convolution
C
Simple convolution
D
None of the above
If x(n)={1,1,1,1}, its 4-point DFT coefficient X(0) is A
0
B
4
C
1
D
2
A
Sampled version of DTFT
B
Integrated version of DTFT
C
Same as DTFT
D
Same as z-transform
DFT is
The frequency of a continuous time signal x (t) changes on transformation from x (t) to x (a t), a > 0 by a factor A a B 1/a C
77.
78.
79.
80.
N2 complex multiplications
a2
D
a0.5
If x(n) is of finite duration, then its z-transform will be possibly A
Unit circle
B
ring
C
Entire z-plane
D
origin
For DTFT to exist, the ROC must include A
Unit circle
B
origin
C
Point (-1,1)
D
None of the above
The ROC of z-transform must be A
A discontinuous region
B
A connected region
C
Unit circle
D
Entire z-plane
For a discrete time signal, dimension of ωo is A
degrees
B
radians
C
Radian/sample
D
Degrees/sec
81.
82.
83.
For discrete time signal, high frequencies are closer to A
π
B
0
C
2π
D
π/2
Period of DTFT is A
2π
B
π
C
π/2
D
π/4
If we sample continuous signal x(t)=sin(200 πt) with T=1/400 second, discrete time signal will be x(n)= A Sin(πn/2) B Sin(πn/4) C
84.
Sin (nπ/8)
D
Sin (π/2n)
Discrete Time Fourier Transform is a A
85.
86.
87.
88.
89.
90.
91.
Periodic function in time B Aperiodic function in time domain domain C Periodic function in D Aperiodic function in frequency domain frequency domain The LTI system with impulse response h(n)=4n u(n) is A
stable
B
unstable
C
Non-causal
D
FIR system
To generate cos (πn/3) from cos (4000 πt) by sampling, T must be A
1200
B
12000
C
120
D
12
If y(n)=log(x(n)), the system is A
linear
B
Non-linear
C
LTI
D
None of the above
The correlation of the function with itself is called A
autocorrelation
B
Cross correlation
C
Power spectral density
D
Energy spectral density
Autocorrelation function exhibits A
Conjugate asymmetry
B
Nonlinearity property
C
Compression of signal
D
Conjugate symmetry
Any periodic waveform can be expressed by A
Fourier series
B
Fourier transform
C
z-transform
D
Discrete Fourier Transform
Ideal delay system is characterized by A
y(n)=x(n)
B
y(n)=x(n+no)
C 92.
93.
y(n)=x(n-no)
D
y(n)=x(-no)
B
Integrated to get DFT
DTFT can be A
Sampled to get DFT
C
Differentiated to get DFT D
sampling A
94.
95.
Causes loss of B information C Is a step for D discretization To prevent aliasing, signal should be
Is non-invertible operation
A
oversampled
B
undersampled
C
Critically sampled
D
None of the above
B
Samples of z-transform
D
All of the above
All of the above
DFT samples are A C
96.
None of the above
Equi-spaced on unit circle Finite in number
Duration of DFT sequence should be A
97.
98.
99.
100.
Greater or equal to B Less than the duration of duration of time domain time domain sequence sequence C Equal to Half the D infinite duration of time domain sequence No. of DTFT samples possible on unit circle are A
finite
B
infinite
C
N
D
2N
DFT is normally a A
Real number
B
Imaginary number
C
Complex number
D
Integer number
A
Cannot be computed
B
Can be computed
C
Can be computed for finite duration sequence
D
Can be computed for infinite duration sequence
DFT only
B
DTFT only
DTFT
FFT is A C
101.
DFT computed with less D z-transform sample only no. of computations In force voltage analogy, the quantity analogous to spring constant K is A
R
B
C
C 102.
L
D
1/C
Mechanical impedance is the ratio of A
103.
104.
105.
Rms force to rms B Rms force to rms velocity displacement C Rms velocity to rms D None of the above displacement In force current analogy, displacement is analogous to A
charge
B
Magnetic flux linkage
C
Electrostatic energy
D
voltage
Time rate of change in heat energy is analogous to A
voltage
B
charge
C
current
D
Voltage gradient
An amplifier with adjustable gain C An amplifier with infinite gain In an integral controller,
B
An integrating amplifier
D
An amplifier with almost zero gain
A
B
The rate of change of output is proportional to input None of the above
A proportional controller is basically A
106.
The output is proportional to input
C
107.
108.
109.
110.
111.
The output is D proportional to rate of change of input Which control action is called rate control ? A
proportional
B
derivative
C
integral
D
Proportional plus integral
Which control action can never be used alone? A
proportional
B
derivative
C
integral
D
Both derivative and integral
For a type I system and unit step input, the steady state error is A
0
B
1
C
infinity
D
1/Kp
For a type I system and unit parabolic input, the steady state error is A
0
B
1
C
infinity
D
1/Kv
For a type 0 system and unit ramp input, the steady state error is A
0
B
1
C 112.
infinity
D
1/Kv
The frequency at which phase angle is 180 ˚ is called A
113.
114.
Phase cross over B Stability limit frequency frequency C Frequency of limited D Gain margin frequency stability The system has high gain and phase margins. The system is A
Very stable
B
sluggish
C
Very stable and sluggish
D
oscillatory
B
Gain margin is close to 1
Gain margin is close to 1 or phase margin is zero Integral control action
D
Gain margin is high and phase margin is 180˚
A
Removes offset
B
C
Both A and B
D
May lead to oscillatory response Neither A nor B
A system is highly oscillatory if A
Gain margin is high
C 115.
116.
The addition of a pole to the open loop transfer function pulls the root locus A To the right B To the left C
117.
Marginally stable
Speeds up the transient response C Increases the stability margin and speeds up the transient response The root locus branches A
120.
Towards infinity
D
Highly stable
B
Increases the stability margin None of the above
A lead compensator A
119.
D
A system has its two poles on the negative real axis and one pair of poles lies on jω axis. The system is A stable B unstable C
118.
Towards zero
D
Start from open loop B Start from open loop zeros poles and terminate at and terminate at poles zeros C May start from pole or D None of the above zero and terminate at another pole or zero If zeros at infinity are included in count, the number of zeros of G(s)H(s) is A Equal to number of B One more than number of poles poles C One less than number of D Two more than number of poles poles
121.
In root locus analysis, the breakaway and break in points A
Lie on the real axis
C 122.
Always occur in complex conjugate pairs In a minimum phase system,
B
D
A
123.
All poles lie on the real B axis C All poles and zeros lie in D the left half plane The angular location of poles depends on
All zeros lie in the left half plane All except one pole or zero lie in the left half plane
A
B
Damping ratio
D
Capacitance alone
C 124.
126.
D
medium
A
large
B
small
C
infinite
D
zero
The distance of poles from origin depends on
C
128.
Very small
From the view point of noise, bandwidth should be
A
127.
Undamped natural frequency Resistance alone
If a system is to follow arbitrary inputs accurately, the bandwidth should be A large B small C
125.
Either lie on the real axis or occur in complex conjugate pairs None of the above
Undamped natural frequency Both A and B
B
Damping ratio
D
None of the above
If poles lie in the first quadrant, damping ratio is A
1
B
More than 1
C
Less than 1
D
zero
B
Has a negative dB value
The gain margin for a stable system A
Has a positive dB value
C 129.
Has a large negative dB D Has zero dB value value A thermometer requires 1 minute to indicate 98% of its final response to a step input. If it is a first order system, the time constant is A 1 minute B 0.5 minute C
130.
0.25 minute
D
0.1 minute
A lead compensator is basically a A
High pass filter
B
Low pass filter
C
Band stop filter
D
Band reject filter
131.
A lag compensator provides attenuation in A C
132.
Very low frequency range High frequency range
B
Low frequency range
D
None of the above
PID controlled system has A
133.
P and I actions in B forward path and D action in feedback path C All 3 actions in forward D path The ac motor used in servo application is
P and I actions in feedback path and D action in forward path All 3 actions in feedback path
A
B
Two phase induction motor
D
Synchronous motor
C 134.
135.
Single phase induction motor 3 phase induction motor
Optical encoders most commonly used in control systems are A
Absolute encoders
B
Secondary encoders
C
Incremental encoders
D
None of the above
B
Constant phase angle loci
Nichols chart consists of A
Constant magnitude loci
C
136.
Magnitude and phase D None of the above angle loci in logmagnitude versus phase diagram As the bandwidth increases, the cost of components A
Generally decreases
B
Generally increases
C 137.
138.
139.
140.
May increase or D Does not change decrease The effects of adding poles and zeros can be determined quickly by A
Nichol’s chart
B
Nyquist plot
C
Bode plot
D
Root locus
Magnetic amplifier is used for A
Voltage amplification
B
Power amplification
C
Current amplification
D
Frequency multiplication
Robotic manipulator arms mostly use A
Hydraulic actuator
B
Pneumatic actuator
C
Electric motor actuator
D
None of the above
Integral error compensation changes a second order system to A
First order system
B
Third order system
C 141.
Fourth order system
D
Higher order system
The effect of negative feedback on distortion and bandwidth are A
Both are decreased
B
Both are increased
C
142.
Distortion is reduced D Distortion is increased and and bandwidth is bandwidth is decreased increased If feedback factor is β, the overall gain of a closed loop system is approximately A 1/ β B β C
143.
β2
D
β+A
In a second order system, peak overshoot is independent of A
Damping factor
B
Natural frequency
C 144.
145.
Both natural frequency D Neither natural frequency and damping factor nor damping factor In a second order undamped system, the poles are on A
Positive real axis
B
Imaginary axis
C
Negative real axis
D
origin
The polar plot of G(s)=1/[(1+s)(1+2s)] A
Does not cross real axis
B
Crosses real axis
C 146.
147.
Crosses real axis at D Crosses real axis at ω=1.4 ω=0.7 rad/sec rad/sec At corner frequency, the phase angle of factor 1/(1+jωT) is A
90˚
B
-90˚
C
45˚
D
-45˚
In log magnitude Bode plot ,the slope of high frequency asymptote of (1+jωT) is A 20 dB/ decade B 10 dB/decade C
148.
20 dB /octave
D
10 dB/octave
A conditionally stable system has A
149.
One phase cross over B Two phase cross over frequency frequency C Two or more phase D Zero phase cross over cross over frequencies frequency A system has 12 poles and 2 zeros. Its high frequency asymptote in its magnitude plot has a slope of A -200 dB/decade B -240 dB/decade C
150.
-280 dB/decade
D
-320 dB/decade
B
Inaccuracy of parameters
Modeling error can occur due to A
Neglecting non linear characteristics
C
Change of plant characteristics with time
D
Any of the above
1
An abrupt p-n junction diode in thermal equilibrium at T = 300 K is doped such that Ec – EF = 0.21 eV in the n-region and EF- EV = 0.18 eV in the p-region. The built-in potential barrier Vbi is A 0.69 V B 0.83 V C
2
3
4
5
6
7
0.61 V
D
0.88 V
A silicon p-n junction at T = 300 K has ND = 1014 cm-3 and NA =1017 cm-3. The built-in voltage is A
0.63 V
B
0.93 V
C
0.026 V
D
0.038 V
An p-n junction diode is operating in reverse bias region. The applied reverse voltage, at which the ideal reverse current reaches 90% of its reverse saturation current, is
A
59.6 mV
B
2.7 mV
C
30.4 mV
D
12.0 mV
An abrupt silicon pn junction at zero bias and T = 300 K has dopant concentration of NA =1017 cm-3 and ND = 5 x 1015 cm-3, The Fermi level on n - side is A
0.1 eV
B
0.2 eV
C
0.3 eV
D
0.4 eV
An ideal p-n junction diode is operating in the forward bias region. The change in diode voltage, that will cause a increase in current by factor of 9, is A
83 mV
B
59 mV
C
43 mV
D
31 mV
A transition region in an open circuited p-n junction contains A
free electrons only
B
holes only
C
both free electrons and holes
D
uncovered immobile impurity ions
In unbiased p-n junction, the junction current at equilibrium is A C
due to diffusion of majority carriers zero due to equal and opposite currents crossing the junction
B
due to diffusion of minority carriers
D
zero because no charges cross the junction
8
In the energy band diagram of an open circuited p-n junction, the energy band of nregion has shifted relative to that of p-region A
downward by qVbi
B
upward by qVbi
C
downwards by ( qVbi )/2
D
upwards by ( qVbi )/2
9
10
11
12
The reverse saturation current in germanium diode varies as (where T is the temperature in deg K) A
T
B
T1.5
C
T2
D
1/T
The reverse saturation current in silicon diode varies as (where T is the temperature in deg K) A
T
B
T1.5
C
T2
D
1/T
In a p-n junction diode for constant value of current at room temperature dV/dT varies approximately at the rate of A
-2.5 mV/deg C
B
2.5 mV/deg C
C
-25 mV/deg C
D
25 mV/deg C
In a step graded reverse biased junction the width W of the depletion layer varies as A
13
B
1 In a linearly graded reverse biased junction the width W of the depletion layer varies as C
D
A
B
1 In any p-n junction diode the transition capacitance CT varies as ( where
is the width of the depletion layer) C
14
/
D
B
1 C D √
The built in potential in a p-n junction diode equals A
15
A C 16
B D
ln ln
Pinch off voltage VP for an FET is the drain voltage at which A C
17
ln ln
significant current starts B flowing all free charges get D removed from the channel
drain current becomes zero avalanche break down takes place
The % load regulation in a rectifier output circuit is defined as − − A 100% B 100% + − + C 100% D 100% −
18
A C
!
value for the half wave rectifier circuit can be given by B 2 √2 2 D # #
19 29
20
21
22
23
24
25
26
27
28
For the below circuit waveform for the input is given. The diode in $ value for the half wave rectifier circuit canvoltage be given by circuit has cutin voltage Vγ = 0. Choose the option for the waveform of output voltage ' . B A 2 √2 2 C D # # ! value for the full wave – center tapped rectifier circuit can be given by B A 2 √2 2 C D # # $ value for the full wave – center tapped rectifier circuit can be given by A B 2 √2 2 C D # # The transformer utilization factor (TUF) for the half-wave rectifier is A
0.406
B
0.286
C
0.693
D
0.512
The transformer utilization factor (TUF) for thefull-wave rectifier is A
0.406
B
0.286
C
0.693
D
0.512
The ripple factor (γ) for the half-wave rectifier is A
1.41
B
0.48
C
1.11
D
1.21
The ripple factor (γ) for the full-wave rectifier is A
0.48
B
0.68
C
0.28
D
1.21
The rectification efficiency (η) for the half-wave rectifier is A
23.1%
B
40.6%
C
46.1%
D
20.1%
The rectification efficiency (η) for the full-wave rectifier is A
68.1%
B
81.2%
C
40.6%
D
92.1%
In half wave rectifier, the lowest ripple frequency is A C
%/2 2%
B D
%
3%
30
31
A
B
C
D
For the below circuit waveform for the input voltage is given. The diode in circuit has cutin voltage Vγ = 0. Choose the option for the waveform of output voltage ' .
A
B
C
D
In the circuit of the following figure, D1 and D2 are ideal diodes. The current ( and ( are
A
0, 4 mA
B
4 mA, 0
C
0, 8 mA
D
8 mA,
32
33
34
35
For the circuit shown the figure given below the input voltage ' . Assume the RC time constant large and cut-in voltage of diode ) = 0. The output voltage ' is
A
B
C
D
In the circuit of the figure given below, the diodes have cut-in voltages of 0.6 V. The diode in ON state are
A
only D1
B
only D2
C
both D1 and D2
D
none of the above
A
6.25 kΩ
B
12.50 kΩ
C
25 kΩ
D
None of the above
For the circuit shown in the figure below, diode cut-in voltage ) = 0. The maximum ripple voltage is 4 V. The minimum load resistance, that can be connected to the output is
In the voltage regulator circuit in figure given below the maximum load current (+ that can be drawn is
A
1.4 mA
B
2.3 mA
C
1.8 mA
D
2.6 mA
36
37
38
A Tunnel diode is p-n diode with A
very high doping in p-region
B
very high doping in n-region
C
very high doping in both p-region and n-region
D
low doping in both p-region and n-region
In a Tunnel diode, the depletion width is order of A
100 A0
B
0.1 micron
C
1 micron
D
5 micron
In a Tunnel diode, the impurity concentration is of the order of A
1 in 103
B
1 in 105
C
1 in 107
D
1 in 109
39
The most important application of Tunnel diode is A
as rectifier
B
as switching device in digital circuits
as voltage controllable D as oscillator device In a Varactor diode using the alloy junction, the transition capacitance is proportional to (where is the magnitude of reverse junction voltage) 1 A B 1 1 D C , C
40
41
42
Zener breakdown results basically due to A
impact ionization
B
C
emission of electrons
D
strong electric field across the junction high thermal energy of the electrons
The dynamic resistance of the Zener diode increases with increase of decreases with the increase of B its current current is almost independent of C D none of these current At 250 C, a Zener diode is rated at 2 Watts, its power rating at 500 C will be A
43
44
A
2 Watts
B
1 Watts
C
greater than 2 Watts
D
much greater than 2 Watts
The ON resistance rd ON , of an FET is the ratio : A C
-./ at the origin 0. ∆-./ in the saturation ∆0.
B D
region
45
in the saturation region
-2/ 0.
at the origin
The saturation Drain current 3 in an FET equals A C
46
-./ 0.
33 41 −
53 7 6
33 891 −
53 : 6
B D
33
53 41 − 7 6
33 41 −
53 7 6
The transconduction ; of an FET in the saturation region equals A C
33 53 41 − 7 6 6 33 53 / −2 41 − 7 6 6 −2
B D
−2
33 53 41 − 7 6 6
< . >/ 6 33
47
48
Input resistance of a JFET is of order of A
1 kΩ
B
10 kΩ
C
10 MΩ
D
100 MΩ
Main drawback of a JFET is A
high input impedance
B
low input impedance
C
higher noise
D
lower gain
49
50
51
52
In a PNP transistor operating in the active region, the concentration of minority carrier holes in the n-region at collector junction JC is thermal equilibrium value A zero B ? of emitter thermal equilibrium C concentration of holes in D same as junction JE collector region As the magnitude of the collector junction reverse bias increases, the effective base width A
increases
B
decreases
C
remain same
D
first increases then becomes constant
Transistor α approaches unity when : (Where @A and @B are the conductivities of Base and Emitter regions respectively) @A @A =1 ≫1 A B @B @B @A @A ≪1 =5 C D @B @B In a BJT , as the conductivity of the base increases, the punch through voltage A
53
54
55
56
remains same
B
increases
may increase or decrease depending on the bias at junction JE The dynamic emitter resistance of a BJT operating in the active region is of the order of C
decreases
D
A
0.01 Ω
B
1 Ω
C
100 Ω
D
10 kΩ
In a BJT the, F may be expressed in terms of G as G G A B 1+G 1−G 1+G 1−G C D G G In cut off region operation of BJT (where JE and JC are the Emitter and Collector junctions respectively) both JE and JC are both JE and JC are reversed A B forward biased biased JE is forward bias and JC JC is forward bias and JE is C D is reversed biased reversed biased In a BJT, with HI = 1 JK and G = 0.99 the value of HBI is A C
0.01 JK 1 JK
B
D
0.1 JK
100 JK
57 66
58
59
60
61
62
In a BJT, The common with G emitter = 0.98 short the value circuitofcurrent F is gain β of a transistor A
49
B
98
C
0.49
D
980
A
99
B
0.99
C
1.0
D
1.01
In a BJT, with F = 100 the value of G is
In a BJT, the spreading resistance is in the order of A
10 Ω
B
100 Ω
C
1 Ω
D
1 kΩ
A
base and emitter leads
B
collector and emitter leads
In a transistor current HAI flows in
emitter, base and collector leads In an ideal BJT, the impurity concentration in the emitter (E) , base (B) and collector (C) are such that C
base and collector leads
D
A
E>C>B
B
B>C>E
C
C>E>B
D
E=C>B
The ‘h’ parameter equivalent circuit of BJT is valid for A C
63
D
B = G H + HBI
B B = G H + HI
B = G H + HBI NO P-QR /S − 1> Typical values of h-parameters, at about 1 mA collector current , for small signal audio transistors in CE configuration are: C
A
C 65
low frequency, large signal operation low frequency, small signal operation
B
The Ebers-Moll equation for B in CB configuration is given by A
64
high frequency, large signal operation high frequency, small signal operation
B = G H + HI NO P-QR /S − 1T W
ℎV = 100 ℎ V = 10 ℎXV = 50 ℎ V = 1 JY ℎV = 5 Z ℎ V = 0 ℎXV = 20 ℎ V = 3 JY
B
D
W[
ℎV = 5 Z ℎ V = 10 ℎXV = 200 ℎ V = 20 JY
D
ℎV = 100 Z ℎ V = 10 ℎXV = 100 ℎ V = 10 JY
The modulation of effective base width by collector voltage is known as Early voltage. Hence, reverse collector voltage A
increases both α and β
B
decreases both α and β
C
increases α and decreases β
D
increases β and decreases α
A
C 67
The G - cut off frequency of a BJT A C
68
69
70
71
72
73
74
is a monotonically increasing function of the collector current IC increases with IC for low IC reaches maximum and then decreases increases with the increase in base width increases with the increase in temperature
B
is a monotonically decreasing function of the collector current IC
D
is not a function of IC
B D
increases with the increase in collector width increases with the decrease in base width
A single IC contains more than 110 logic gates. This forms a case of A
SSI
B
MSI
C
LSI
D
VLSI
C
J = ; . \
D
J = ; . \
A
1 mS
B
1S
C
100 S
D
1000 S
A
1 kΩ
B
10 kΩ
C
500 kΩ
D
100 MΩ
A
10 kΩ
B
500 kΩ
C
10 MΩ
D
100 MΩ
A
0.01 V
B
1V
C
10 V
D
100 V
In a JFET the amplification factor J, transconduction ; , and the dynamic drain resistance \ are related by ; \ J= J= A B \ ; The transconductance ; of a JFET is of the order of
The dynamic resistance \ of the JFET is of the order of the The dynamic resistance \ of the MOSFET is of the order of the The magnitude of the threshold voltage for enhancement mode MOSFET is of the order of
Which is the fastest switching device among the below given A
JFET
B
BJT
C
MOSFET
D
Triode
75
76
77
78
The JFET can operate in A
depletion mode only
B
enhancement mode only
C
either in depletion mode or enhancement mode
D
both in depletion mode or enhancement mode simultaneously
The input gate current of FET is A
a few amperes
B
a few miliamperes
C
afew microamperes
D
negligibly small
Which of the following transistor is most vulnerable against ESD (Elecrostatic discharge) A
NPN transistor
B
PNP transistor
C
JFET
D
MOSFET
B
uses a forward biased junction
A field effect transistor (FET) A
has three p-n junctions
depends on the variation depends on the variation the the magnetic field for its D reverse voltage for its operation operation The drain-source output 3 − 3 characteristic of an n-channel depletion FET has 3 = ?]^(_('O `a(`b` A 3 = 0 at 53 = 0 B at 53 = 0 3 = O;a_('O `a(`b` C D 3 is independent of 53 at 53 = 0 C
79
80
81
82
The V-I characteristics of an enhancement mode MOSFET has A
only an ohmic region
C
an ohmic region at low voltages and saturation region at higher voltages
B
only a saturation region
D
an ohmic region at higher voltages and saturation region at lower voltages
The output V-I characteristics of a BJT has A
only an ohmic region
B
only a saturation region
C
an ohmic region at low voltages and saturation region at higher voltages
D
an ohmic region at higher voltages and saturation region at lower voltages
A Schottky diode clamp is used along with the BJT for A C
reducing the power dissipation
increasing the value of F
B
reducing the switching time
D
reducing the base current
84
85
86
For an n-channel JFET having drain –source voltage constant if the gatesource voltage is increased (more negative) pinch-off would occur for high values of drain saturation value of drain A B current current gate current equal to drain C zero drain current D current A MOSFET is called A
2-terminal device
B
3-terminal device
C
4-terminal device
D
5-terminal device
For MOSFETs, the material used for gate structure is A
highly pure Silicon
B
high purity Silica
heavily doped heavily doped amorphous D polycrystalline Silicon Silicon Consider the following statements: The Threshold Voltage ( > of a n-MOSFET can be lowered by 1. Using thinner gate oxide 2. Reducing the substrate concentration 3. Increasing the substrate concentration Of these statements C
87
88
A
3 alone is correct
B
1 and 2 is correct
C
1 and 3 are correct
D
2 alone is correct
The Threshold Voltage ( > of a n-MOSFET can be increased by increasing the channel decreasing the channel B dopant concentration dopant concentration reducing the gate oxide C D reducing the channel length thickness Which of the following methods of biasing provides the best operating point stability A
89
90
A
two battery bias
B
collector-to-base bias
C
fixed bias
D
self bias
Stability factor S in fixed bias CE amplifier is given by A C
91
F
1 F+1
B D
F+1
Stability factor S in self bias CE amplifier is given by c 1 + dec V A B + cdec + cdec V V cd c d ec 1 + ec V V C D c c d d + ec + ec V V
92
93
94
The thermal resistance f of collector junction of a transistor is given by (where ∆g = temperature deviation and h = average power dissipation h A B ∆g = fh ∆g = f f D C ∆g = ∆g = fh h In a CE amplifier, the thermal runaway is unconditionally avoided if HH HH A B HB = HB > 2 2 HH HH HB = D C HB < 2 √2 The parameter ℎ V of a typical transistor is of the order of A
96
97
98
99
100
B
2.5 10Wl
2.5 10W[
D
A
2.5 µS
B
25 µS
C
250 µS
D
2.5 mS
C 95
2.5 10Wk
2.5 10W
The parameter ℎV of a typical transistor is of the order of
With source resistance RS of 1000Ω, the output impedance of a typical CE amplifier stage is of the order of A
500 Ω
B
5 kΩ
C
50 kΩ
D
500 kΩ
With load resistance of 4 kΩ, the current gain of a typical CB amplifier stage is of the order of A
0.98
B
5
C
50
D
250
In a CE amplifier stage, on introducing a resistor Re in the emitter branch the input resistance Ri A
remains same
B
increases nominally
C
decreases
D
increases very much
Ignoring the biasing network, Darlington emitter follower has input resistance of the order of A
20 kΩ
B
200 kΩ
C
2 MΩ
D
20 MΩ
The current gain of the amplifier stage is lowest in A
CB configuration
B
CE configuration
C
CC configuration
D
same in all configurations
101
102
Transistor amplifier stage has lowest input impedance A
CB configuration
B
CE configuration
C
CC configuration
D
same in all configurations
Current gain of small signal transistor amplifier equals
−ℎX ℎX B 1 + ℎ m+ 1 + ℎ m+ −ℎ ℎ C D 1 + ℎ m+ 1 + ℎ m+ Common collector amplifier has (where c is input resistance and cI is output resistance) A
103
A C 104
C
C
107
108
low c and high cI
decreasing emitter circuit and base circuit resistances decreasing emitter circuit and increasing base circuit resistances
B
increasing emitter circuit and base circuit resistances
D
increasing emitter circuit and decreasing base circuit resistances
is higher than in CE and CB configuration is lower than in CE and CB configuration
B D
depends strongly on the source resistance is independent of the source resistance
In CC amplifier A
output is taken from the collector terminal
B
input and output signals are in phase
C
input resistance is low
D
voltage gain is relatively high
In the high frequency hybrid – π model of CE transistor, the conductance ;dnV equals ; ℎXV B A ℎXV ; ; ℎV C D ℎV ; In the high frequency hybrid – π model of CE transistor, the base spreading \ddn Oquals A C
109
D
low c and low cI
Output resistance of CC amplifier A
106
high c and low cI
B
The current stability of an emitter follower may improved by A
105
high c and high cI
ℎV − \dnV ℎV / ℎXV
B
D
ℎV + \dnV \dnV / ℎXV
In the high frequency hybrid – π model of CE transistor, the typical value of CC is A
3 pF
B
100 pF
C
1000 pF
D
0.01 µF
110
111
112
113
The frequency %o at which the short circuit current gain of a CE amplifier falls to 1⁄√2 of its low frequency value is equal to ;dVn ;dVn A B 2# qH + qV ; ⁄ℎXV C D ;dVn
Parameter % of a transistor is approximately given by ; ; A B qV 2#qV ℎXV 2#q C D %o ; In the high frequency hybrid – π model of CE transistor, the conductance ;d$ accounts for bulk conduction of base leakage conductance in the A B region base region feedback action due to C D none of these base width modulation As collector current IC increases the values of % A
remains constant
B
decreases
increases, reaches decreases, reaches minimum D maximum and then falls and then rise In class-AB amplifier with sinusoidal input , the output current flows for C
114
A
116
117
B
full cycle
slightly Less than half D slightly more than half cycle cycle In RC coupled two stage CE amplifier, reduction in voltage gain at the high frequency range results due to shunt capacitance in the input A coupling capacitor Cc B circuit shunt capacitance in the bypass capacitor in the self C D output circuit bias circuit In RC coupled single stage CE amplifier, the lower 3-dB frequency %+ may be reduced by reducing the value of increasing the value of A B coupling capacitor Cc coupling capacitor Cc reducing the total effective shunt reducing the total effective C capacitance in the output D shunt capacitance in the input circuit of the hybrid-π circuit of the hybrid-π model model The upper 3-dB frequency of n-stage amplifier with non-interacting stages equals %+ A B %+ ,2⁄ − 1 ,2⁄ − 1 %+ C D %+ C
115
half the cycle
118
The presence of emitter circuit bypass resistance adversely affects the A
119
120
122
123
B
mid-band response
response over all frequency range When multistage amplifier the coupling method which is capable of providing highest gain is C
high frequency response
D
A
RC coupling
B
Direct coupling
C
Transformer coupling
D
Impedance coupling
In the output of a Push-Pull amplifier most disturbing harmonic distortion is the fundamental frequency A B first harmonic distortion C
121
low frequency response
third harmonic
D
fourth harmonic
Which of the following amplifier produces least distortion A
Class-A
B
Class-B
C
Class-C
D
Class-AB
Which of the following amplifier produces highest distortion A
Class-A
B
Class-B
C
Class-C
D
Class-AB
Compared to single ended amplifier, a push-pull amplifier offers less distortion and less less distortion and more B output power output power more distortion and less more distortion and more D C output power output power In a class-C amplifier, full cycle conduction of the current can be achieved by employing A
124
125
A
transformers
B
Push-pull circuit
C
Tuned circuit
D
Complementary pair
In a feedback amplifier, de-sensitivity D equals A
B
1 + KF
D
A
tends to decrease the output resistance
B
C
does not change the output resistance
D
C 126
KF
1 − KF 1 1 + KF
In a negative feedback amplifier, current sampling
tends to increase the output resistance produces same effect on the output resistance as voltage sampling
127 134
128
129
FET source at Frequency follower which the is a gain negative of the feedback Op-Ampamplifier is zero dBusing called A
Voltage series feedback
B
Current series feedback
C
Voltage shunt feedback
D
Current shunt feedback
BJT RC phase shift oscillator has angular frequency of oscillation ω equals 3 1 1 B A cq √6 + 4 cq 1 1 1 1 C D cq √29 cq √6 + 4 In BJT Colpitts oscillator angular frequency of oscillation ω equals tu A B v v tu 1 − w. x tu
vw. vx z{ y|{
1 + y
C 130
131
yz{ y|{
tu
1 −
D
yz{ y|{ vw. vx
For sustained oscillations in BJT RC phase shift oscillator with 3-sections } of RC network, the required transistor ℎXV is given by (where = }~ ) 29 ℎXV > 29 A B ℎXV > 44 + 23 + 7 29 29 C D ℎXV > 44 + 7 ℎXV > 4 23 + 7 Following compensation method in amplifier leads to reduction in bandwidth A
Lead compensation
B
Pole-zero compensation
Miller effect D Dominant pole compensation compensation In circuit shown in figure below, the input voltage ' is 0.2 V. The output voltage 'I is C
132
133
A
6V
B
8V
C
-6 V
D
-8 V
A
4V
B
6V
C
-3 V
D
-6 V
Consider the circuit shown below, If ' = 2 V, then output 'I is
135
136
137
138
A
crossover frequency
B
Unity gain crossover frequency
C
Gain margin
D
Phase margin
A
-2 V
B
-1 v
C
-0.5 V
D
0.5 V
A
cut-off
B
saturation
C
normal active
D
reverse active
For the Op-Amp circuit shown in the figure, 'I is
For the BJT circuit shown, assume that the F of the transistor is very large and AB = 0.7 . The mode of operation of the BJT is
The circuit below forms
A
active positive clipper
B
logarithmic amplifier
C
active peak detector
D
active half wave rectifier
A
0.9 V
B
1.19 V
C
2.14 V
D
2.84 V
For the circuit in figure A = H and F = 50. The value of A is
139
The Ton time for the 555 based astable multivibrator is A C
140
C
C
143
144
145
146
147
0.69 cA . q
D
1.44 / . q
B
0.69 . q 1.44cA q
cA . q
D
1.44 / . q 1.44cA q
On time for the pulse when monostable multivibrator triggered can be given by A
142
B
Frequency of the waveform generated in 555 based astable multivirator can be given by A
141
0.69 . q
1.34 c. q c. q
B D
Relaxation oscillator is one which
1.1 c. q 1.7 c. q
A
produces non-sinusoidal output
B
oscillates continuously
C
has two stable states
D
none of the above
A transistor is said to be in quiescent state when A
it is unbiased
B
no signal is applied to it
C
no current is flowing through it
D
emitter junction bias equal to collector junction bias
Effect of cascading several amplifier stages is to A
reduce the overall gain
B
C
increase overall gain and reduce the frequency response
D
reduce overall frequency response decrease overall gain and increase the frequency response
Comparator circuits are used in A
summing
B
integrating
C
differentiating
D
converting sine to square wave
In a multistage amplifier, the intermediate stages are always in A
CB configuration
B
CE configuration
C
CC configuration
D
any configuration
A CB amplifier is characterized by A
low Ai , high AV
B
low Ai , low AV
C
high Ai , high AV
D
high Ai , low AV
148
149
150
Capacitor filter is ideal for currents which are A
small
B
medium
C
large
D
very large
Negative feedback in an amplifier results in A
more gain, more bandwidth
B
more gain, less bandwidth
C
less gain, more bandwidth
D
less gain, less bandwidth
Schmitt trigger circuit is also called A
squaring circuit
B
blocking oscillator
C
sweep circuit
D
astable multivibrator
1
2
3
4
5
6
7
8
9
Resistances can be measured with the help of A
wattmeters
B
voltmeters
C
ammeters
D ohmmeters and resistance bridges
An ammeter is a A
secondary instrument
B
absolute instrument
C
recording instrument
D integrating instrument
The multiplier and the meter coil in a voltmeter are in A
series
B
parallel
C
series-parallel
D none of the above
A potentiometer may be used for A
measurement of resistance
B
C
calibration of ammeter
D all of the above
measurement of current
An ohmmeter is a A
moving iron instrument
B
moving coil instrument
C
dynamometer instrument
D none of the above
For measuring a very high resistance we should use A
Kelvin's double bridge
B
Wheat stone bridge
C
Meggar
D None of the above
Which of the following devices should be used for accurate measurement of low D.C. Voltage A
Small range moving coil voltmeter
B
C
Small range thermocouple voltmeter
D None of the above
D.C. potentiometer
A direct current can be measured by A
a D.C. potentiometer directly
B
C
a D.C. potentiometer in conjunction with a volt ratio box
D none of the above
Basically a potentiometer is a device for
a D.C. potentiometer in conjunction with a standard resistance
10
11
12
13
14
A
comparing two voltages
B
measuring a current
C
comparing two currents
D measuring a voltage
In an Anderson bridge, the unknown inductance is measured in terms of A
known inductance and resistance
B
C
known resistance
D known inductance
known capacitance and resistance
For measurements on high voltage capacitors, the suitable bridge is A
Wein bridge
B
Modified De Santy's bridge
C
Schering bridge
D Any of the above
For measurement of mutual inductance we can use A
Anderson bridge
B
Maxwell's bridge
C
Heaviside bridge
D Any of the above
If the current in a capacitor leads the voltage by 80°, the loss angle of the capacitor is A
10°
B
80°
C
120°
D 170°
In a Schering bridge the potential of the detector above earth potential is A
a few volts only
B
1 kV
C
5 kV
D 10 kV
15 If an inductance is connected in one arm of bridge and resistances in the remaining three arms
16
17
A
the bridge can always be balanced
C
the bridge can be balanced if the resistances have D Any of the above some specific values
B
the bridge cannot be balanced
Systematic errors are A
instrumental errors
B
environmental errors
C
observational errors
D all of the above
Standard resistor is made from A
platinum
B
maganin
C 18
19
20
21
22
A
spherical type
B
C
electrostatic type
D multilayer parallel plate type
25
26
concentric cylindrical type
For measurement of inductance having high value, we should use A
Maxwell's bridge
B
C
Hay's bridge
D Any of the above
Maxwell Wein bridge
Volt box is a component to A
extend voltage range
B
C
compare voltage in a box
D none of the above
measure voltage
Wattmeter cannot be designed on the principle of A
electrostatic instrument
B
C
moving iron instrument
D electrodynamic instrument
thermocouple instrument
“Qualitative results” refer to:
C
24
D nichrome
Commonly used standard capacitor is
A
23
silver
Results that can be observed during an experiment. Results that require numerical data.
B
Results that are difficult to observe during an experiment.
D none of these is correct.
The unit of sensitivity is A
Volt
B
Ohm
C
Volt/Ohm
D Ohm/Volt
The basic PMMC movement is often called D’Arsonval movement is used to measure A
DC only
B
AC only
C
Both DC & AC
D
None of the above
The ratio of the change in output of the instrument to a change in input is known as A
Precision
B
Sensitivity
C
Resolution
D
Accuracy
The deviation of the true value from the desired value is known as A
Expected value
B
Output value
C 27
28
29
30
31
32
33
34
35
Error
D Input value
Which of the following are integrating instruments A
Ammeters
B
Voltmeters
C
Wattmeters
D Ampere-hour and watt-hour meters
Which of the following essential features is possessed by an indicating instrument A
Deflecting device
B
Controlling device
C
Damping device
D All of the above
A moving-coil permanent-magnet instrument can be used as _____ by using a low resistance shunt. A
ammeter
B
voltmeter
C
flux-meter
D flux-meter
A _____ device prevents the oscillation of the moving system and enables the latter to reach its final position quickly A
deflecting
B
controlling
C
damping
D any of the above
A moving-coil permanent-magnet instrument can be used as flux-meter A
by using a low resistance shunt
B
by using a high series resistance
C
by eliminating the control springs
D
by making control springs of large moment of inertia
Which of the following devices may be used for extending the range of instruments A
Shunts
B
Multipliers
C
Current transformers
D All of the above
In majority of instruments damping is provided by A
fluid friction
B
spring
C
eddy currents
D all of the above
An ammeter is a A
secondary instrument
B
secondary instrument
C
secondary instrument
D integrating instrument
Self generating type transducers are ___________ transducers.
36
37
A
Active
B
C
Secondary
D Inverse
Strain gauge, LVDT and thermocouple are examples of A
Active transducers
B
C
Analog transducers
D Primary transducers
C
39
40
41
42
43
Passive transducers
A strain gauge is a passive transducer and is employed for converting A
38
Passive
Mechanical displacement into a change of resistance
B
Force into a displacement
D
Pressure into a change of resistance Force into a displacement
Piezo – electric transducers work when we apply _____________ to it. A
Mechanical force
B
C
Illuminations
D
Heat
Vary unequally depending on the core position
Vibrations
In a LVDT, the two secondary voltage A
Are independent of the core position
B
C
Vary equally depending on the core position
D Are always in phase quadrature
The application of LVDT is A
Joint motion
B
Finger movement
C
Limb movement
D Heart wall motion
The resistance of LDR ________________ when exposed to radiant energy. A
Remains unaltered
B
Increases
C
Reaches maximum
D Decreases
Which of the following is a digital transducer A
Strain gauge
B
Encoder
C
Thermistor
D LVDT
The principle of operation of LVDT is based on the variation of A C
Self inductance
Reluctance
B
Mutual inductance
D Permanence
44
45
46
47
48
49
50
51
S1: Transducer is a device which converts physical into electrical quantity. S2: Transducer is also called as sensor. A
S1 is true & S2 is false
B
S2 is true & S1 is false
C
Both S1 & S2 are true
D
Both S1 & S2 are false
The principle of operation of variable resistance transducer is A
Deformation leads to change in resistance
B
Displacement of a contact slider on a resistance
C
Coupling of two coils changes with displacement
D
Movement of magnetic field produces variation in resistance of material
_____________ is the example of photo emissive cell A
LDR
B
Photo diode
C
Photo transistor
D Photo multiplier
B-H Curve is used to determination of: A
Hysteresis loss
B
Iron loss
C
Eddy current loss
D Both (a) and (b
In CRO the time base signal is applied to A
Y-plates
B
X-plates
C
Either X-plate or Y-plate
D
Both X-plate and Y-plate
The main advantage of crystal oscillator is that its output is A
A Constant frequency range
B
C
50 Hz to 60 Hz
D Variable frequency
DC
Hay’s Bridge is suitable for the measurement of: A
Inductances with Q>10
B
Inductances with Q<10
C
Capacitors with high dissipation factor
D
Capacitors with low dissipation factor
A 0 - 100 V volteter has 200 scale divisions which can be read to 1/2 division. Determine the resolutin of the meter in volt. A
0.60 V
B
1V
C
0.92 V
D
0.25 V
Illumination is measured using which one of the following? 52
A
Millivoltmeter
B
Stroboscope
C
Luxmeter
D
pH meter
Which of the following can be measured with the help of piezo electric crystal? 53
A
Force
B
Velocity
C
Sound
D
Pressure
Which of the following is a digital transducer? 54
A
Strain gauge
B
Encoder
C
Thermistor
D
LVDT
The difference between the measured value and the true value is called 55
A
gross error
B
relative error
C
probable error
D
absolute error
The device used to indicate the presence of an electric current is 56
A
Electrometer
B
Galvanometer
C
Voltmeter
D
Coulometer
An average-reading digital multimeter reads 10V when fed with a triangular wave, symmetric about the time-axis.For the same input an rms-reading meter will read 57 A
20/√3
B
10/√3
C
20√3
D
10√3
A voltmeter should have 58
A
Low internal resistance
B
High internal resistance
C
Electrostatic plates
D
A sensitive amplifier
The pressure coil of a dynamo meter type wattmeter is 59
A
Highly inductive
B
Highly resistive
C
Purely resistive
D
Purely inductive
The two inputs of a CRO are fed with two stationary periodic signals. In the X-Y mode, the screen shows a figure which changes from ellipse to circle and back to ellipse with its major axis changing orientation slowly and repeatedly. The following inference can be made from this. 60
A
C
The signals are not sinusoidal The signals are sinusoidal with their frequencies very close but not equal
B
D
The amplitudes of the signals are very close but not equal There is a constant but small phase difference between the signals
In two watt meter method of power measurement, if one of the watt meter shows zero reading, then it can be concluded that 61
A
Power factor is unity
B
Power factor is zero
C
Power factor is 0.5 lagging
D
Power factor is 0.5 leading
A thermocouple 62
A C
Gets warm when dc flows through it Generates ac when heated
B D
Is a thin, straight, special wire Generates dc when exposed to visible light
The shunt type ohm meter is not suitable for high resistance measurements because
63
A
Very low resistance of the meter would short the high unknown resistance
B
Scale is highly cramped for high resistance
C
Full scale value of the meter may D Battery cannot supply the necessary be exceeded current for proper meter deflection The change in value of an analog signal during the conversion process produces what is called the 64
A
quantization error
B
resolution error
C
D sampling error Nyquist error Which of the following performance specifications applies to a sample-and-hold circuit? 65
66
A
Aperture time
B
Aperture droop
C
Feedback
D
Acquisition jitter
Telemetry may be defined as,
A
Drawing graph
B
Indicating direction
C
Calculating length
D
Measuring at a distance
Converting the deflection of an insrument in to impulses of proportional frequency is known as 67
A
Frequency modulation
B
Pulse amplitude modulation system
C
Impulse counting system
D
Impulse frequency system
Strain guage converts 68
A
Mechanical displacement in to a change in resistance
B
Resistance in to a change in mechanical displacement
C
Current in to a change in resistance
D
None of this
In CRT the amount of cathod current, which governs the intensity of the spot, can be controlled with 69
A
The spot screw
B
Holding switch
C
The control grid
D
First anode
In oscilloscope tube electron gun the beam is accelerated to the final velocity by a 70
A
Quadrupole lens
B
Increasing current
C
Control grid
D
Deflection plates
The power factor is the cosine of the angle between 71
A
Voltage and curent
B
Current and inductance
C
Voltage and frequency
D
All of above
A 1 - mA meter movement with an internal resistance of 100 Ω is to be converted in to a 0 - 100 mA ammeter. The value of the shunt resistance required is 72
73
A
9.10 Ω
B
1.01 Ω
C
0Ω
D
10 Ω
Relation of averae value and the rms value of time varying voltages and currents is
A
Power factor
B
Form factor
C
Phase value
D
None of this
Desirable value of temperature coefficient of resistance (α) in resistance temperature detectors is 74
A
Low
B
High
C
Value does not affect sensitivity
D
None of this
Unit of deflection sensitivity of CRT is 75
A
Meter/Volt
B
Volts
C
Volts/Meter
D
Volts/Time
What is crest factor in true rms responding voltmeter 76
A
Ratio of rms value to peak value
B
Ratio of value of current to rms value
C
Ratio of value of current to value of peak value
D
Ratio of peak value to rms value
The output voltage of a typical thermocouple is 77
A
Less than 100 mV
B
Greater than 1 V
C
Thermocouples vary resistance, not voltage
D
None of this
What is the zero-voltage switch used for? A
For extremely low-voltage applications
B
To provide power to a circuit when power is lost
C
To control low-voltage circuits
D
To reduce radiation of high frequencies during turn-on of a high current to a load
78
Temperature sensing can be achieved by the use of 79
A
Thermocouples
B
RTDs
C
thermistors
D
All of the above
The purpose of compensation for a thermocouple is 80 A
to decrease temperature sensitivity
B
to increase voltage output
C 81
82
83
84
85
86
to cancel unwanted voltage output of a thermocouple
D
used for high-temperature circuits
Self generating type transducers are ___________ transducers. A
Active
B
Secondary
C
Passive
D
Inverse
Which of the following instrument can be used for both ac and dc A
PMMC type
B
Moving-iron type
C
Induction type
D
None of the above
Electrostatic instruments are mainly employed to measure: A
Heavy currents
B
Low voltages
C
Low currents
D
High voltages
Measurement range of a voltmeter can be extended by using: A
High current resistance
B
Low shunt resistance
C
High series resistance
D
Low series resistance
_____________ is the example of photo emissive cell A
LDR
B
Photo transistor
C
Photo diode
D
Photo multiplier
The instrument which is cheapest for dc measurement is: A
Moving iron
B
Hot-wire
C
PMMC
D
Electro-dynamo
87
LVDT windings are wound on A
Steel sheets
B
Ferrite
C
Aluminium
D
Copper
88 Which of the following can be measured with the help of piezo electric crystal?
89
A
Force
B
Sound
C
Velocity
D
Pressure
Swamping of resistance is used to compensate error due to: A
Stray magnetic field
B
Large supply variations
C 90
Temperature variations
D
None of the above
Strain gauge, LVDT and thermocouple are examples of A
Active transducers
B
Analog transducers
C
Passive transducers
D
Primary transducers
91 Certain type of materials generates an electrostatic charge or voltage when mechanical force is applied across them. Such materials are called A
Piezo-electric
B
Thermo-electric
C
Photo-electric
D
Photo-resistive
92 The principle of operation of LVDT is based on the variation of
93
94
A
Self inductance
B
Reluctance
C
Mutual inductance
D
Permanence
A transducer that converts measurand into the form of pulse is called A
Active transducer
B
Digital transducer
C
Analog transducer
D
Pulse transducer
An inverse transducer is a device which converts A C
95
C
97
B D
Electrical energy into thermal energy Electrical energy into light energy
The internal resistance for milli ammeter must be very low for: A
96
An electrical quantity into a non electrical quantity Electrical quantity into mechanical quantity
High sensitivity High accuracy
B D
Maximum voltage drop across the meter Minimum voltage drop across the meter
Potentiometer is an __ instrument: A
Indicating
B
Calibrating
C
Comparison
D
Recording
B
When external magnetic field is applied When the junction of two such crystals are heated
Piezo electric crystal can produce an emf A C
When external mechanical force is applied to i When radiant energy stimulates the crystal
D
98
99
Which of the following bridge is frequency sensitive: A
Wheatstone bridge
B
Anderson bridge
C
Maxwell bridge
D
Wien bridge
In wire wound strain gauges, the change in resistance is due to A C
100
change in diameter of the wire Change in length of the wire
B D
Change in both length and diameter Change in resistivity
Voltmeter should be of very high resistance so that: It may draw current minimum A B Its range is high possible C
Its accuracy is high
D
Its sensitivity is high
101 The resistance of LDR ________________ when exposed to radiant energy.
102
103
104
105
A
Remains unaltered
B
Reaches maximum
C
Increases
D
Decreases
Direct current is preferred over alternating current for testing of ac transmission lines and cables because:
A
Heavy charging currents will be drawn and so a large sized transformer is required if tested with ac
B
C
b) Transmission lines and cables should not be tested with dc
D
The transformers required for testing cannot be used for long distances
All the above
The capacitance microphone is used for the detection of A
Heart rate
B
Heart sound
C
Blood flow
D
Foot pressure
The application of LVDT is A
Joint motion
B
Limb movement
C
Finger movement
D
Heart wall motion
A ammeter
B
A multimeter
A voltmeter
D
None of the above
A Ohmmeter is basically:
106
Pressure transducer for measuring blood pressure is A C
107
Strain gauge transducer only Strain gauge or capacitive transducer
B D
Resistive transducer Fiber optic transducer
Test electrode is also known as A
a) Indicator electrode
B
c) Second electrode
C 108
D d) Primary electrode b) Reference electrode A moving iron ammeter coil has few turns of thick wire in order to have: A C
109
a) High sensitivity b) Effective damping
B
c) Low resistance and large current carrying capacity
D
d) Large scale
A thermo-couple instrument can be used for the measurement of: A
a) Direct current only
B
c) Both direct current and alternating current
C 110
111
D d) dc/ac voltage only b) Alternating current only Capacitive transducers are normally employed for___________ measurements A
a) Static
B
c) Transient
C
b) Dynamic
D
d) Both static and dynamic
Which of the following is a digital transducer? A
a) Strain gauge
B
c) Thermistor
C
b) Encoder
D
d) LVDT
Aluminum is a 1
A
Diamagnetic material
B
Ferromagnetic material
C
Paramagnetic material
D
Dielectric material
Relative permeability of Aluminum is 2
3
4
A
1.00000065
B
1.00000079
C
1.00004
D
1.0001
Boltzmann constant is A
1.381 X 1023 J/K
B
1.381 X 10-23 J/K
C
1.381 X 1023 V/K
D
1.381 X 10-23 V/K
Conductivity of Silver used in wave guide is ____mho/meter A
3.82 X 107
B
4.10 X 107
C
5.80 X 107
D
6.17 X 107
Conductivity of Gold used in wave guide is ____mho/meter 5
A
3.82 X 107
B
4.10 X 107
C
5.80 X 107
D
6.17 X 107
IEEE microwave frequency band Ku is in ______GHz range 6
7
8
A
8.000 – 12.000
B
12.000 – 18.000
C
18.000 – 27.000
D
27.000 – 40.000
IEEE microwave frequency band X is in ______GHz range A
8.000 – 12.000
B
12.000 – 18.000
C
18.000 – 27.000
D
27.000 – 40.000
A conductor of _____ conductivity and ____ permeability has low intrinsic impedance. A Low, Low B Low, High C
9
D
High, High
Principle advantage of microwaves over low frequency is A C
10
High, Low
Increased bandwidth
B
Increased privacy
Ability to use high gain, D All of the above high directivity antenna Microwave links are preferred for TV transmission because
A
11
Of small S/N ratio
B
They produce less phase distortion C They are relatively D They are free from impulse cheaper noise Rain drop attenuation in most microwave link is caused due to A
12
13
14
Scattering of microwaves B. Scattering of microwaves by a by water drops of specific collection of droplets acting of size a single body C Absorption of microwave D Absorption of microwaves by by water consequent water vapour in the heating of the liquid atmosphere Standard mismatching in microwave circuits have SWR from A
0.5 : 1 to 2 : 1
B
1 : 0 to 2 : 1
C
1.2 : 1 to 2 : 1
D
1.33 : 1 to 2 : 1
In microwave we take the elements as A
Lumped circuit element
B
Distributed circuit element
C
Both a and b
D
None of the above
Microwave link repeaters are typically 50km apart A
15
16
17
Because of earth B Because of atmospheric curvature attenuation C Because of output tube D To ensure that the applied dc power limitations voltage is not excessive When the free-space wavelength of a signal equals the cut off wavelength of guide A The group velocity of the B The phase velocity of the signal becomes zero. signal becomes infinite C The wavelength within the D All of the above waveguide becomes infinite The front end of the amplifier chain in a manufacturer communication system is kept immersed in liquid nitrogen, to A Dissipate heat generated B Expand its frequency response by amplifier C Improve its noise figure D Reduce the distortion by the amplifier Short-term fading in microwave communication links can be overcome by A
18
Increasing the B Changing the antenna transmitting power C Changing the modulation D Diversity reception and scheme transmission The wavelength of microwave at 100GHz will be
19
20
A
3 cm
B
0.3 cm
C
0.03 cm
D
0.3 m
When microwave signals follows the curvature of the this is known as, A
Ducting
B
Farady effect
C
Tropospheric scatter
D
Ionospheric reflection
B
Is not good low level amplifier because of noise Has a high repeller voltage to ensure small transition time
Multicavity Klystron A
Is not microwave device
C 21
Is not suited for pulse operation A Reflex Klystron functions as
D
A
B
Microwave oscillator
Microwave amplifier
C 22
23
Both as microwave D A high gain cavity amplifier and oscillator A Reflex klystron is capable of generating such high frequencies as A
1000 MHz
B
10000 MHz
C
100000 MHz
D
8 GHz
Cylindrical cavity resonators are not used with klystron because they have A
Too low Q
C
24
A shape not permitting easy adjustment of resonant frequency The modes in a reflex klystron
B D
Harmonically related resonant frequency Are difficult to fabricate
A
25
Give the same frequency B Result from excessive transit but different transit times time across the resonator gap C Are caused by spurious D Are just for theoretical frequency modulation considerations Which of the following microwave tube amplifier uses a coaxial magnetic field and radial electric field? A Coaxial magnetron B CFA C
26
Travelling wave D Reflex Klystron magnetron The secondary cavity in a two cavity klystron is called the A
Buncher cavity
B
Catcher cavity
C
Velocity modulation cavity
D
None of these
27
28
29
Klystron operates on the principle of A
Amplitude modulation
B
Frequency modulation
C
Pulse modulation
D
Velocity modulation
The magnetic field intensity (in A/m ) at the centre of a circular coil of diameter 1 meter and carrying current of 2 A is A
8
B
4
C
3
D
2
The polarization of a dielectric material is given by A
→
→
B
P =∈r E . C
→
→
→
P = (∈r -1 )E . D
→
P = (∈r −1) ∈0
P = E ∈0 (∈r −1) 30
→
In a travelling electromagnetic wave, E and H vector fields are A
perpendicular in space .
B
parallel in space
C 31
E is in the direction of D H is in the direction of wave wave travel travel. For a broad side linear array which of the following is not correct A
C
32
the progressive phase shift ( α) between elements is zero.
D
the maximum radiation occurs along the line of array at ф = 90’
remain the same.
D
decrease by a factor of 2.
In a dielectric-conductor boundary (interface), the tangential component of electric field is A Et B 2Et C
34
B
A wave is incident normally on a good conductor. If the frequency of a plane electromagnetic wave increases four times, the skin depth, will A Increase by a factor of 2. B decrease by a factor of 4. C
33
the maximum radiation occurs perpendicular to the line of the array at ф =90 width of principal lobe is less than that of an end fire array.
Zero
D
Infinite
For a transmission line terminated in its characteristic impedance, which of the following statement is incorrect:
35
36
37
A
It is a smooth line.
B
The energy distribution between magnetic and electric field is not equal. C Standing wave does not D Efficiency of transmission of exist. power is maximum. For a line of characteristic impedance, ZO terminated in a load, ZR such that ZR > ZO , the Voltage Standing Wave Ratio (VSWR) is given by A
ZR/Z0
B
Z0
C
ZR
D
Z0/ZR
The lower cut-off frequency of a rectangular wave guide with inside dimensions (3 × 4.5 cm) operating at 10 GHz is A
10 GHz
B
9 GHz
C
10/9 GHz
D
10/3 GHz
The directive gain cannot be stated as A
38
the ratio of the radiation B the function of angles intensity in that direction to the average radiated power. C the directivity of an D independent of angles antenna when directive gain is maximum. With respect to equi-potential surface pick the odd one out. A
Potential is same every where
B
C 39
40
Potential is different every D where The intrinsic impedance of free space is A
75 ohm
B
73 ohm
C
120 π ohm
D
377 ohm
The characteristic impedance is given by A C
41
Work done in moving charge from one point to another is zero No current flows on this surface
Z0 =
√ .
B D
√ Zsc. Zoc
Transverse electric wave travelling in z- direction satisfies A
Ez = 0; Hz = 0
B
Ez = 0; Hz ≠ 0
C 42
43
Ez 0; Hz ≠ 0.
A
73 Ω
B
75 ohm
C
120 π ohm
D
377 ohm
In an electromagnetic wave, the phase difference between electric and magnetic field vectors E and B is A Zero B Π /2 Π
D
Π/4
Consider a transmission line of characteristic impedance 50 ohms and the line is terminated at one end by +j50 ohms, the VSWR produced in the transmission line will be A +1 B 0 C
45
D
Radiation resistance of a λ/2 dipole is
C 44
Ez ≠ 0; Hz = 0
Infinite
D
-1
Which one of the following conditions will not guarantee a distortion less transmission line A R=0=G B RC = LG C
46
very low frequency range D very high frequency range (R>>wL, G >> wC) (R<
47
Lossless dielectric
D
Perfect conductor
Which of the following statements is not true of waves in general? A
48
It may be a function of B It may be sinusoidal or time only cosinusoidal C It may be a function of D For practical reasons, it must time and space be finite in extent. Plane y=0 carries a uniform current of 30 az mA/m. At (1, 10, –2), the magnetic field intensity is A –15 ax mA/m B 15 ax mA/m C
49
D
18.85 a y nA/m
A loop is rotating about y-axis in a magnetic field B =B0 sin _t ax Wb/m2 . The voltage induced in the loop is due to A Motional emf B Transformer emf C
50
477.5 a y μA/m
A combination of motional D None of the above & transformer emf If ∇×D =Є ∇×E and ∇ × J = б ∇×E in a given material, the material is
said to be
51
52
A
Linear
B
Homogeneous
C
Isotropic
D
Linear & Homogeneous
Lorentz force law is A
F = QE
B
F = V*B
C
F= Q(E + V*B)
D
F = Q (V*B)
For a transmission line terminated by a load, the reflection co-efficient magnitude Γ and the voltage standing wave ration S are related as: A B S = 1 / (1+| Γ| ) S = 1 / (1− |Γ| ) C
53
55
56
D
S = (1+ | Γ | ) / (1− | Γ | )
For a rectangular wave guide, 2.5cm x 1.2cm, dominant cut off wavelength is A 5 cm B 2.5 cm C
54
S = (1− | Γ | ) / (1+| Γ | )
2.4 cm
D
3.7 cm
If a line is terminated in an open circuit, the VSWR is A
0
B
1
C
Infinite
D
-1
A hollow rectangular waveguide acts as a A
High pass filter
B
Low pass filter
C
Band pass filter
D
Low frequency radiator
Divergence theorem is applicable for A
static field only
B
time varying fields only
C 57
both static and time D electric fields only varying fields A uniform plane wave in air is incident normally on an infinitely thick slab. If the refractive index of the glass slab is 1.5, then the percentage of the incident power that is reflected from the air-glass interface is A 0% B 4% C
58
20 %
D
10 %
Some unknown material has a conductivity of mho/ m, and a permeability of 4 * . The skin depth for the material at 1 GHz A 15.9 um B 20.9 um
C 59
61
63
1.386 MHz
15 GHz
D
20 GHz
rate of energy flow.
B
direction of polarization
C
intensity of electric field.
D
intensity of magnetic field.
In an-filled rectangular wave guide, the cutoff frequency of a TE10 mode is 5 GHz where as that of TE01 mode is 12 GHz. The dimensions of the guide is A 3 cm by 1.25 cm B 1.25 cm by 3 cm 6 cm by 2.5 cm
D
2.5 cm by 6 cm
Consider a 150 m long air-filled hollow rectangular waveguide with cutoff frequency 6.5 GHz. If a short pulse of 7.2 GHz is introduced into the input end of the guide, the time taken by the pulse to return the input end is A 920 ns B 460 ns 230 ns
D
430 ns
A rectangular waveguide is filled with a polyethylene Є r=2.25 and operates at 24 GHz. The cutoff frequency of a certain mode is 16 GHz. The intrinsic impedance of this mode is A 224.8 ohm B 337.2 ohm C
66
D
A
C 65
0.6 MHz
Poynting vector gives
C 64
30.9 um
A transmission line with a characteristic impedance 1 Z is connected to a transmission line with characteristic impedance 2 Z . If the system is being driven by a generator connected to the first line, then the overall transmission coefficient will be A B + + C D + + A rectangular waveguide has dimension 1.0 cm×0.5 cm, its cutoff frequency for the dominant mode is A 5 GHz B 10 GHz C
62
D
The radio wave is incident on layer of ionosphere at an angle of 30’ with the vertical. If the critical frequency is 1.2 MHz, the maximum usable frequency (MUF) is A 1.2 MHz B 2.4 MHz C
60
25.9 um
421.4 ohm
D
632.2 ohm
The cross section of a waveguide is shown in fig. It has dielectric discontinuity as shown in fig. If the guide operate at 8 GHz in the dominant mode, the standing wave ratio is
67
A
-3.911
B
2.268
C
1.564
D
4.389
The air filled cavity resonator has dimension a = 3 cm, b = 2 cm, c=- 4 cm. The resonant frequency for the TM110 mode is A 5 GHz B 6.4 GHz C
68
6
4.3 cm
D
8.6 cm
added by 8%
D
removed by 8%
200 sin(Ψt -β z)
D
sin(Ψt -β z)
A lossless transmission line operating at 4.5 GHz has L =2.6 uH m and Z 0= 80Ω. The phase constant β and the phase velocity v is A B 214 rad/m, 30.8* m s 148 rad/m, 274* m s C
73
D
A lossless line has a voltage wave V(z, t) =10 sin(Ψt -β z). The line has parameter L =0.2 uH /m, C= 0.5 nF /m. The corresponding current wave is A 20 sin(Ψt -β z) B 0.5 sin(Ψt -β z) C
72
1
A 81Ω lossless planer line was designed but did not meet a requirement. To get the characteristic impedance of 75Ω the fraction of the width of the strip should be A added by 4% B removed by 4% C
71
9 GHz
A parallel-plate guide operates in the TEM mode only over the frequency range0 < f< 3GHz. The dielectric between the plates is Teflon (Єr =21) . The maximum allowable plate separation b is A 3.4 cm B 6.8 cm C
70
D
Two identical rectangular waveguide are joined end to end where a = 2b. One guide is air filled and other is filled with a lossless dielectric of Єr . it is found that up to a certain frequency single mode operation can be simultaneously ensured in both guide. For this frequency range, the maximum allowable value of Єr is A 4 B 2 C
69
16.2 GHz
919 rad/m, 30.8* m s
D
None of the above
A 60 Ω coaxial cable feeds a 75 + j25 Ω dipole antenna. The voltage
reflection coefficient Γ and standing wave ratio s are respectively
74
A
0.212 ∠48.55’, 1.538
B
0.486 ∠ 68.4’, 2.628
C
0.486 ∠ 41.45’ , 2.628
D
0.212 ∠68.4’, 1.538
For a short-circuited coaxial transmission line: Characteristic impedance Z0 = 35 + j49 Ω , Propagation constant г = 1.4 + j5 Length of line l =0.4 m. The input impedance of short-circuited line is A 82 + j39 Ω B 41 + j78 Ω C
75
79
21.3 Ω
D
169 Ω
0
D
7.707
A lossless transmission line with a characteristic impedance of 80 Ω is terminated by a load of 125 Ω. The length of line is 1.25 λ. The input impedance is A 80 Ω B 51.2 Ω C
78
34 + j23 Ω
Consider a 300Ω quarter-wave long transmission line operating at 1 GHz. It is connected to 10 V, 50 Ω source at one end and is left open circuited at the other end. The magnitude of the voltage at the open circuited end of line is A 10 B 5 C
77
D
The quarter-wave lossless 100 Ω line is terminated by load ZL =210Ω. If the voltage at the receiving end is 60 V, the voltage at the sending end is A 126 Ω B 28.6 Ω C
76
68+ j46 Ω
125 Ω
D
45 Ω
Three lossless lines are connected as shown in fig. The input impedance Zin at A is
A
46 – j 69 Ω
B
39 – j 57 Ω
C
67 + j 48 Ω
D
61 + j 52 Ω
Two λ/4 transformers in tandem are to connect a 50 Ω line to a 75 Ωload as shown in fig. P8.6.34. If Z02 =30Ω and there is no reflected wave to the left of A, then the characteristic impedance Zo1 is
80
81
82
A
28Ω
B
56Ω
C
49Ω
D
24.5Ω
Two identical antennas, each of input impedance 74 Ωare fed with three identical 50Ω quarter-wave lossless transmission lines as shown in fig. The input impedance at the source end is
A
148Ω
B
106Ω
C
74Ω
D
53Ω
The 300Ω lossless line shown in fig. is matched to the left of the stub. The value of ZL is
A
1-j 1.37
B
1+j 1.37
C
300+j413
D
300-j413
A short-circuited stub is connected to a 50 Ω transmission line as shown in fig. The admittance seen at the junction of the stub and the transmission line is
83
A
0.01 – j 0.02
B
0.02 + j0.01
C
0.04 + j0.02
D
0.04 – j 0.02
Frequencies that encompass the 300- to 3000-MHz range are under which of the following segments A high frequency B very high frequency C
84
D
transmission delay
inside diameter
D
velocity factor
standing wave
D
reflected signal
When the load impedance does not exactly match the line impedance and the load has reactive components in addition to its resistance, the line is said to be A open B shorted C
88
transit time
Energy that is reflected from the end of an improperly terminated line back up the line towards the generator is called a A harmonic B stranded wave C
87
microwave
Which of the following is not an important transmission line specification? A impedance B attenuation C
86
D
The time it takes a signal applied at one end of a transmission line to appear at the other end of the line is called A signal time B time constant C
85
ultrahigh frequency
reactive
D
resonant
In an ideal case where there are no standing waves, the standing wave ratio is A 0 B 1 C
100
D
Infinite
89 Which of the following is not used to offset antenna reactance and to
produce an impedance match?
90
A
π LC network
B
C
π RC network
D
92
special lines
Boolean table
D
frequency response curve
dB loss
D
reflection coefficient
A stacked collinear antenna consisting of half-wave dipoles spaced from one another by one-half wavelengths is the A broadside array B end-fire array C
95
D
Which of the following is not found on the linear scales printed at the bottom of Smith charts? A SWR B impedance C
94
PCB lines
Tinier microstrip and striplines made by using monolithic, thin-film, and hybrid techniques when combined with diodes, transistors, and other components form what are called A microstrip integrated B microwave integrated circuits circuits C stripline integrated D high-frequency integrated circuits circuits A sophisticated graph that permits visual solutions to transmission line calculations is the A Karnaugh map B Smith chart C
93
L LC network
Special transmission lines constructed with copper patterns on a printedcircuit board that can be used as tuned circuits, filters, or impedancematching circuits are called A microchip B stripline C
91
T LC network
wide-bandwidth array
D
parasitic array
When the characteristic impedance of the transmission line matches the output impedance of the transmitter and the impedance of the antenna itself, A the SWR will be 10:1 B the SWR will be 1:10 C
96
minimum power transfer D maximum power transfer will will take place take place A one-quarter wavelength of coaxial or balanced transmission line of a specific impedance connected between a load and a source in order to match impedances is A a balun B an autotransformer C
a Q section
D
dummy load
97
Small wire loop inductors and capacitors are used to provide A
low-noise amplification
B
C 98
impedance matching and D tuning Hollow metal conducting pipes designed to carry and constrain the electromagnetic waves of a microwave signal are A wavetraps B waveguides C
99
101
D
tapered wedge
B
klystron
C
horn
D
Cavity resonator
A three-port microwave device used for coupling energy in only one direction around a closed loop is a A circulator B Joint Terminator
D
cavity resonator
Which of the following diodes is not typically used in the microwave region? A point-contact B standard PN standard PN
D
hot carrier
Which of the following diodes does not oscillate due to negativeresistance characteristics? A tunnel B SCR Gunn
D
IMPATT
A thin piece of N-type gallium arsenide or indium phosphide semiconductor which forms a special resistor when voltage is applied to it is the A tunnel diode B PIN diode C
105
choke joint
microstrip
C 104
microwave tubes
A
C 103
D
A waveguide like device that acts as a high-Q parallel resonant circuit is a
C 102
traveling wave tubes
A microwave component which is used to interconnect two sections of waveguide is the A T section B curved section C
100
decoupling to prevent feedback signal coupling
Gunn diode
D
varactor diode
A microwave vacuum tube using cavity resonators to produce velocity modulation of an electron beam which produces amplification is A a klystron B magnetron
C
a cathode-ray tube
D
traveling-wave tube
106
A ship to ship communication system is affected by fading. A useful solution which can be used is A A more directional B Use of space diversity antenna C Use of frequency diversity D A broadband antenna
107
For the experimental study of small microwave antennas, a free space environment with minimum interference by external objects, the facilities required are: A RF screens B slotted waveguides C
108
110
111
112
power meter
4 GHz and 6 GHz
D
6 GHz and 4 GHz
The main disadvantage of using coaxial cable for microwave signals is its A
High sensitivity
B
Low distortion
C
High attenuation
D
Low selectivity
Which of the following introduces mode partition noise? A
Fiber transmission
B
C
Wave guide
D
Fiber transmission
A
stepped index operation
B
attenuation in glass
C
micro-bending
D
impurities
Both coaxial line and wave guide Which of the following does not cause losses in optical fibre cables?
Consider the transmission line of length 37.5cm which is terminated into zero resistance. This line is being excited by a source of 1Ghz which has a internal impedance of 50ohm. What is the input impedance of the line as seen by the source? A infinite B 52ohm C
113
D
In a typical satellite communication system, which of the following could be the up-link and down-link frequencies respectively? A 60 GHz and 40 GHz B 40 GHz and 60 GHz C
109
UHF screens
0 ohm
D
100 ohm
Which device can detect the presence of both forward and backward waves in a wave guide? A directional coupler B detector
C 114
116
117
118
120
121
magic T
1 and 2
D
3 and 4
Which of the following is a microwave source with a cross field structure? A
Gyrotron
B
Travelling wave tube
C
Magnetron
D
Relfex klystron
Which of the devices has the negative resistance characteristic? A
PNP transistor
B
Magnetron
C
Reflex klystron
D
Gunn diode
Which of the following devices is a not electron diode? A
Thermal electron diode
B
Thomson deletion diode
C
Thermionic tube diode
D
Schottky barrier diode
Which of the following uses transferred electron effect for the production of microwave power amplifier? A Metal semi conductor B Germanium C
119
D
Consider the following statements: The klystron and travelling wave tube differ from each other 1. in TWT the microwave circuit is non resonant . 2. in klystron the microwave circuit is resonant . 3. TWT uses attenuator . 4. the wave in TWT is a non proper gating wave . which of the above statements are correct? A 2 and 3 B 1 C
115
filter
Silicon
D
Gallium arsenide
Which of the following is a microwave power amplifier? A
Magnetron
B
Travelling wave tube
C
Gunn diode
D
Reflex klystron
The frequency determining portion of a magnetron is______ A
short line
B
cathode
C
open line
D
Reasonant cavity
MASER finds application in A
telephones
B
fiber optics
C
opto electronics
D
all the above
122
Consider the following statements: In the case of space wave propagation the signal strength at the receiver is 1.directly proportional to transmitter and receiver heights 2.inversely proportional to distance between transmitter and receiver 3.directly proportional to frequency Which of the above statements are correct? A 3 B 2 C
123
124
125
1 and 3
D
1
Which of the following frequency bands fall under microwave frequency? A
SHF and EHF
B
UHF
C
UHF and SHF
D
SHF and EHF
The gain of a TWT is proportional to_____ A
type of input and output
B
length of tube
C
no both A and B
D
none of the these
Large microwave power may be measured with the help of A
Calorimeter
B
thermister
C
Bolometer
D
barreter
126
Microwave circuit impedance or admittance can be determined from readings of A Maximum and minimum B VSWR values of crystal current C Both (A) and (B) above D None of the above
127
Most of the power measuring microwave devices measure
128
A
Average power
B
Peak power
C
Instantaneous power
D
None of the above
The most fundamental method of frequency measurement is A C
129
With an absorption wave meter With a slotted line
B
With a slotted line
D
By comparison
In laboratory experiments the output from the Reflex Klystron are modulated by square wave because A It is easy to generate a B Crystal diode operates in the square wave square law region of the V-I characteristic C It prevents frequency D Detector circuit is less modulation complicated.
130
In order to couple two generators to a waveguide system without coupling them to each other, one could not use A Rat-race B E-plane T C
131
134
D
Magic T
B
An inter metallic compound with particularly good conductivity A microwave semiconductor invented by Faraday
A ferrite is A
132
Hybrid ring
A non-conductor with magnetic properties
C
An insulator which heavily attenuates magnetic fields A PIN diode is
D
A
B
A microwave mixer diode
D
Suitable for use as a microwave switch.
A metal semiconductor point-contact diode C Often used as a microwave detector A duplexer is used to A
135
Couple two different B Allow the one antenna to be antennas to a transmitter used for reception or without mutual transmission without mutual interference interference C To prevent interference D To increase the speed of the between two antennas pulses in pulsed radar when they are connected to a receiver For low attenuation, the best transmission medium is A C
136
138
Rectangular waveguide
B
Ridge waveguide
D
Coaxial line
A microwave tube amplifier uses an axial magnetic field and a radial electric field. This is the A Reflex klystron B Coaxial magnetron C
137
Flexible waveguide
Travelling wave tube
D
CFA
One of the reason why vacuum tubes eventually fail at microwave frequencies is that their A Noise figure increases B Transit time becomes too short C Shunt capacitive D Series inductive reactance reactance become too become too small large Te cavity magnetron uses strapping to
139
A
Prevent mode jumping
B
C
Ensure bunching
D
Prevent cathode back heating
Improve the phase focusing effect A magnetic field is used in the cavity magnetron to A
140
Prevent anode current in B Ensure that the oscillation are the absence of oscillations pulsed C Help in focusing the D Ensure that the electrons will electron beam, thus orbit around the cathode. preventing spreading The primary purpose of the helix in a travelling wave tube is to A
141
142
Prevent the electron B Reduce the axial velocity of beam from spreading in the RF field the long tube C Ensure broad band D Reduce the noise figure. operation A backward wave oscillator is based on the A
Rising sun magnetron
B
Cross Field Amplifier
C
Coaxial magnetron
D
Travelling wave tube
A Parametric amplifier must be cooled A
143
Because parametric B amplification generates lots of heat C Because it cannot operate D at room temperature A ruby maser amplifier must be cooled
To increase bandwidth
To improve the noise performance
A
144
Because maser B To increase bandwidth amplification generates lots of heat C Because it cannot operate D To improve the noise at room temperature performance A Disadvantage of micro strip compared with strip line is that micro strip A
145
B
C
Does not readily land itself to printed circuit techniques Is bulkier
Is more likely to radiate
A
Micro strip
B
Electrical wave guide
C
Parallel wire Line
D
Strip Line
D
Is more expansive and complex to manufacture The Transmission system using two ground plane is
146
147
Surface acoustic waves propagates in A
Gallium Arsenide
B
Indium Phosphide
C
Strip Line
D
Quartz Crystal
B
Filters
C
Transmission media like Strip Line UHF Amplifiers
A
Lower Noise
B
Saw Devices may be used as A
148
D
Oscillator as millimetre Frequencies The biggest advantage of the TRAPATT Diode over the IMPATT Diode is its Higher Efficiency
C 149
Ability to operate at D Lesser Sensitivity to higher Frequencies Harmonics Indicate which of the following Diodes will Produce highest Pulse Power Output A Varactor B Gunn C
150
RIMPATT
IMPATT
D
Tunnel
One of the following microwave diode is suitable for Very low power oscillators Only A Tunnel B Avalanche C
152
D
Indicate which of the following Diodes does not use negative resistance in its operation A Backward B Gunn C
151
SCHOTTKY Barrier
Gunn
D
IMPATT
A Parametric Amplifier has an Input and Output Frequency of 2.25GHZ,and its pump at 4.5GHz.It is a A Travelling wave amplifier B Generative Amplifier C
153
Lower Sideband UpD Upper Sideband Up-Converter Converter A non degenerate a Parametric Amplifier has an input Frequency fi and a Pump Frequency fp. The idler frequency is A fi B 2fi C
154
fi – fp
D
fp – fi
A Tunnel diode is loosely couple to its cavity in order to A
Increase the Frequency Stability
B
Increase the Available negative resistance
C 155
D
Allow Operation at highest frequency
The Negative resistance in a Tunnel Diode A
156
Facilitate Tuning
Is maximum at the peak B point of the characteristics Is maximum at valid point D
Is available between the peak and valid points C Maybe improved by reverse bias Negative Resistance is obtained with a Gunn Diode because of A
157
158
159
160
Electron Transfer to a less B Avalanche breakdown with mobile energy level the high voltage gradient C Tunnelling across the D Electron domains forming at junction the junctions For Gunn Diodes, Gallium Arsenide is Preferred to Silicon because the former A Has a suitable empty B Has a higher ion mobility energy band, which silicon does not have C Has a lower noise at a D Is capable of handling higher highest Frequencies power densities. The Ruby laser differs from the Ruby maser in that the former A
Does not require pumping
B
Need no resonator
C
Is an Oscillator
D
Produces much more powers
The output from a laser is monochromatic : This means that it is A
Infrared
B
Polarised
C
Narrow beam
D
Single Frequency
If the peak transmitted power in the radar system increases why a factor of 16,maximum range will be increased by a factor of A 2 B 4 C
161
D
16
If the antenna diameter in a radar system is increase by factor of 4,the maximum range will be increased by a factor of A √2 B 2 C
162
8
4
D
8
The Radar cross section of a target (indicate the false statement) A C
Depends on the frequency used Depends on the aspect of a target, if this is non spherical
B D
Maybe reduced by the special coating of the target Is equal to the actual cross sectional area for small targets
163
164
The If bandwidth of a radar receiver is inversely proportional to the A
Pulse width
B
C
Pulse interval
D
Pulse repetition frequency
Square root of the peak transmitted power The biggest disadvantage of CW Doppler radar is that A
165
Is does not give the target B Is does not give the target velocity range C A transponder is required D Is does not give the target at target position A solution to the “Blind Speed” Problem is to A C
166
167
168
169
170
B
Vary the PRF
D
Use MTI
The standard reference antenna for the directive gain is the A
Infinitesimal dipole
B
Isotropic antenna
C
Elementary doublet
D
Half wave dipole
Top loading is some time used with an antenna in order to increase its A
Effective height
B
Bandwidth
C
Beam width
D
Input Capacitance
A helical antenna is used for satellite tracking because of its A
Circular Polarisation
B
Maneuverability
C
Broad bandwidth
D
Good front to back ratio
When the free space wavelength of a signal equal the cut off wavelength of the guide (Indicate the false statement) A Group velocity of the B Phase velocity of the signals signal become zero becomes infinite C Characteristics impedance D The wavelength within the of the guide becomes waveguide become infinite infinite A Signal Propagated in a waveguide has a full wave of electric intensity change between the two further walls, and no components of the electric filed in the direction of the propagation. The mode is A TE1,1 B TE1,0 C
171
Change the Doppler frequency Use mono pulse
TM2,2
D
TE2,0
The square of the periodic time orbit is proportional to the cube of the mean distance between the two bodies is the statement of
172
173
A
Kepler’s first law
B
Kepler’s second law
C
Kepler’s third law
D
None of the above
Dielectric lens act as A
Directive antennas
B
Non-directive antennas
C
Diploes
D
Monopoles
If the mouth diameter of a parabolic antenna is 2.5m and if it is operating at frequency of 10 GHz, the power gain in dB is A 46.19 B 25 C
174
175
176
177
179
100
A
10
B
100
C
1000
D
1
A magnetic dipole is A
A small circular loop
B
A piece of wire
C
A piece of conducting rod
D
The same as electric dipole
The normalised radiated power of a dipole is A
1
B
1.5
C
sin2Ѳ
D
1.64
The resonant frequency of a rectangular cavity of dimensions a= 3 cm, b=2cm, d=4cm and operating in TE101 Mode is A 6 GHz B 6.25GHz 6.5GHz
D
6.75GHz
A directional coupler is a _________ Port Device. A
1
B
2
C
3
D
4
The match load absorbs _______ incident Power upon it and reflects _______. A NO,NO B NO,YES C
180
D
The maximum gain of 100 element uniform linear array is
C 178
250
YES,NO
D
YES,YES
B
Radio detection and range
The term radar is an acronym for A
Raster direction and ranging
C 181
Radio direction and range
C
Both the amplitude & phase phase
182
B
Amplitude
D
None of these
IMPATT device has ____layers in order A
p.n.i,p
B
n+,p,i,p+
C
n+,p,i,n+
D
P+.n.i,p+
Step recovery diode (select the correct statement) A
Made of Si or GaAs
B
C 184
Stores the charge under D forward bias condition Applications of Varactor diodes are A C
185
Range detection of radio wave
Coherent pulse Doppler radars measures_____ of radar echoes A
183
D
Widely used in parametric amplifier Active filter
Also known as Snap-off varactor diode All of these
B
Harmonic generator
D
All of these
Which of the following microwave component has got the combined characteristic of dielectric, ohmic and radiation losses? A Wave guide B Micro strip line C
Coaxial line
D
Two wire parallel line
Q: 1
Which of the following is the binary representation of F03516 hexadecimal number? A 1111000000110111 B 1111000001110101 C
Q: 2
Q: 5
Q: 6
Q: 7
Q:8
1111100000110101
2B
D
2A
Which of the following is the decimal representation of 6B216 hexadecimal number? A 1512 B 1714 C
Q: 4
D
Which of the following is the hexadecimal representation of 4510 (decimal number)? A 2D B 2C C
Q: 3
1111000000110101
1514
D
1614
Perform hex subtraction of 59F – 2B8 and the answer is _____. A
2E7
B
2E9
C
2C7
D
2B7
Find 2’s complement of 1001010 and the answer is _____. A
0110110
B
0110111
C
0111110
D
0110101
M = 1010100 and N = 1000100, M – N = _______. A
10000
B
110000
C
100000
D
10001
M = 1000100 and N = 1010100, M – N = _______. A
1101111
B
-10000
C
-1101111
D
10000
The binary conversion of (0.6875)10 is _______. A
0.0001
B
0.0101
C
0.1011
D
0.1110
Q:9
Q: 10
Q: 11
Q: 12
Q: 13
Q: 14
Q:15
Q:16
(41.6875)10 = __________________ A
(101001.1010)2
B
(101001.1011)2
C
(101000.1011)2
D
(101000.1011)2
(153.513)10 = __________________ A
(231.416517)8
B
(230.406517)8
C
(221.406517)8
D
(231.406517)8
(10110001101011.111100000110)2 = ________________ A
(26153.7416)8
B
(26163.7406)8
C
(26143.7406)8
D
(26153.7406)8
(10110001101011.11110010)2 = __________________ A
(2C6B.F2)16
B
(2C6B.F1)16
C
(2D6B.F2)16
D
(2C6A.F2)16
(306.D)16 = _________________ A
(001100000110.1100)2
B
(001100000111.1101)2
C
(001100000110.1101)2
D
(011100000110.1100)2
(673.124)8 = ________________ A
(110111011.001010100)2
B
(110111001.001010101)2
C
(110111011.001010101)2
D
(110111111.001010100)2
(11010011)2 + (1101111)2 = ____________ A
(001000010)2
B
(101000010)2
C
(101010010)2
D
(101000011)2
24 kilobytes = _________ bytes A
24576
B
24000
C
24600
D
24500
Q: 17
Q: 18
ROM memory address map of AT89C51 with 4 KB of ROM is ________ A
0000 to 1FFFH
B
0000 to 0FFFH
C
0000 to 2FFFH
D
0000 to FFFFH
ROM memory address map of DS89C420 with 16 KB of ROM is ________ A 0000 to 1FFFH B 0000 to 3FFFH C
Q: 19
Q: 23
Q: 24
0000 to 6FFFH
D
0000 to 8FFFH
CY =1, AC = 1, P = 1
D
CY =1, AC = 0, P = 0
What is the content of PSW register after the execution following instructions in the program for 8051 Microcontroller? MOV A, #0BFH ADD A, #1BH A 40H B 00H C
Q: 22
0000 to 4FFFH
What is the status of the CY, AC, and P flags after the execution following instructions in the program for 8051 Microcontroller? MOV A, #9CH ADD A, #64H A CY =1, AC = 1, P = 0 B CY =0, AC = 1, P = 0 C
Q: 21
D
ROM memory address map of DS5000-32 with 32 KB of ROM is ________ A 0000 to FFFFH B 0000 to 7FFFH C
Q: 20
0000 to 2FFFH
41H
D
01H
Which of the following instruction can be used to select register bank3 in 8051 microcontroller? A CLR PSW.4 B SETB PSW.4 SETB PSW.3 SETB PSW.3 C CLR PSW.3 D SETB PSW.3 CLR PSW.4 CLR PSW.4 Which bits of the PSW of 8051microcontroller are user-definable? A
PSW.4 and PSW.5
B
PSW.4 and PSW.3
C
PSW.1 and PSW.3
D
PSW.1 and PSW.5
In 8051 microcontroller, the program counter is _____ bits wide. A
12
B
8
C
20
D
16
Q: 25
Q: 26
Q: 27
Q: 28
Q: 29
________ is the number of I/O pins in 8051 microcontroller. A
30
B
32
C
40
D
24
________ number of timers are available in 8051 microcontroller. A
1
B
3
C
2
D
4
________ on-chip ROM is available in 8031 microcontroller. A
4K
B
8K
C
16 K
D
0K
The size of stack pointer register in 8051 microcontroller is _______. A
4 bits
B
8 bits
C
12 bits
D
16 bits
In 8051 microcontroller, with the execution of each PUSH instruction, stack pointer register is ___________. A Incremented by 1 B Decremented by 1 C
Q: 30
Decremented by 2
Incremented by 2
D
Decremented by 2
In 8051, on power-up, SP = _____ and the first RAM location used as a stack ______. A 7, 8 B 7, 6 C
Q: 32
D
In 8051 microcontroller, with the execution of each POP instruction, stack pointer register is ___________. A Incremented by 1 B Decremented by 1 C
Q: 31
Incremented by 2
8, 7
D
6, 7
In 8051, initially, the program counter is ______ when powered-up. A
0001H
B
1000H
C
0000H
D
FFFFH
Q: 33
In 8051, the target address in SJMP instruction is within _____ to _____ bytes of memory location from the current address of program counter. A -127 to 128 B -128 to 127 C
Q: 34
Q: 35
Q: 36
Q: 37
Q: 38
0 to 127
A
1
B
4
C
3
D
2
On execution of LCALL instruction in 8051, SP is _______. A
Incremented by 2
B
Incremented by 1
C
Decremented by 2
D
Decremented by 1
On execution of RET instruction in 8051, SP is _______. A
Incremented by 2
B
Incremented by 1
C
Decremented by 2
D
Decremented by 1
In 8051, ACALL is _______ instruction. A
2 bytes
B
3 bytes
C
1 byte
D
4 bytes
For an 8051 system of 11.0592 MHz, how long it takes to execute one machine cycle instruction? (Take 1 machine cycle = 12 clock periods) A 10.85 µs B 0.1085 µs 1.085 µs
D
108.5 µs
_____ and _____ ports provide address when 64 K bytes of external memory is interfaced with 8031. A P0 and P2 B P0 and P1 C
Q: 40
D
In 8051, LJMP (long jump) is ____ byte/s instruction.
C Q: 39
0 to 256
P1 and P3
D
P1 and P2
Which 8051 port/s need pull-up resistors to function as I/O port? A
P0 and P1
B
P0
C
P1 and P2
D
P1
Q: 41
In 8051, _____ and _____ pins port 3 can be used as RxD and TxD, respectively. A P3.0, P3.1 B P3.2 and P3.3 C
Q: 42
To copy C to P2.4
D
To copy CY to P2.4
MOV A, #25H
D
MOV A, 4
MOV A, #25H
D
MOV A, 4
MOV A, #25H
D
MOV A, 4
In 8051, which of the following instruction can be said to represent register indirect addressing mode? A MOV A, R0 B MOV A, @R0 C
Q: 48
Input or output
In 8051, which of the following instruction can be said to represent direct addressing mode? A MOV A, R0 B MOV A, @R0 C
Q: 47
D
In 8051, which of the following instruction can be said to represent register addressing mode? A MOV A, R0 B MOV A, @R0 C
Q: 46
Neither input nor output
In 8051, which of the following instruction can be said to represent immediate addressing mode? A MOV A, R0 B MOV A, @R0 C
Q: 45
P3.3 and P3.2
The function of following instruction in 8051 is _______. MOV C, P2.4 A Incorrect instruction B To copy status of P2.4 to CY C
Q: 44
D
In 8051, the instruction – JNB P2.5, HERE, assumes that bit P2.5 is an ______. A Output B Input C
Q: 43
P3.1, P3.0
MOV A, #25H
D
MOV A, 4
In 8051, the meaning of MOV A, 7 is ________. A
To copy R7 into A
B
Incorrect instruction
C
To load A with value 7
D
None of the above
Q: 49
In 8051, the meaning of MOV @R1, B is ________. A
Q: 50
Copy contents of B into B Incorrect instruction RAM location whose address is held by R1 C Copy contents of R1 into D Copy B into R1 RAM location whose address is held by B In 8051, which of the following instruction can be said to represent indexed addressing mode? A MOV A, R0 B MOV A, @R0 C
Q: 51
Q: 52
Q: 53
Q: 54
Q: 55
D
MOVC A, @A+DPTR
In 8051, the instruction MOV A, 40H uses __________ addressing mode. A
Immediate
B
Register
C
Register indirect
D
Direct
In 8051, the instruction MOV A, #40H uses __________ addressing mode. A
Immediate
B
Register
C
Register indirect
D
Direct
In 8051, the instruction MOV A, R0 uses __________ addressing mode. A
Immediate
B
Register
C
Register indirect
D
Direct
In 8051, the instruction MOV A, @R0 uses __________ addressing mode. A
Immediate
B
Register
C
Register indirect
D
Direct
In 8051, out of 128 byte internal RAM, how many byte locations are bitaddressable? A 128 B 16 C
Q: 56
MOV A, #25H
64
D
32
In 8051, which of the following instruction sets bit P0.6? A
SETB 81H
B
SETB 80H
C
SETB 82H
D
SETB 86H
Q: 57
Q: 58
A
B
C
D
In which language, program are written in mnemonics? A
Assembly language
B
Machine language
C
High-level language
D
None of the above
In 8085, instruction OUT 01H does ___________ on execution. A
Q: 59
Displays program counter B Displays accumulator content content at port 01H at port 01H C Displays register B content D Displays register C content at at port 01H port 01H In 8085, instruction ADD M does ___________ on execution. A
Q: 60
Add the content of A with B Add the content of A with that that of memory location of memory location pointed pointed by HL register by BC register pair pair C Add the content of B with D Add the content of A with that that of memory location of memory location pointed pointed by HL register by DE register pair pair In 8085, instruction XRI 6AH does ___________on execution. A
Q: 61
Exclusive-OR 6AH with B Exclusive-OR 6AH with the the contents of B contents of A C Exclusive-OR 6AH with D Exclusive-OR 6AH with the the contents of C contents of D In 8085, instruction JC 2025H does ___________on execution. A
Q: 62
Change the program B Incorrect instruction sequence to 2025H if the carry flag is reset C Change the program D Change the stack pointer data sequence to 2025H if the to 2025H if the carry flag is set carry flag is set In 8085, instruction ANA M does ___________ on execution. A
C
Logically AND the contents of accumulator with that of memory location pointed by HL register pair Logically AND the contents of register B with
B
Logically AND the contents of accumulator with that of memory location pointed by BC register pair
D
Incorrect instruction
Q: 63
that of memory location pointed by HL register pair In 8085, instruction CPI 4FH does ___________on execution. A C
Compare 4FH with the contents of B Compare 4FH with the contents of C
B D
Compare 4FH with the contents of A Incorrect instruction
Q: 64
In 8085, instruction SUI 7FH does ___________ on execution. A
Q: 65
Subtract 7FH from the B Subtract 7FH from the contents of A contents of B C Subtract A from the D Subtract B from the contents contents of 7FH of 7FH In 8085, instruction MOV B, M does ___________ on execution. A
Q: 66
Copy the content of B Incorrect instruction memory location pointed by DE register into B C Copy the content of D Copy the content register B memory location pointed into the memory location by HL register into B pointed by HL register In 8085, instruction DCX B does _____________ on execution. A
Decrement the content of register pair B
B
C Q: 67
Decrement the content of D register B In 8085, instruction SUB M does _____________ on execution. A
Q: 68
Q: 69
Q: 70
Subtract the content of memory location pointed by BC register pair from accumulator C Subtract the content of memory location pointed by DE register pair from accumulator 8085 is _____ microprocessor.
B
D
Subtract the content of memory location pointed by HL register pair from accumulator Incorrect instruction
A
8-bit
B
16-bit
C
20-bit
D
10-bit
Which one of the following is valid register pair in 8085 microprocessor? A
HD
B
BC
C
HE
D
BH
In 8085, ____________ address lines are multiplexed with data lines. A
Q: 71
Decrement the content of memory location pointed by register pair B Incorrect instruction
Higher-order eight address B Higher-order four address lines lines C Lower-order four address D Lower-order eight address lines lines In 8085, ______________ control signal is used to de-multiplex address lines from data lines.
A
ALE
B
S0
C
INTR
D
S1
Q: 72
Q: 73
Q: 74
Q: 75
Q: 76
Q: 77
Q: 78
Q: 79
In 8085, what should be status of S1 and S0 for opcode fetch operation? A
S1 = 1 and S0 = 1
B
S1 = 0 and S0 = 0
C
S1 = 1 and S0 = 0
D
S1 = 0 and S0 = 1
In 8085, what should be status of S1 and S0 for memory read operation? A
S1 = 1 and S0 = 1
B
S1 = 0 and S0 = 0
C
S1 = 1 and S0 = 0
D
S1 = 0 and S0 = 1
In 8085, what should be status of S1 and S0 for memory write operation? A
S1 = 1 and S0 = 1
B
S1 = 0 and S0 = 0
C
S1 = 1 and S0 = 0
D
S1 = 0 and S0 = 1
In 8085, what should be status of S1 and S0 for I/O read operation? A
S1 = 1, S0 = 1, IO / M = 1 B
S1 = 0, S0 = 0, IO / M = 1
C
S1 = 1, S0 = 0, IO / M = 1 D
S1 = 0, S0 = 1, IO / M = 1
In 8085, what should be status of S1 and S0 for I/O write operation? A
S1 = 1, S0 = 1, IO / M = 1
B
S1 = 0, S0 = 0, IO / M = 1
C
S1 = 1, S0 = 0, IO / M = 1 D
S1 = 0, S0 = 1, IO / M = 1
Which of the following interrupt has highest priority in 8085? A
TRAP
B
RST 7.5
C
RST 5.5
D
RST 6.5
Which of the following is vectored interrupt in 8085? A
HLDA
B
HOLD
C
RST 7.5
D
INTR
Which of the following signal/pin is used to interface slow-responding peripheral with 8085 microprocessor? A HOLD B READY C
RST 7.5
D
INTR
Q: 80
Q: 81
In 8085, MOV C, A instruction is executed in _________ T-states _________ machine cycles. A 7 T-states and 2 machine B 10 T-states and 3 machine cycles cycles C 4 T-states and 1 machine D 13 T-states and 4 machine cycle cycle AC flag in 8085 is set in arithmetic operation when ___________. A
Q: 82
Q: 83
Q: 84
Q: 85
Carry is generated from D3 B Carry is generated from D7 and and passed on to D4 passed on to D0 C Carry is generated from D4 D Carry is generated from D6 and and passed on to D5 passed on to D7 In 8085, MVI A, 32H instruction is executed in _________ T-states _________ machine cycles. A 7 T-states and 2 machine B 10 T-states and 3 machine cycles cycles C 4 T-states and 1 machine D 13 T-states and 4 machine cycle cycle S flag in 8085 is set in arithmetic/logical operation when ___________. A
D6 comes out be 1
B
D7 comes out be 0
C
D6 comes out be 0
D
D7 comes out be 1
Z flag in 8085 is set when ALU operation results in ___________. A
00H
B
AAH
C
11H
D
FFH
P flag in 8085 is set when arithmetic/logical operation results in ___________. A Even number of 1s B Odd number of 1s C
Q: 86
Q: 87
D7 comes out be 1
D
D7 comes out be 0
In 8085, the instruction IN 84H requires __________ T-states and _________ machine cycles. A 7 T-states and 2 machine B 10 T-states and 3 machine cycles cycles C 4 T-states and 1 machine D 13 T-states and 4 machine cycle cycle Absolute address decoding technique results into _______ address/es for each peripheral interfaced microprocessor/microcontroller. A Unique B Multiple C
Infinite
D
Three
Q: 88
Partial address decoding technique results into _______ address/es for each peripheral interfaced microprocessor/microcontroller. A Unique B Multiple C
Q: 89
D
10
12
D
10
MOV M, B
D
STA
In memory-mapped I/O interfacing technique in 8085, which of the following instruction can be used? A IN B OUT C
Q: 93
12
In peripheral I/O interfacing technique in 8085, which of the following instruction can be used? A IN B LDA C
Q: 92
None of the above
In memory-mapped I/O interfacing technique in 8085, ________ address pins can be used at most to generate address for peripheral/memory. A 8 B 16 C
Q: 91
D
In peripheral I/O interfacing technique in 8085, ________ address pins can be used at most to generate address for peripheral. A 8 B 16 C
Q: 90
Infinite
STA
D
None of the above
In 8085, which interfacing technique permits arithmetic and logical operations directly to be performed on data? A Peripheral I/O B Memory-mapped I/O C
Q: 94
Peripheral and memoryD None of the above mapped I/O In peripheral I/O interfacing technique in 8085, _____ input and _____ output devices can be connected at most. A 255, 256 B 256, 255 C
Q: 95
256, 256
D
255, 255
In memory-mapped I/O interfacing technique in 8085, __________. A C
Memory map is shared between I/Os and memory Memory map is 0 to 64K
B D
I/O map is independent of memory I/O map is 0 to 256
Q: 96
Q: 97
Q: 98
HLT instruction in 8085 is ________ byte instruction. A
One
B
Two
C
Four
D
Three
NOP instruction in 8085 is ________ byte instruction. A
One
B
Two
C
Four
D
Three
Which of the following statement can be said to be of the kind of indirect addressing mode? A Pass the butter B Pass the bowl C
Q: 99
Give me item no. 17 of D I will have what Manish has menu In 8085, if accumulator has FFH, carry flag (CY) equal to 0 and now, INR A instruction is executed, which of the following is true? A S = 0, Z = 1, CY =1 B S = 1, Z = 1, CY =1 C
S = 0, Z = 1, CY =0
D
S = 1, Z = 1, CY =0
Q:100 In 8085, if accumulator has FFH, carry flag (CY) equal to 0 and now, ADI 01H instruction is executed, which of the following is true? A S = 0, Z = 1, CY =1 B S = 1, Z = 1, CY =1 C
S = 0, Z = 1, CY =0
D
S = 1, Z = 1, CY =0
Q:101 In 8085, what is the position of carry flag in flag register? A
D7
B
D6
C
D4
D
D0
Q:102 In 8085, what is the position of sign flag in flag register? A
D7
B
D6
C
D4
D
D0
Q:103 In 8085, what is the position of zero flag in flag register? A
D7
B
D6
C
D4
D
D0
Q:104 In 8085, what is the position of auxiliary carry flag in flag register? A
D7
B
D6
C
D4
D
D0
Q:105 In 8085, what is the position of parity flag in flag register? A
D2
B
D6
C
D4
D
D0
Q:106 Which of the following statement can be said to be of the kind of direct addressing mode? A Pass the butter B Pass the bowl C
Give me item no. 17 of D I will have what Manish has menu Q:107 Which of the following program can display FFH data on a port with address 01H for 8085? A MVI C, FFH B MVI B, FFH OUT 01H OUT 01H HLT HLT C MVI D, FFH D MVI A, FFH OUT 01H OUT 01H HLT HLT Q:108 The result of XRA A instruction for 8085 is _________. A
00H
B
FFH
C
55H
D
Incorrect instruction
Q:109 Which logical operation is generally used to mask certain bits of accumulator? A And operation B Or operation C
NOT operation
D
XOR operation
Q:110 Which logical operation is generally used to set certain bits of accumulator? A And operation B Or operation C
NOT operation
D
XOR operation
Q:111 LXI H, 2050H instruction of 8085 does on execution _________. A
H = 50H, L = 20H
B
Incorrect instruction
C
H = 20H, L = 50H
D
Data from 2050 H memory location with copied to A
Q:112 LDAX B instruction of 8085 does on execution _________. A
Incorrect instruction
B
C
Data from memory location pointed by DE pair copied to A Data from register pair BC copied to A
Data from memory D location pointed by BC register pair copied to A Q:113 LDAX D instruction of 8085 does on execution _________. A
Incorrect instruction
B
C
Data from memory location pointed by DE pair copied to A Data from register pair DE copied to A
Data from memory D location pointed by DE register pair copied to A Q:114 STAX B instruction of 8085 does on execution _________. A
Incorrect instruction
B
C
Data from memory location pointed by DE pair copied to A Data from A copied into register pair BC
Data from A copied into D memory location pointed by BC register pair Q:115 STAX D instruction of 8085 does on execution _________. A
Incorrect instruction
B
C
Data from memory location pointed by DE pair copied to A Data from A copied into register pair DE
Data from A copied into D memory location pointed by DE register pair Q:116 For 8085, if A = 55H and CY = 1, which of the following is true on execution of RLC instruction? A D0 = 0, D7 = 1, CY = 0 B D0 = 1, D7 = 1, CY = 0 C
D0 = 0, D7 = 1, CY = 1
D
D0 = 1, D7 = 1, CY = 1
Q:117 For 8085, if A = 55H and CY = 1, which of the following is true on execution of RAL instruction? A D0 = 0, D7 = 1, CY = 0 B D0 = 1, D7 = 1, CY = 0 C
D0 = 0, D7 = 1, CY = 1
D
D0 = 1, D7 = 1, CY = 1
Q:118 For 8085, if A = 55H and CY = 1, which of the following is true on execution of RRC instruction? A D0 = 0, D7 = 1, CY = 0 B D0 = 1, D7 = 1, CY = 0 C
D0 = 0, D7 = 1, CY = 1
D
D0 = 1, D7 = 1, CY = 1
Q:119 For 8085, if A = 55H and CY = 1, which of the following is true on execution of RAR instruction? A D0 = 0, D7 = 1, CY = 0 B D0 = 1, D7 = 1, CY = 0 C
D0 = 0, D7 = 1, CY = 1
D
D0 = 1, D7 = 1, CY = 1
Q:120 In 8085, if data of accumulator and register B are same, on execution of CMP B instruction results into __________. A Z flag set, CY flag reset B Z flag set, CY flag set C
Z flag reset, CY flag set
D
Z flag reset, CY flag reset
Q:121 In 8085, if data of accumulator greater than that of register B, on execution of CMP B instruction results into __________. A Z flag set, CY flag reset B Z flag set, CY flag set C
Z flag reset, CY flag set
D
Z flag reset, CY flag reset
Q:122 In 8085, if data of accumulator greater than that of register B, on execution of CMP B instruction results into __________. A Z flag set, CY flag reset B Z flag set, CY flag set C
Z flag reset, CY flag set
D
Z flag reset, CY flag reset
Q:123 In 8085, instruction ANI 01H masks ________ bits. A
D7 to D0
B
D7 to D1
C
D0
D
D1
Q:124 In 8085, instruction ANI 00H masks ________ bits. A
D7 to D0
B
D7 to D1
C
D0
D
None of the bits
Q:125 In 8085, on execution of PUSH B instruction, SP is _________. A
Decremented by 2
B
Decremented by 1
C
Incremented by 2
D
Incremented by 1
Q:126 In 8085, on execution of POP B instruction, SP is _________. A
Decremented by 2
B
Decremented by 1
C
Incremented by 2
D
Incremented by 1
Q:127 In 8085, on execution of POP PSW instruction, SP is _________. A
Decremented by 2
B
Decremented by 1
C
Incremented by 2
D
Incorrect instruction
Q:128 In 8085, if H = 20H and L = 50H, and execution of PUSH H is followed with POP PSW. Which of the following is true in this case? A A = 50H, Flag register = B A = 20H, Flag register 20H maintain previous state and not affected C A = 20H, Flag register = D Accumulator and Flag 50H registers maintain previous state and not affected Q:129 In 8085, on execution of CALL instruction, SP is _______. A
Decremented by 2
B
Decremented by 1
C
Incremented by 2
D
Incremented by 1
Q:130 In 8085, on execution of RET instruction, SP is _______. A
Decremented by 2
B
Decremented by 1
C
Incremented by 2
D
Incremented by 1
Q:131 In 8085, the meaning CNC is __________. A
Incorrect instruction
B
Call subroutine if CY = 1
C
Call subroutine if CY = 0
D
Call subroutine unconditionally
Q:132 In 8085, the meaning CM is __________. A
Incorrect instruction
B
Call subroutine if S = 1
C
Call subroutine if S = 0
D
Call subroutine unconditionally
Q:133 In 8085, the meaning CP is __________. A
Incorrect instruction
B
C
Call subroutine if S = 0
D
C
AC
D
Call subroutine if S = 1
Call subroutine unconditionally Q:134 In 8085, DAA instruction uses _____ and _____ flags to perform decimal adjustment of accumulator. A CY, AC B CY CY, S
Q:135 In 8085, LHLD 2050H instruction does _______ on execution. A
C
Loads data from memory location 2050H to L and 2051H to H Loads data from memory location 2050H to H and 2051H to L
B
Copies L with 50H and H with 20H
D
Copies H with 50H and L with 20H
Q:136 In 8085, SHLD 2050H instruction does _______ on execution. A
Stores data of H into B Copies L with 50H and H with memory location 2050H 20H and L into 2051H C Stores data of L into D Copies H with 50H and L with memory location 2050H 20H and H into 2051H Q:137 In 8085, XCHG instruction does _______ on execution. A
Content of HL and DE B Content of H and D registers register pairs exchanged exchanged C Content of HL and BC D Content of L and E registers register pairs exchanged exchanged Q:138 In 8085, ADC B instruction does _______ on execution. A
A = A + B + CY flag
B
B = A + B + CY flag
C
A=A+B
D
B=A+B
Q:139 In 8085, if HL register pair is cleared, DAD SP instruction does _______ on execution. A Clears SP B Places the content of SP in DE C
Places the content of SP in D Places the content of SP in BC HL Q:140 In 8085, instruction XTHL does _________ execution. A
Contents of L exchanged B Contents of L exchanged with with memory location memory location pointed by pointed by SP and H with SP memory location pointed by SP + 1. C Contents of H exchanged D Contents of H exchanged with with memory location memory location pointed by pointed by SP and L with SP memory location pointed by SP + 1. Q:141 Which instruction in 8085 is used to complement carry flag? A
CMA
B
STC
C
CMC
D
None of the above
Q:142 Which instruction, in 8085, is used to set carry flag? A
CMA
B
STC
C
CMC
D
None of the above
Q:143 Which instruction, in 8085, is used to copy H and L registers in the program counter?
A
SPHL
B
PCHL
C
XCHG
D
None of the above
Q:144 Which instruction, in 8085, is used to copy H and L registers in the program counter? A SPHL B PCHL C
XCHG
D
None of the above
Q:145 Which instruction, in 8085, is used to enable interrupt? A
EI
B
DI
C
RIM
D
None of the above
Q:146 Which instruction, in 8085, is used to disable interrupt? A
EI
B
DI
C
RIM
D
None of the above
Q:147 Which instruction, in 8085, is used to read pending interrupt requests? A
EI
B
DI
C
RIM
D
None of the above
Q:148 What is the use of SIM instruction in 8085? A C
To enable/disable RST 7.5, 6.5, 5.5 To enable TRAP
B D
To read pending interrupt requests To enable INTR interrupt
Q:149 What is the use of 8259A? A
Programmable keyboard/display interface C Programmable interrupt controller Q:150 What is the use of 8279? A
Programmable keyboard/display interface C Programmable interrupt controller Q:151 What is the use of 8155? A C
Programmable keyboard/display interface Programmable interrupt controller
B D
B D
B D
Programmable I/O ports and timer Direct memory access controller Programmable I/O ports and timer Direct memory access controller Programmable I/O ports and timer Direct memory access controller
Q:152 What is the use of 8237? A
Programmable keyboard/display interface C Programmable interrupt controller Q:153 What is the use of 8255A? A
Programmable keyboard/display interface C Programmable interrupt controller Q:154 What is the use of 8253?
B D
B D
Programmable I/O ports and timer Direct memory access controller Programmable peripheral interface Direct memory access controller
A
Programmable B Programmable interval timer keyboard/display interface C Programmable interrupt D Direct memory access controller controller Q:155 Which port in 8255A can be used as individual pins or grouped in two 4bit ports? A Port A B Port B C
Port A and Port B
D
Port C
Q:156 Which instruction, in 8085, is used to output data serially through SOD line? A SIM B RIM C
DI
D
EI
Q:157 Which instruction, in 8085, is used to input data serially through SOD line? A SIM B RIM C
DI
D
EI
Q:158 8086 is _______ bits microprocessor. A
8
B
16
C
10
D
20
Q:159 The memory addressing capacity of 8086 is ________. A
220 bytes
B
216 bytes
C
212 bytes
D
210 bytes
Q:160 8086 can address a physical memory with address ranging from _______ to ________. A 0000H, FFFFH B 00000H, FFFFFH C
000H, FFFH
D
000000H, FFFFFFH
Q:161 What is the maximum size of data segment in 8086? A
16K
B
64K
C
32K
D
1M
Q:162 In 8086, base address is shifted ______ by _______ bits in the process of generating physical address. A Right, 4 B Left, 4 C
Right, 8
D
Left, 8
Q:163 In 8086, BIU performs the address calculation to fetch instruction from memory using ______ and _______ registers. A DS, DI B SS, SP C
ES, SI
D
CS, IP
Q:164 In 8086, stack physical address is calculated using ______ and _______ registers. A DS, DI B SS, SP C
ES, SI
D
CS, IP
Q:165 In 8086, which of the following register/s is/are used as offset register/s with DS to generate physical address? A IP B BX C
DI
D
BX, DI, SI
Q:166 In 8086, which of the following register/s is/are used as offset register/s with ES to generate physical address? A IP B BX C
DI
D
BX, DI, SI
Q:167 In 8086, if DS = 345BH and data segment length to be 12K bytes, what is the physical address range for data segment? A 345B0H to 365B0H B 345B0H to 385B0H C
345B0H to 375B0H
D
345B0H to 355B0H
Q:168 In 8086, if CS = 1111H and IP = 1232H, calculate the physical address for the addressed byte in code segment. A 12342H B 11110H C
23430H
D
01232H
Q:169 In 8086, if SS = 2526H, IP = 1232H, and SP = 1100H, calculate the physical address for the addressed byte in stack segment. A 26580H B 36260H C
26360H
D
37580H
Q:170 In 8086, if SS = 2526H, DS = 3333H, IP = 1232H, DI = 0020H, and SP = 1100H, calculate the physical address for the addressed byte in data segment. A 33350H B 26350H C
26580H
D
37580H
Q:171 We can have _______ logical address/es for the given physical address in 8086 A Only one B Only two C
Only three
D
One or more than one
Q:172 In 8086, instruction MOV AX, [2345H] represents _______ addressing mode. A Register B Immediate C
Direct
D
Register indirect
Q:173 In 8086, instruction MOV AL, [BX] represents _______ addressing mode. A
Register
B
Immediate
C
Direct
D
Register indirect
Q:174 In 8086, instruction MOV BX, 34E3H represents _______ addressing mode. A Register B Immediate C
Direct
D
Register indirect
Q:175 In 8086, instruction MOV DS, 2300H represents _______ addressing mode. A Register B Immediate C
Direct
D
Incorrect instruction
Q:176 In 8086, for the instruction MOV AL, 5[SI][BP], the effective address is _______. A 5 + BP + SI B SI C
BP + SI
D
BP
Q:177 In 8086, the instruction MOV AL, 5[SI][BP] represents ___________ addressing mode. A Register relative B Based indexed C
Relative based indexed
D
None of the above
Q:178 Which one of the following statements is true for the instruction MOV DS: [BP + 7], BL for 8086? A DS to be used instead of B SS to be used instead of DS SS C DS to be used instead of D DS to be used instead of ES CS Q:179 Which one of the following statements is true for the instruction MOV AX, CS:[BX] for 8086? A CS to be used instead of B DS to be used instead of CS SS C CS to be used instead of D SS to be used instead of CS DS Q:180 In 8086, the flag is ______ bits register. A
8
B
16
C
12
D
10
Q:181 In 8086, how many bits of flag register are used as control flags? A
6
B
3
C
7
D
9
Q:182 In 8086, how many bits of flag register are unused? A
6
B
3
C
7
D
9
Q:183 In 8086, how many bits of flag register are used as conditional flags? A
6
B
3
C
7
D
9
Q:184 In 8086, after the execution of following instruction, find the status of CF (carry flag) and S (sign flag). MOV AL, 35H ADD AL, 0CEH A CF = 0, S = 0 B CF = 1, S = 1 C
CF = 0, S = 1
D
CF = 1, S = 0
Q:185 In 8086, for near jump instruction, which of the following is true? A C
New IP = Current IP + 16bit offset New IP = 16-bit offset
B D
New IP = Current IP + 8-bit offset New IP = 8-bit offset
Q:186 In 8086, for short jump instruction, which of the following is true? A C
New IP = Current IP + 16bit offset New IP = 16-bit offset
B D
New IP = Current IP + 8-bit offset New IP = 8-bit offset
Q:187 In 8086, instruction JMP BX does ______ on execution. A
CS = BX
B
IP = BX
C
IP = IP + BX
D
Incorrect instruction
Q:188 In 8086, instruction JMP SI does ______ on execution. A
DS = SI
B
IP = SI
C
IP = IP + SI
D
Incorrect instruction
Q:189 In 8086, the instruction “LOOP label” does _______ on execution. A
CX is decremented and B BX is decremented and loop is loop is exited if CX = 0 exited if BX = 0 C CX is incremented and D BX is incremented and loop is loop is exited if CX = 0 exited if BX = 0 Q:190 In 8086, the instruction INC [BX] does _________ on execution. A
BX = BX + 1
B
BL = BL + 1
C
Add 1 to the content of D Incorrect instruction memory location pointed by BX Q:191 In 8086, the instruction ADC AX, [BX][SI] does ________ on execution. A C
AX + CF + (the data with EA = BX + SI) AX + (the data with EA = BX + SI)
B D
AX + CF + (the data with EA = BX) AX + CF + (the data with EA = SI)
Q:192 In 8086, the instruction SUB CL, BYTE PTR [SI] does ________ on execution. A CX – (Byte pointed by SI) B CL – (Byte pointed by SI) C
CL – (Byte pointed by SI) D Incorrect instruction – CF Q:193 In 8086, the instruction SBB CH, 7 does ________ on execution. A
CH – 7
B
CL – 7
C
CH – 7 – CF
D
Incorrect instruction
Q:194 In 8086, the instruction DEC WORD [SI] does __________ on execution. A
Incorrect instruction
B
(Word pointed by SI) – 1
C
(Byte pointed by SI) – 1
D
(Word pointed by SI) – 2
Q:195 For the instruction MUL BL in 8086, the content of BL is multiplied with ___________ and the result is stored in ___________. A AL, AX B AX, AX C
AH, AX
D
None of the above
Q:196 For the instruction MUL CX in 8086, the content of CX is multiplied with ___________ and the result is stored in ___________. A AX, DX B AX, DX and AX C
AX, AX
D
None of the above
Q:197 For the instruction DIV BYTE PTR [BX], the result on execution is __________. A Data in AX is divided by B Data in AL is divided by the the word pointed by BX byte pointed by BX C Data in AH is divided by D Data in AX is divided by the the byte pointed by BX byte pointed by BX Q:198 For the instruction DIV WORD PTR [SI], the result on execution is __________. A Double word data in AXB Double word data in DX-AX DX is divided by the is divided by the word pointed word pointed by SI by SI C Incorrect instruction D Data in AX is divided by the word pointed by SI Q:199 TEST dest, src instruction in 8086 does __________ on execution. A
C
Performs a logical AND of B the two operands updating the flag register without saving the result Performs a logical OR of D the two operands updating
Performs a logical XOR of the two operands updating the flag register without saving the result Performs a logical AND of the two operands updating the flag
the flag register without saving the result
register and saving the result
Q:200 In 8086, if AH = 00H, BL = 5EH, then the result of TEST AH, BL is __________. A Zero flag is set B Zero flag is reset C
Incorrect instruction
D
Zero flag not affected
Q:201 In 8086, if AL = 8CH, CH = 67H, then the result of XOR AL, CH is __________. A EBH B EAH C
FBH
D
FAH
Q:202 In 8086, the instruction SHL BX, 1 does on execution ___________. A
Content of BX is shifted B Content of BX is shifted left left logical by two position arithmetic by two position C Content of BX is shifted D Content of BX is shifted left left logical by one position arithmetic by one position Q:203 In 8086, the instruction SAL AL, CL does on execution ___________. A
Content of AL is shifted B Content of AL is shifted right left arithmetic by the count arithmetic by the count specified in CL specified in CL C Content of AL is shifted D Content of AL is shifted right left logical by the count logical by the count specified specified in CL in CL Q:204 In 8086, which instruction does “rotate through carry left”? A
SHR
B
RCL
C
ROL
D
RCR
Q:205 In 8086, which instruction does “rotate through carry right”? A
SHR
B
RCL
C
ROL
D
RCR
Q:206 In 8086, which instruction does “rotate right – not through carry”? A
ROR
B
RCL
C
ROL
D
RCR
Q:207 In 8086, which instruction does “rotate left – not through carry”? A
ROR
B
RCL
C
ROL
D
RCR
Q:208 In 8086, which control flag is set or reset to decrement or increment pointer registers in string operations? A DF B TF C
CF
D
IF
Q:209 In 8086, which register is loaded with the count value in string operations? A
BX
B
CX
C
DX
D
AX
Q:210 In 8086, MOVSB instruction does ____________ on execution. A
Data in the location B Data in the location pointed by pointed by SI to be moved DI to be moved to the location to the location pointed by pointed by SI, CX = CX – 1, DI, CX = CX – 1, SI = SI SI = SI + 1, DI = DI + 1 + 1, DI = DI + 1 C Data in the location D Data in the location pointed by pointed by SI to be moved SI to be moved to the location to the location pointed by pointed by DI, CX = CX – 1 DI Q:211 In 8086, REPE CMPSB instruction does __________ on execution. A
Compares string pointed by SP and BP byte by byte and update ZF Compares string pointed by SI and DI byte by byte
B
Compares string pointed by SI and BP byte by byte and update ZF C D Compares string pointed by SI and DI byte by byte and update ZF Q:212 In 8086, for SCASB instruction, the string to be scanned has to be in __________ and is to be pointed by ___________. A Extra, DI B Data, SI C
Extra, SI
D
Data, DI
Q:213 In 8086, for STOSW instruction, the memory where the data/string to be stored has to be in __________ and is to be pointed by ___________. A Extra, DI B Data, SI C
Extra, SI
D
Data, DI
Q:214 In 8086, for LODSW instruction, the destination register is _________. A
AL
B
AH
C
SI
D
AX
Q:215 In 8086, after the execution of following instructions, what will be the result in AL? MOV AL, ‘5’
ADD AL, ‘4’ AAA A AL = 69H
B
AL = 09H
C
D
AL = 39H
AL = 0AH
Q:216 In 8086, after the execution of following instructions, what will be the result in AL? MOV AL, ‘7’ ADD AL, ‘6’ AAA A AL = 13 B AH = 01 AL = 03 C
AL = 6DH
D
AH = 03 AL = 01
Q:217 In 8086, which instruction is used for “ASCII adjust AX after multiplication?” A AAM B AAA C
AAD
D
AAS
Q:218 In 8086, which instruction is used for “ASCII adjust AL after addition?” A
AAM
B
AAA
C
AAD
D
AAS
Q:219 In 8086, which instruction is used for “ASCII adjust AL after subtraction?” A AAM B AAA C
AAD
D
AAS
Q:220 In 8086, which instruction is used for “ASCII adjust AX before division?” A
AAM
B
AAA
C
AAD
D
AAS
Q:221 In 8086, I/O addresses are limited to _________ bits for IN and OUT instructions. A 8 B 16 C
12
D
20
Q:222 In 8086, the instruction IN AX, 67H does ____________ on execution. A
Gets 16-bit data into AX B Gets 8-bit data into AL from from port with address port with address 67H 67H C Gets 8-bit data into AH D None of the above from port with address 67H Q:223 In 8086, the instruction CBW does ___________ on execution. A C
Copies D7 bit of AL to all the bits of AH Copies D7 bit of BL to all
B D
Copies D7 bit of AH to all the bits of AL Copies D7 bit of BH to all the
the bits of BH
bits of BL
Q:224 In 8086, the instruction CWD does ___________ on execution. A
Copies D15 bit of AX to all B Copies D15 bit of DX to all the the bits of DX bits of AX C Copies D15 bit of BX to all D Copies D15 bit of CX to all the the bits of CX bits of BX Q:225 In 8086, instruction IN AX, 12H does ________ on execution. A
Copies 12H into AX
B
Copies 16-bit data from port with address 12H into AX C Copies 12H into AL D Copies 8-bit data from port with address 12H into AX Q:226 In 8086, instruction IN AL, 45H does ________ on execution. A
Copies 45H into AL
B
A
8
B
16
C
12
D
20
Copies 16-bit data from port with address 45H into AX C Copies 45H into AH D Copies 8-bit data from port with address 45H into AL Q:227 8086 has _____ address lines multiplexed with data lines.
Q:228 Status lines S3 = _______ and S4 = _________ in 8086 if the current segment in use is data segment. A 1, 1 B 0, 0 C
1, 0
D
0, 1
Q:229 Status lines S4 = _______ and S3 = _________ in 8086 if the current segment in use is code segment. A 1, 1 B 0, 0 C
1, 0
D
0, 1
Q:230 Status lines S4 = _______ and S3 = _________ in 8086 if the current segment in use is stack segment. A 1, 1 B 0, 0 C
1, 0
D
0, 1
Q:231 Status lines S4 = _______ and S3 = _________ in 8086 if the current segment in use is extra segment. A 1, 1 B 0, 0 C
1, 0
D
0, 1
Q:232 In 8086, _________ and __________ signals are connected with direct memory access. A HOLD, INTR B HOLD, HLDA C Q:233
Q:234
D
INTR, READY
DT / R is ______ in transmit and ________ in receive for 8086. A
1, 0
B
0, 1
C
0, 0
D
1, 1
M / IO is ______ for I/O access and ________ for memory access in 8086. A 1, 0 B 0, 1 C
Q:235
HLDA, INTR
0, 0
D
1, 1
RD is ______ for read operation and WR ________ for write operation in 8086. A 1, 0 B 0, 1 C
0, 0
D
1, 1
Q:236 In 8086, TEST pin tested by the _________ instruction and tested instruction becomes _______ instruction when TEST pin is logic _____. A WAIT, NOP, 1 B NOP, WAIT, 1 C
WAIT, NOP, 0
D
NOP, WAIT, 0
Q:237 In 8086, _______ is used for interrupt request and ________ is used for interrupt acknowledge. A B INTR , INTA INTR , HLDA C
INTR, INTA
D
INTA , INTR
Q:238 ________ signal/pin is used to enable high memory bank of the data bus in 8086. A B BHE / S 7 BHE / S 7 C
BHE / S 7
D
BHE/S7
Q:239 ________ states are inserted when _________ pin is __________ in 8086. A
WAIT, READY, 0
B
READY, WAIT, 0
C
WAIT, READY, 1
D
READY, WAIT, 1
Q:240 If the operating frequency of 8086 is 10 MHz and for the given instruction, if machine cycle consists of 4-T states, what is time taken by machine cycle to complete execution of that instruction? A 4 µs B 0.4 µs C
40 µs
D
1 µs
Q:241 If the operating frequency of 8086 is 10 MHz and for the given instruction, if machine cycle consists of 4-T states, what is time taken by machine cycle to complete execution of that instruction when three wait states are inserted? A 0.7 µs B 0.4 µs C
70 µs
D
7 µs
Q:242 Which pin in 8086 microprocessor is used for maximum mode? A
MN / MX
B
MN / MX
C
MN / MX
D
MN/MX
Q:243 Which pin in 8086 is used to prevent other bus masters from accessing the bus? A B LOCK TEST C
DEN
D
None of the above
Q:244 How many minimum address pins are required to be connected/decoded to interface 2K X 8 memory chip with microprocessor? Assume chip select is permanently connected to the desired voltage level. A 13 pins B 10 pins C
12 pins
D
11 pins
Q:245 8086 microprocessor has _________ interrupts. A
Hardware, software
B
C
Software
D
C
2.33
D
Hardware
Hardware, software, and error generated Q:246 After execution of following statements in c program, what will be the value of c? int a =7, b = 3, c; c = a %b; A 1 B 2 None of the above
Q:247 After execution of following statements in c program, what will be the value of c? int a =7, b = 3, c; c = a/b;
A
1
B
2
C
2.33
D
None of the above
Q:248 After execution of following statements in c program, what will be the value of y? int k; float x, y; x =8; k = 3; y = x * (k/4); A 0 B 6.0 C
8.0
D
None of the above
Q:249 After execution of following statements in c program, what will be the value of y? int k; float x, y; x =8; k = 3; y = (x * k)/4; A 0 B 6.0 C
8.0
D
None of the above
Q:250 After execution of following statements in c program, what will be the value of x and y? int x = 6, y = 8; y = x++; A 7, 6 B 7, 7 C
6, 7
D
7, 8
Q:251 After execution of following statements in c program, what will be the value of x and y? int x = 6, y = 8; y = ++x; A 7, 6 B 7, 7 C
6, 7
D
7, 8
Q:252 What is the meaning of statement p = z++ in c-language? A
p = z + 1, z = z + 1
B
p = z + 1, z = z
C
p = z, z = z + 1
D
p = z, z = z
Q:253 What is the meaning of statement p = ++z in c-language? A
p = z + 1, z = z + 1
B
p = z + 1, z = z
C
p = z, z = z + 1
D
p = z, z = z
Q:254 What is the meaning of statement p += z in c-language? A
p = z;
B
p = p + z;
C
p = p * z;
D
Incorrect statement
Q:255 After execution of following statements in c program, what will be the value of variable sum? int n=123, sum=0, digit;
while (n!=0) { digit = n %10; sum += digit; n = n/10; } A
2
B
6
C
1
D
123
Q:256 In c-language, which looping statement does execute at least once? A
Do While
B
While
C
For
D
None of the above
Q:257 In c-language, the statement “int a[20][20]” results into variable a with _________ number of total elements? A 40 B 20 C
400
D
None of the above
Q:258 In c-language, the statement “int a[20][20]” results into variable a with 1st index ranging from ____ to ____ and 2nd index ranging from _____ to _____? A 0, 19, 0, 19 B 1, 20, 1, 20 C
1, 19, 1, 19
D
0, 20, 0, 20
Q:259 Which of the following statement is correct when variable a is declared to be of integer type in c-language? A scanf(“%d”, a) B scanf(“%d”, &a) C
scanf(“%ld”, &a)
D
scanf(“%f”, &a)
Q:260 Which of the following statement is correct when variable a is declared to be of float type in c-language? A scanf(“%d”, a) B scanf(“%d”, &a) C
scanf(“%ld”, &a)
D
scanf(“%f”, &a)
Q:261 Which of the following statement is correct when variable a is declared to be of long integer type in c-language? A scanf(“%d”, a) B scanf(“%d”, &a) C
scanf(“%ld”, &a)
D
scanf(“%f”, &a)
Q:262 Which of the following statement is correct when variable a is declared to be of double type in c-language? A scanf(“%d”, a) B scanf(“%d”, &a) C
scanf(“%lf”, &a)
D
scanf(“%f”, &a)
Q:263 Which statement in c-language is used to proceed with the next value of iterative variable in for statement? A Break B Continue C
Exit
D
None of the above
Q:264 Which statement in c-language is normally used to prevent from continuing from one case to another case in switch statement? A Break B Continue C
Exit
D
None of the above
Q:265 How can we declare an integer pointer variable (e.g. y) in c-language? A
int *y;
B
int y;
C
int &y;
D
None of the above
Q:266 In c-language, how can we point an integer pointer variable (e.g. y) to point to integer variable (e.g. x)? A y = x; B y = &x; C
y = *x;
D
None of the above
Q:267 In c-language, how can we access the value from a pointer variable (e.g. y) and can assign it to another variable z? A z = *y; B z = &y; C
z = y;
D
None of the above
Q:268 In c-language, array variable name points to _____ element of the array? A
Last
B
1st
C
Middle
D
None of the above
Q:269 In c-language, if a and b are integer variable, what will be the result on execution of following statement? a = *(&b); A Incorrect statement B Values of a and b are same C
a is assigned with address D Values of a and b are not same of b Q:270 In c-language, what will be the result on execution of following statements? x = 5; y = 10; max = (x > y) ? x : (x+y); A max = 10 B max = 5 C
max = 15
D
Incorrect statement
Q:271 In c-language, file can be opened in _______ mode/s? A
Read,
B
Write
C
Append
D
All of the above
Q:272 In c-language, how can we declare file pointer? A
FILE *fp;
B
FILE fp;
C
FILE &fp;
D
None of the above
Q:273 In c-language, what is the effect on execution of following statements? FILE *fp; fp = fopen(“sample.dat”,“r” ); A Declares file pointer B Declares file pointer variable variable fp fp and opens file “sample.dat” in read mode C Declares file pointer D None of the above variable fp and opens file “sample.dat” in write mode Q:274 In c-language, what is the effect on execution of following statements? FILE *fp; fp = fopen(“sample.dat”,“r” ); A Declares file pointer B Declares file pointer variable variable fp fp and opens file “sample.dat” in read mode C Declares file pointer D None of the above variable fp and opens file “sample.dat” in write mode Q:275 In c-language, what is the effect on execution of following statements? FILE *fp; fp = fopen(“sample.dat”,“a” ); A Declares file pointer B Declares file pointer variable variable fp fp and opens file “sample.dat” in read mode C Declares file pointer D Declares file pointer variable variable fp and opens file fp and opens file “sample.dat” “sample.dat” in write in append mode mode Q:276 In c-langauge, which statement is used to read from a file? A
scanf
B
fscanf
C
fopen
D
None of the above
Q:277 In c-langauge, which statement is used to write into a file? A
printf
B
fprintf
C
fopen
D
None of the above
Q:278 In c-language, how can we verify the successful opening of a file?
A
Comparing file pointer B Comparing file pointer with with EOF EXIT C Comparing file pointer D None of the above with NULL Q:279 In c-langauge, which file function is used to position the file pointer to the start of the file? A rewind B fclose C
fgets
D
None of the above
Q:280 In c-language, how many bytes are required to store value of integer variable? A 1 B 2 C
3
D
4
Q:281 In c-language, how many bytes are required to store value of double variable? A 1 B 2 C
8
D
4
Q:282 In c-language, how many bytes are required to store value of float variable? A 1 B 2 C
8
D
4
Q:283 In c-language, how many bytes are required to store value of char variable? A 1 B 2 C
8
D
4
Q:284 In c-language, what is the range of values permitted for integer variable? A
0 to 255
B
0 to 65535
C
-32768 to 32767
D
None of the above
Q:285 In c-language, what is the range of values permitted for unsigned integer variable? A 0 to 255 B 0 to 65535 C
-32768 to 32767
D
None of the above
Q:286 In c-language, what is the range of values permitted for unsigned char variable? A 0 to 255 B 0 to 65535 C
-32768 to 32767
D
None of the above
Q:287 In c-language, what is the range of values permitted for char variable? A
0 to 255
B
0 to 65535
C
-128 to 127
D
None of the above
Q:288 In c-language, compiler automatically assigns _____ to first value in enumerated data type. A 0 B 1 C
2
D
None of the above
Q:289 Which of the following is/are storage classes available in c-language? A
Register, auto
B
Static
C
Extern
D
Register, auto, static, extern
Q:290 Which of the following is the valid statement to define constant in clanguage? A define MAX 100 B #define MAX 100 C
# define MAX 100
D
#define MAX 100;
Q:291 Which one of the following is bitwise shift left operator in c-language? A
&
B
<<
C
^
D
>>
Q:292 Which one of the following is bitwise exclusive OR operator in clanguage? A & B << C
^
D
>>
Q:293 In c-language, find the value of x on execution of following statements. float a, b, c, x; a = 9; b = 12; c =3; x = a – b/3 + c*2 – 1; A 10.0
B
7.0
C
D
None of the above
4.0
Q:294 In c-language, find the value of x on execution of following statements. float a, b, c, x; a = 9; b = 12; c =3; x = a – b/(3 + c)*(2 – 1); A 10.0
B
7.0
C
D
None of the above
4.0
Q:295 In c-language, find the value of x on execution of following statements. float a, b, c, x; a = 9; b = 12; c =3; x = a – (b/(3 + c)*2) – 1;
A
10.0
B
7.0
C
4.0
D
None of the above
Q:296 In c-language, what will be the result on execution of following statements? int a; a = (int)21.3/(int)4.5; A
5
B
4.73
C
5.25
D
None of the above
Q:297 In c-language, what will be the result on execution of following statements? int x; float y = 27.6; x = (int)(y + 0.5); A
28.1
B
28
C
27
D
None of the above
Q:298 In c-language, what will be the result on execution of the following statements? for(x=9; x<9 ; x = x – 1) printf(“%d”, x); A printf will never be B printf will be executed infinite executed times C printf will be executed one D printf will be executed 10 time times Q:299 In c-language, what will be the result on execution of the following statements? for(x=9; x>=0 ; x = x – 1) printf(“%d”, x); A printf will never be B printf will be executed infinite executed times C printf will be executed one D printf will be executed 10 time times Q:300 In c-language, what will be the result on execution of the following statements? for(j=1000; j > 0; j = j – 1); printf(“%d”, j); A printf will never be executed C printf will be executed one time
B D
printf will be executed infinite times printf will be executed 1000 times
1
2
3
4
5
6
7
8
Determine the values of A, B, C that make the sum term A'+ B' +C equal to 0. A A=0, B=1,C=0
B A=1, B=0,C=0
C A=1, B=1,C=0
D A=1, B=1,C=1
X+X.Y =……. A X
B 1+Y
C Y
D None of these
The circuit shown in Figure represents _________ gate.
A AND.
B NAND.
C OR.
D NOR.
CMOS logic has the property of A increased capacitance and delay.
B decreased area.
C high noise margin.
D low static power dissipation.
For a 12-bit flash ADC, the number of comparators required are A 4097
B 2047
C 4095
D None of these
A 32 to 1 multiplexer has the following features. A 32 outputs, one input and 5 control signals
B 32 inputs, one output and 5 control signals
C 5 inputs, one control signal and 32 outputs
D 5 inputs,32 control signal and one outputs
Given a MOD-12 ripple counter using a J-K flip-flop. If the clock frequency to the counter is 40 KHZ , then the output frequency of the counter is…. A 40 khz
B 12 khz
C 3.33 khz
D None of these
The exact number of flip flops requierd to construct a MOD 10 counter is
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9
A 5
B 10
C 2
D 4
The number of address bits needed to operate a 2K × 8-bit RAM are: A 9
B 11
C 15
D 25
10 A one-to-sixteen demultiplexer requires A 2 select input line
B 4 select input line
C 5 select input line
D 8 select input line
11 EPROM contents can be erased by exposing it to
12
A Infrared rays.
B Ultraviolet rays.
C Burst of microwaves
D None of these
The Gray code for decimal number 6 is equivalent to A 1100
B 1001
C 0101
D 0110 13 The output of a logic gate is 1 when all its inputs are at logic 0. the gate is either A a NAND or an EX-OR
B an OR or an EX-NOR
C an AND or an EX-OR
D a NOR or an EX-NOR
14 The speed of conversion is maximum in A Successive-approximation A/D converter.
B Parallel-comparative A/D converter.
C Counter ramp A/D converter.
D Dual-slope A/D converter.
15 When simplified with Boolean Algebra (x + y)(x + z) simplifies to A x
B x + x(y + z)
C x(1 + yz)
D x + yz
16 The gates required to build a half adder are A EX-OR gate and NOR gate
B EX-OR gate and OR gate
C EX-OR gate and AND gate
D Four NAND gates.
17 The code where all successive numbers differ from their preceding number by single bit is A Binary code.
B BCD.
C Excess – 3
D Gray.
18 If the input to T-flipflop is 100 Hz signal, the final output of the three T-flipflops in cascade is
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A 1000 Hz
B 500 Hz
C 333 Hz
D 12.5 Hz.
19 For which of the following flip-flops, the output is clearly defined for all combinaMons oftwo inputs. A D type flip-flop.
B R-S flip-flop.
C J-K flip-flop.
D none of these
20 The digital logic family which has the lowest propagation delay time is A ECL
B TTL
C CMOS
D PMOS
21 In digital ICs, Schottky transistors are preferred over normal transistors because of their A Lower Propagation delay.
B Higher Propagation delay.
C Lower Power dissipation.
D Higher Power dissipation.
22 Which TTL logic gate is used for wired ANDing A Open collector output
B Totem Pole
C Tri state output
D ECL gates
23 Advanced Low Power Schottky is a part of A ECL family
B TTL family
C CMOS family
D None of these
24 Shifting a register content to left by one bit position is equivalent to A division by two.
B addition by two.
C multiplication by two.
D subtraction by two.
25 How many two-input AND and OR gates are required respectively to realize Y=CD+EF+G A 2,2.
B 2,3.
C 3,3.
D none of these.
26 Which of following can not be accessed randomly A DRAM.
B SRAM.
C ROM.
D Magnetic tape.
27 Karnaugh map is used for the purpose of A Reducing the electronic circuits used.
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B To map the given Boolean logic function.
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C
To minimize the terms in a Boolean expression.
D
To maximize the terms of a given Boolean expression.
28 A full adder logic circuit will have A Two inputs and one output.
B Three inputs and three outputs.
C Two inputs and two outputs.
D Three inputs and two outputs.
29 The information in ROM is stored A By the user any number of times. C By the user using ultraviolet light.
B By the manufacturer during fabrication of the device. D By the user once and only once.
30 A weighted resistor digital to analog converter using N bits requires a total of A N precision resistors.
B 2N precision resistors.
C N + 1 precision resistors.
D N – 1 precision resistors.
31 Which of the following memories stores the most number of bits A 8 K 64 × memory
B 8 M1 × memory.
C 8 M 32 × memory.
D
64K× 6 memory.
32 What is the end address of 8k X 8 memory ,if the starting address is AAOOH? A B9FFH
B C9FFH
C AAFFH
D B900
33 The Boolean function f(w,x,y,z ) = ∑ m (5,7,9 ,11 ,13, 15) is independent of variables.
34
A w
B x
C y
D z and x
The contents of BC register pair after the execution of the following program in an 8085 microprocessor is ………..... LXI H,7585 H LXI B, 4774 H PUSH B XTHL POP B HLT A 7585
B 4774
C 8575
D 7447
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35 Which of these statements are true? (1) A flip-flop can store 1-bit information (2) Race condition occurs in a J-K flip flop when both inputs are 1 (3) Master Slave configuration is used in flip flops to stroe 2- bits of data. (4) A transparent latch consists of a D-type flip-flop. A
1 & 2 only
C 1,2 and 4
B 1,3 and 4 D 2 and 3
36 Pick up the correct statement(s) from the following: (P) Open collector outputconfiguration enables to generate OAI logic. (Q) Power consumption is minimum in CMOS family. (R ) Minimum two transistors are required to construct dynamic RAM cell. (S) Single comparator is used in successive approximation type of ADC. A P,R & S
B
C Q&S
D R&S
Q&R
37 A 6 bit DAC use binary weighted resistors. If MSB resistor is 10 k ohm, the value of LSB resistor Is A 40 k ohm
B 80 k ohm
C 640 k ohm
D 320 k ohm
38 As the number of flip flops are increased, the total propagation delay of ripple counter increases, but that of synchronous counter remains the same Both ripple counter and synchronous C counter increases.
A
B Both ripple counter and synchronous counter decreases. D None of these
39 To convert J K flip flop to D filp flop. A short both J and K and connect D to it. C Connect D to K and leave J open.
B Connect D to J Directly and D to K through inverter. D Connect D to J and leave K open.
40 The advantage of using dual slope ADC in digital voltmeter is that A its conversion time is very small.
B its accuracy is very high.
C it does not require a comparator
D None of these
41 The noise margin of a TTL gate is about A 1.2 V
B 0.2 V
C 0.4 V
D 0.8 V
42 A memory system of size 32 k bytes is reqiured to design using memory chips which have 12 address lines and 4 data lines each. The number of such chips reqiured to design the memory system is A 4
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B 8
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C 16
D 32
43 An 8 bit ripple counter uses flip flops with propagation delay of 25 ns each. The maximum clock frequency which can be used is A 10 MHz
B 5 MHz
C 20 MHz
D 50 MHz
44 The application of shift registors are : (1) serial to parallel data conversion (2) parallel to serial data conversion (3) Provide delay to the input A 1,2
B 2,3
C 1,2,3
D none of these.
45 find the correct statement. A
ROM is a Volatile memory while RAM is a Non Volatile memory.
C Both ROM and RAM are Non Volatile
B Both ROM and RAM are Volatile D
RAM is a Volatile memory while ROM is a Non Volatile memory.
46 For a logic famliy correct relationship is A VOH > VIH > VOL > VIL
B VIH > VOH > VIL > VOL
C VOH > VIH > VIL > VOL
D None of these
47 A 10 bit ADC is used to convert analog voltage of 0 to 10 V into digital. The resolution is A 4.88 m V
B 9.775 m V
C 20 m V
D None of these
48 To design a sequential circuit having 11 states, minimum number of memory elements required is A 5
B 3
C 4
D 11
49 A 4 input NAND gate is to be used as an inverter. Which is preferrable ? A the three unused inputs are left open
B the three unused inputs are connected to 0
C the three unused inputs are connected to 1
D none of these
50 which are charcterstics of sequential circuits ? (1) Feed back (2) output depends on previous inputs (3) gates are arranged in sequence. A 1,3
B 1,2
C 2,3
D none of these
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51 The number of address bits needed to operate a EPROM 8192 X 8 is A 4
B 8
C 12
D 13
52 Which one of the following is D/A conversion technique A dual slope
B weighted resistor
C Successive-approximation.
D none of these
53 The figure of merit for a logic family is A fan out X fan in
B propagation delay time X power dissipation
C gain bandwith product
D none of these
54 To count 2500 bottles in cold drink plant, the minimum number of flip flops requered is A 8
B 10
C 12
D 16
55 One XOR gate can work as A one bit magnitude comparator C
both one bit magnitude comparatoe and an inverter
B an inverter D none of these
56 which is non-saturating logic family A CMOS
B TTL
C ECL
D none of these
57 The power dissipation per gate A increases with frequency
B decreases with frequency
C remain constant with frequency
D none of these
58 Quantzation error occurs in A D/A converter
B A/D converter
C both D/A and A/D converter
D none of these
59 A binary ladder network D/A converter requires A resistor of one value only
B resistor of many different values
C resistor of two different values
D none of these
60 If number of bits is N, the % resolution in analog to digital conversion is A 100/2N+1
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B 100/2N-1
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D 100/2N
C 100/N 61 Internal structure of PLA : A only AND array programmable
B only OR array programmable
C both OR & AND array programmable
D none of these
62 The accuracy of A/D conversion is generally A ±LSB
B ±1/2LSB
C ±1/4LSB
D none of these
63 Which memory requires periodic recharging A All RAMS
B Dynamic RAM
C EPROMS
D static RAM
64 If number of information bits is 11, the number of parity bits in Hamming code is A 2
B 3
C 4
D 5
65 A buffer is A Always inverting
B Always non-inverting
C inverting or non-inverting
D none of these
66 In--------- function each term is known as min term. A POS
B Hybrid
C SOP
D none of these
67 In--------- function each term is known as max term A Hybrid
B SOP and Hybrid
C POS
D SOP
68 Which stack is used in 8085? A FIFO
B LIFO
C FILO
D None of these
69 Why 8085 is called an 8 bit processor? A because 8085 has 8 bit address bus.
B because 8085 has 8 bit data bus and 8 bit ALU.
C because 8085 has 8 bit stack pointer
D None of these
70 Which is not a flag of 8085? A Overflow Flag
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B sign Flag
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C carry Flag
D zero flag
71 In 8085 microprocessor how many I/O devices can be interfaced in I/O mapped I/O technique? A Either 256 input devices or 256 output devices B 256 input output devices C
256 input devices and 256 output devices
D none of these
72 In an 8085 microprocessor, the instruction CMP B has been executed while the contents of accumulator is less than that of register B. As a result carry flag and zero flag will be respectively A Reset,Reset
B Set, Reset
C set,set
D reset,set
73 To put the 8085 microprocessor in the wait state A Lower the HOLD input
B Lower the READY input
C rise the HOLD input
D rise the READY input
74 The TRAP is one of the interrupts available its INTEL 8085. Which one of the following statements is true of TRAP? A It is level triggered B It is edge triggered C It is level triggered and positive edge triggered 75 A dynamic RAM consists of
D None of these
A 6 transistors.
B 2 capacitors only.
C 2 transistors and 2 capacitors.
D 1 transistor and 1 capacitor.
76 A PLA can be used A as a microprocessor.
B as a dynamic memory.
C to realize a combinational logic.
D to realize sequential logic.
77 The following questions have two statements Assertion (A), and Reason(R) . Examine them and answer as per the following code. A. Schottky transistors are preffered over normal transistors in digital circuits. R. Schottky transistor when used as a switch, switches between cuttoff and active region. A
Both A and R are correct and R is correct explanation of A
C A is true, R is false
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B
Both A and R are correct but R is not correct explanation of A
D A is false, R is true
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78
The circuit in Fig is used to realize the logic function of
A Inverter.
B NOR gate.
C NAND gate.
D XOR gate.
79 The following questions have two statements Assertion (A), and Reason(R) . Examine them and answer as per the following code. A.Boolean expressions can be easily simplified using K-map. R. K-map can be drawn for minterms as well as maxterms. A
Both A and R are correct and R is correct explanation of A
B
C A is true, R is false
Both A and R are correct but R is not correct explanation of A
D A is false, R is true
80 What J-K input condition will always set ‘Q’ upon the occurrence of the active clock transition? A J = 0, K = 0
B J = 1, K = 1
C J = 1, K = 0
D J = 0, K = 1
81 The Boolean Expression A'B + AB'+AB is equivalent to. A AB
B A+B
C AB'
D (A+B)'
82 A ring counter consisting of five Flip-Flops will have A 5 states
B 32 states
C 16 states
D None of these
83 A device which converts BCD to Seven Segment is called A Multiplexer
B Demultiplexer
C Encoder
D Decoder
84 The A/D converter whose conversion time is independent of the number of bits is A Dual slope
B Successive approximation.
C Parallel conversion
D Counter type
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85
A 4-bit synchronous counter uses flip-flops with propagation delay times of 15 ns each. The maximum possible time required for change of state will be A 15 ns
B 30 ns
C 45 ns
D 60 ns
86 Boolean Algebra obeys A Associative law
B Commutative law
C Distributive law
D All of these
87 In a four variable Karnaugh map two adjacent cells give a A Three variable term
B Single variable term
C Two variable term
D Four variable term
88 Large screen integration refers to A More than 10 gates on the same chip
B More than 25 gates on the same chip
C More than 75 gates on the same chip
D More than 100 gates on the same chip
89 The minimum number of 2 input NAND gates required to implement boolean function X Y ' Z , if X,Y,Z are available A 2 B 3 C 4
D 5
90 If the functions W,X,Y,Z are as follows: W = R+P'Q+ R'S ; X =PQR'S'+ P'Q'R'S'+PQ'R'S' ; Y = RS + (PR + PQ'+P'Q')' ; Z= R+S+(PQ + P'Q'R'+PQ'S')'
A W=Z, X=Z'
B W=Z, X=Y
C W=Z,X=Y'
D W=Y=Z'
91 The Boolean Expression Y=A'B'C'D+A'BCD'+AB'C'D+ABC'D' can be minimized to
A Y=A'B'C'D + A'BC'+AC'D
B Y = A'B'C'D+ BCD'+AB'C'D
C Y=A'BCD' +'B'C'D+AB'C'D
D Y=A'BCD' + B'C'D + ABC'D'
92 A 2bit binary multiplier can be implemented using A XOR gates and multiplexer
B 2 input ANDs only
C 4 input NOR and multiplexer
D None of these.
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93 The output Y of a 2-bit comparator is logic 1 whenever the 2 bit input A is greater than the 2 bit input B. The number of combinations for which the output is logic 1 is A 4
B 6
C 8
D 10
94 For a binary half subtractor having two inputs A and B , the correct set of logical expressions for the outputs D = A-B and X (=borrow) are A D=AB+A'B, X= A'B
B D= A'B+AB', X = AB'
C D= A'B+AB', X = A'B
D None of these.
95 The following program starts at Location 0100H LXI SP, 00FF LXI H,0107 MVI A,20H SUB M The contents of accumulator when the program counter reaches 0209H is A 20H
B 02H
C 00H
D FFH
96 In an 8085 microprocessor system, the RST instruction will cause an interrupt Only if an interrupt service routine is not B Only if a bit in the inturrept mask is made 0. being executed. Only if inturrepts have been enabled by an C D none of these. EI instruction 97 If CS = A'15 A14A13 is used as the chip select logic of 4K RAM in an 8085 system, then its memory range will be A 3000H - 3FFFH B 7000H - 7FFFH A
C 5000H - 5FFFH and 6000H - 6FFFH 98
D 6000H - 6FFFH and 7000H - 7FFFH
The following questions have two statements Assertion (A), and Reason(R) . Examine them and answer as per the following code. A. A PROM can be used as a synchronous counter. R. Each memory location in a PROM can be read synchronously. A
Both A and R are correct and R is correct explanation of A
C A is true, R is false
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B
Both A and R are correct but R is not correct explanation of A
D A is false, R is true
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99
The following questions have two statements Assertion (A), and Reason(R) . Examine them and answer as per the following code. A. Gray code is used in shaft position encoding. R. In gray code only a single bit change occurs when going from one code to another. A
Both A and R are correct and R is correct explanation of A
C A is true, R is false
B
Both A and R are correct but R is not correct explanation of A
D A is false, R is true
100 The following questions have two statements Assertion (A), and Reason(R) . Examine them and answer as per the following code. A.ECL gate has very high speed of operation R. Trsistors in ECL do not go into saturation region. A
Both A and R are correct and R is correct explanation of A
C A is true, R is false
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B
Both A and R are correct but R is not correct explanation of A
D A is false, R is true
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1
2
3
4
5
The early effect in a bipolar junction transistor is caused by A fast turn-on
B fast turn-off
C large collector-base reverse bias
D large emitter-base forward bias
The breakdown mechanism in a lightly doped p-n junction under reverse biased condition is called A avalanche breakdown.
B zener breakdown.
C breakdown by tunnelling.
D high voltage breakdown.
For a large values of |VDS|, a FET – behaves as A Voltage controlled resistor.
B Current controlled current source.
C Voltage controlled current source.
D Current controlled resistor.
Space charge region around a p-n junction A does not contain mobile carriers
B contains both free electrons and holes
C contains electrons only as free carriers
D contains holes only as free carriers
The reverse – saturation current of a silicon diode A doubles for every 10°C increase in temperature
B does not change with temperature
C doubles for every 10°C decrease in temperature D None of these 6
7
8
9
Transistor is a A Current controlled current device.
B Current controlled voltage device.
C Voltage controlled current device.
D Voltage controlled voltage device.
In the voltage regulator shown below, if the current through the load decreases,
A The current through R1 will increase.
B The current through R1 will decrease.
C zener diode current will increase.
D zener diode current will decrease.
For a JFET, when VDS is increased beyond the pinch off voltage, the drain current A Increases
B decreases
C remains constant.
D
Initially increases and then decreases
N-channel FETs are superior to P-channel FETs, because
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A They have large size
B They consume less power
C Mobility of electrons is greater than that of holes D They are easy to fabricate 10 n-type silicon is obtained by
11
A Doping with tetravalent element
B Doping with pentavalent element
C Doping with trivalent element
D Doping with a mixture of trivalent and tetravalent element
The forward characteristic of a diode has a slope of approximately 100mA/V at a desired point. The approximate incremental resistance of the diode is
A 50Ω
B 20Ω
C 100Ω
D 10Ω
12 When the temperature of a doped semiconductor is increased, its conductivity A increases
B decreases
C remains constant.
D increases or decreases depending on semiconductor type
13 A zener diode A Has a high forward voltage rating.
B Has a sharp breakdown at low reverse voltage.
C
D Has a negative resistance.
Is useful as an amplifier.
14 Field effect transistor has A large input impedance.
B large output impedance.
C large power gain
D large votage gain.
15 MOSFET can be used as a A current controlled capacitor
B voltage controlled capacitor
C current controlled inductor
D voltage controlled inductors
16 Thermal runaway is not possible in FET because as the temperature of FET increases A the mobility decreases
B the transconductance increases
C the drain current increases
D None of these
17 Which of the following is not associated with a p-n junction A junction capacitance
B charge storage capacitance
C depletion capacitance
D channel length modulation
18 Which of the transistor component is bigger in size? A Emmiter
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B Collector
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C Base
D All are of equal size
19 In which material do conduction and valence bands overlap ? A Conductor
B Semiconductor
C Dieelectric
D None of these
20 Hall Effect can be used A To find type of semi conductor (whether p OR n) B to find carrier concentration C to measure conductivity
D All of the above
21 Which statement is false as regards Transistors. A Base is lightly doped.
B Emmiter is moderately doped
C Collector is moderately doped.
D All statements are correct.
22 Thermionic emmision current is given by A Fermi Dirac distribution
B Maxwell's distribution
C Richardsons Dushman equation
D None of these.
23 In energy band diagram of p-type semiconductor the acceptor energy level is A Slightly above valence band
B
in valence band
C Slightly below valence band
D None of these.
24 Fermi level is the amount of energy which A a hole can have at room temperature C
B an electron can have at room temperature
must be given to an electron to move to conduction band
D None of these.
25 Which of the following has highest conductivity ? A Platinum
B Aluminium
C Tunguston
D Silver
26 When a reverse bias is applied to PN junction, the width of the depletion layer A Decreases
B increases
C remains constant.
D Initially decreases then remains constant
27 Surface leakage current is a part of A reverse current
B Forward current
C Forward breakdown
D Reverse breakdown
28 The cut in voltage of a diode is nearly equal to
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A applied forward voltage
B applied reverse voltage
C Barrier potential
D None of these.
29 A varactor diode is A reverse bised
B forward bised
C biased to breakdown
D unbiased
30 Which of these has highly doped p and n region? A PIN Diode
B Schottky diode
C Tunnel diode
D None of these
31 Which of these has semiconductor metal junction? A PIN Diode
B Schottky diode
C Tunnel diode
D None of these
32 Compared to Bipolar Junction Transistor ,a JFET has A Lower input impedance
B high input impedance and high voltage gain
C higher voltage gain
D high input impedance and low voltage gain
33 Compared to Bipolar Junction Transistor ,a FET has A Less noisy
B Has better thermal stability
C Has higher input impedance
D All of these
34 The following questions have two statements Assertion (A), and Reason(R) . Examine them and answer based on the following statements . (A) When a photoconductor device is exposed to light,its bulk resistance increases. (R) When exposed to light, electron hole pair are generated in the photoconducive device. A
Both A and R are correct and R is correct explanation of A
B
C A is true, R is false
Both A and R are correct but R is not correct explanation of A
D A is false, R is true
35 The following questions have two statements Assertion (A), and Reason(R) . Examine them and answer based on the following statements . (A) A PN junction diode is used as a rectifier (R) A PN junction diode has low resistance in forward direction and high resistance in reverse direction. A
Both A and R are correct and R is correct explanation of A
B
C A is true, R is false
SUJJECT CODE:
Both A and R are correct but R is not correct explanation of A
D A is false, R is true
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36
The following questions have two statements Assertion (A), and Reason(R) . Examine them and answer based on the following statements . (A) Intrinsic semiconductor is an insulator at 0 degree Kelvin. (R) Fermi level in intrinsic semiconductor is in the centre of forbidden energy band. A
Both A and R are correct and R is correct explanation of A
B
C A is true, R is false
Both A and R are correct but R is not correct explanation of A
D A is false, R is true
37 The following questions have two statements Assertion (A), and Reason(R) . Examine them and answer based on the following statements . (A) When a high reverse voltage is applied to a p-n junction the diode breaks down. (R) High reverse voltage causes avalanche effect. A
Both A and R are correct and R is correct explanation of A
B
C A is true, R is false
Both A and R are correct but R is not correct explanation of A
D A is false, R is true
38 The following questions have two statements Assertion (A), and Reason(R) . Examine them and answer based on the following statements . (A) In n-p-n transistor conduction is mainly due to electrons. (R) In n type materials electrons are majority carriers. A
Both A and R are correct and R is correct explanation of A
B
C A is true, R is false
Both A and R are correct but R is not correct explanation of A
D A is false, R is true
39 The following questions have two statements Assertion (A), and Reason(R) . Examine them and answer based on the following statements . (A) The amount of photo electric emission depends on the intensity of incident light. (R) Photo Electric emission can occur only if frequency of incident light is less than threshold frequency. A
Both A and R are correct and R is correct explanation of A
B
C A is true, R is false 40
Both A and R are correct but R is not correct explanation of A
D A is false, R is true
The following questions have two statements Assertion (A), and Reason(R) . Examine them and answer based on the following statements . (A) In intrinsic semiconductor the charge concentration increases with temperature. (R) At higher temperatures, the forbidden energy gap in semiconductors is lower. Both A and R are correct and R is correct explanation of A C A is true, R is false
Both A and R are correct but R is not correct explanation of A D A is false, R is true
A
SUJJECT CODE:
B
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41
The following questions have two statements Assertion (A), and Reason(R) . Examine them and answer based on the following statements . (A) In p-n-p transistor ,collector current is termed negative. (B) in a p-n-p transistor holes are majority carriers. A
Both A and R are correct and R is correct explanation of A
B
C A is true, R is false
Both A and R are correct but R is not correct explanation of A
D A is false, R is true
42 The following questions have two statements Assertion (A), and Reason(R) . Examine them and answer based on the following statements . (A) A Hall effect is used to find the type of semiconductor. (R) When a semiconductor carrying current I lies in a magnetic field , the force on electrons and holes is in opposite directions. Both A and R are correct but R is not correct Both A and R are correct and R is correct B A explanation of A explanation of A C A is true, R is false
D A is false, R is true
43 The following questions have two statements Assertion (A), and Reason(R) . Examine them and answer based on the following statements . (A) In a BJT, the base region is very thick. (R) In p-n-p transistor most of holes given off by emmiter diffuse through the base. A
Both A and R are correct and R is correct explanation of A
B
C A is true, R is false
Both A and R are correct but R is not correct explanation of A
D A is false, R is true
44 The voltage between the emitter and collector of a silicon transistor when the transistor is biased to be at the edge of saturation is:
45
A 5 volts.
B 10 volts.
C 0.1 volts.
D 0.3 volts.
In a transistor switch, the voltage change from base-to-emitter which is adequate to accomplish the switching [for silicon transistor] is only about
A 0.2 V.
B 5V
C 0.1 V
D 0.5 V.
46 The cut-in voltage of the aluminium n-type Schottky diode is about A 0.5 V.
B 0.5 Vµ .
C 0.35 V.
D 0.35 mV.
47 Which of the following has highest conductivity ?
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A copper
B Aluminium
C cast iron
D Mild steel
48 For a NPN BJT transistor to be in saturation mode: A VE< VB, VC< VB
B VE< VB, VC > VB
C VE> VB, VC< VB
D VE> VB, VC > VB
49 Which of the following statements best describes a forward biased silicon diode? A
The current through diode is exponentially related to the diode voltage.
B The voltage acrosss diode is 0 V
C The current through diode is 0 A.
D
The current through diode is of the form m Vd, where m is contant and Vd diode voltage
50 Which of the following statement is correct? (1 ) A P-channel MOSFET uses a n-type substrate or well (2) Conduction in a MOSFET channel is primarily due to Majority carriers A only 1
B only 2
C both 1 and 2
D None of these
51 When a BJT is operates under cut-off condition
52
A Both junctions are forward biased
B Both junctions are reverse biased
C CB in forward biased and EB is reverse biased
D None of these
Which is true about LASER diode? LASER means Light Amplification by stimulated emission of radiation C very small dimension
A
B It is monochromatic coherent light source D All of these
53 The types of carriers in a semiconductor are A 1
B 2
C 3
D 4
54 The number of protons in a silicon atom is A 32
B 28
C 14
D 4
55 The most commonly used semi conductor material is A Silicon
B Germanium
C Mixture of silicon and Germanium
D None of these
56 Holes act like
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A Poitive charges
B neutral atoms
C Negative charges
D crystals
57 Eddy current loss is A Proportional to frequency
B independent of frequency
C Proportional to ( frequency)2
D None of these
58 In an n type semiconductor A Number of free electrons and holes are equal Number of free electrons is less than number of holes 59 If α for a transistor is 0.98, β is equal to
B Number of free electrons is greater than number of holes
C
D none of these
A 52
B 49
C 48
D 46
60 Consider two well designed npn bipolar junction transistors , QA and QB. They are otherwise identical except base of QA is doped twice as heavily as the base of QB. The base emitter diode saturation current in Ebers Moll model, IES in transistor QA will be A Same as QB
B Less than QB
C Greater than QB
D None of these
61 Which of the following statements are correct: (1) Input impedance of a MOSFET is higher than that of a JFET. (2) In MOS transistor, triode region is the saturation region. (3) GaAsP LED produces light in visible region A 1 and 2
B 1 and 3
C 2 and 3
D 1, 2 and 3
62 The number of valence electrons in a donor atom is A 2
B 3
C 4
D 5
63 BJT acts like a switch by operating between these two regions: A cut-off and saturation
B cut-off and active
C saturation and active
D None of these
64 The power dissipation in transistors is the product of A Emitter current and VBE voltage
B Emitter current and VCE voltage
C Collector current and VCE voltage
D None of these
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65 For a N type MOSFET , substrate is----------- type A P type
B N type
C P type or N type depends on fabrication
D none of these
66 Most Negative characteristics of CMOS logic family is A High power dissipation
B Latch Up
C low speed
D None of these
67 polysilicon can be doped by A Diffusion
B Implantation
C Addition of dopant gases during deposition
D All these three methods
68 Resistivity of implanted polysilicon primarily depends on A Implant dose
B anneling temperature
C anneling time
D All these three
69 The merging of a hole and an electron is called A Recombination
B thermal bonding
C covalent bonding
D None of these
70 When a voltage is applied to a semiconductor crystal,the free electron will flow A towards positive terminal C
B towards negative terminal
either towards positive terminal ortowards negative terminal
D none of these
71 Which diode is used at microwave frequncies? A Varactor diode
B zener diode
C schottky diode
D PIN Diode
72 Which is the charactristic of FET
73
A It is an unipolar device
B Govern by majority and minority carrier
C Low input resiatance
D None of these
At sufficiently high temperatures some electrons acquire enough kinetic energy to escape from metal surface. This is called
A Thermionic emission
B secondary emission
C Field emission
D Photoelectric emission.
74 In BJT which current is the smallest? A Collector current
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B Base current
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C Emitter current
D Collector current and emitter current.
75 Which device converts solar radiation into electrical energy? A LED
B Photo voltaic device
C LDR
D None of these
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