Cape Physics Lab Unit 2 (2)

Lab #: 2 Topic: electric feld Aim: To draw electric felds lines to represent the electric feld around several symmetric charge distributions. Apparatus: simulation sotware and computer Procedure:

1. Open MS INTERNET EXPLORER. 2. Go to the site ELECTROSTATICS ELECTROSTATICS SIMULATION. http://www.f!st".#o$/e$stti#/ %. The si$&!tion sho&!" 'e open to  sin(!e so&)#e. *. +ese!e#t ,+)w ,+)w e-&ipotenti!s . Se!e#t ,E !ines/)ho/i 0. Un"e) Set&p se!e#t the #h)(e "ist)i'&tion fo) fo) the si$&!tion to show the )es&!tnt E!e#t)i# ie!" . E3p!o)e  n&$'e) of "iffe)ent #h)(e "ist)i'&tions. 4. On the L' Repo)t ")w t !est fi5e 67 e!e#t)i# e!e#t)i# fie!" !ines to )ep)esent the E!e#t)i# ie!" of the fo!!owin( #h)(e "ist)i'&tions: • • • • •

Sin(!e positi5e #h)(e Sin(!e ne(ti5e #h)(e 6not shown in si$&!tion7 +o&'!e positi5e #h)(e Positi5e n" ne(ti5e #h)(e 6"ipo!e #h)(e7 P)!!e! p!tes 6#on"&#tin( p!nes7

Result:

Discussion:

•

Why do electric feld lines never intersect?

What is meant by the concept that “charge is quantized?

Lab #: 3 Topic: electric field Aim: To investigate the relationship between between force and distance. distance. Apparatus: simulation software software and computer Procedure: 1. Open MS INTERNET INTERNET EXPLORER. EXPLORER. 2. Go to the site ELECTROSTATICS ELECTROSTATICS SIMULATION. SIMULATION. http://www.falstad.com/emstatic/  3. The simulation should should be open to a single source. source. 4. Deselect “Draw equipotentials” 5. Select “E lines/rho/i” 6. Under Setup select select the charge distribution for the simulation to show show the resultant Electric Field 7. Explore a number of different charge distributions. 8. Set the electric field option for more than on charges at the same post. 9. Find the electric field at different points on the simulation. 10. Complete the table below. 11. Plot a graph of force on the y-axis and distance square on the x-axis.

Result: Complete the table Distance (m) Electric field

force

Distance square

1 2 4 5 What do the graph say about the relationship? Find the gradient of the line. What does it represents? Discussion:

Lab#:4 Capacitor Lab Objectives: !. "#plore "#plore the e$ect e$ect o plate area% area% plate plate separate separate and dielectric dielectric materials materials on on the capacitance o a parallel plate capacitor. capacitor. &. 'evelop 'evelop an e#pression e#pression or or the capacitance capacitance o o a capacitor capacitor.. (. "#plore "#plore the e$ects o voltage% voltage% plate plate separation separation and a dielectric dielectric on the the electric feld strength between two charged plates. ). "#plore "#plore the e$ects e$ects o voltage voltage and capacita capacitance nce on the quantity quantity o charge charge stored on a capacitor plate and energy stored in the capacitor. capacitor. *. 'evelop 'evelop an e#pression e#pression or or the quantity quantity o charge charge stored stored on a capacitor plate. plate. +. 'evelop 'evelop an e#pression e#pression or or the energy energy stored stored in a capacitor capacitor in a circuit. circuit.

Materials: ,apacitor -ab applet at http:phet.colorado.eduensimulationcapacitor/lab 0clic1 Run 2ow34

Procedure & Analsis: •  •  •  • 

The following procedure for your reference only  Do not copy or cut & paste into your lab journal Discuss your own procedure in detail in your lab journal Include sketches or screen shots where necessary and construct your own data tables

!. 5he applet applet allows you you to e#amine e#amine various various properti properties es o a parallel parallel plate capacitor. capacitor. 6ou will need to continually measure the voltage% capacitance% charge on the top plate and the energy stored stored by the capacitor. capacitor. ,lic1 the appropriate appropr iate bo#es and position the meters to correctly do so. so. 5a1e a moment to get used to the controls and how to read each o the meters. &. 7witch to the “'ielectric “'ielectric  tab. 8n this this tab you will will investiga investigate te the e$ect o plate area% separation and dielectric materials on the capacitance o the capacitor. capacitor. 6ou should investigate the e$ect o each variable qualitatively at frst and classiy each relationship as either direct or inversely proportional.  5hen ma1e quantitative measurements measurements to develop an e#pression e#pression or the capacitance o the capacitor. capacitor. 6our e#pression should be 9ustifed by solid solid data. (. lso while while you;re you;re on this tab% e#amine e#amine how voltage% voltage% plate plate separation separation and the dielectric medium a$ect the electric feld strength between the parallel plates. 'iagrams o the electric feld feld vectors may be helpul in 9ustiying 9ustiying your conclusions. ). 7witch bac1 to the “
investigation. =se your data to develop develop an e#pression or the charge stored on the capacitor plate. *. -i1ewise% -i1ewise% perorm perorm a similar similar e#periment e#periment to develop develop an e#press e#pression ion or the energy stored in the capacitor.

Conclusion: 7ummarize what you;ve learned about capacitors rom this i nvestigation.