Essential University Physics, 3e (Wolfson) Chapter 38 Nuclear Physics
3 8. 1 Co nc e pt ua lQue s t i o ns 1) Consider two different isotopes of the same neutral element. Which statements about these isotopes are true? (There may be more than one correct choice.) A) Both isotopes contain the same number of neutrons. B) Both isotopes contain the same number of protons. C) Both isotopes contain the same number of nucleons. D) Both isotopes contain the same number of orbital electrons. ) The sum of the protons and neutrons neu trons is the same for both isotopes. Answer! B" D #ar! 1
$) Consider the short%li&ed neutral isotope represented by
'. Which of the followin
statements about this isotope are correct? (There may be more than one correct choice.) A) The isotope has $ nucleons. B) The isotope has $ protons. C) The isotope has $ neutrons. D) The isotope has 1 orbital electrons. ) The isotope has 1 protons. *) The isotope has 1+ neutrons. Answer! A" D" " * #ar! 1
,) Which of the followin statements about the atomic nucleus is co rrect? (There may be more than one correct choice.) A) -are nuclei are denser than liht nuclei. B) All nuclei ha&e nearly the same density. C) The nucleus is held toether more by the electrical force than by the ra&itational ra&itational force. D) A nucleus containin $+ nucleons will ha&e approimately twice the radius as a nucleus containin 1+ nucleons. ) As the number of nucleons increases the bindin enery per nucleon always increases. Answer! B #ar! 1
/) *or a
0b atom" the number of protons" neutrons" and electrons in the atom is
A) /1" $" ,. B) /1" $" $. C) /1" $" /1. D) /1" $" +. ) $" /1" +. Answer! C #ar! 1 1 Copyriht 2 $+13 4earson ducation" 5nc.
) The iron nucleus has the reatest bindin enery of any nucleus. A) True B) *alse Answer! B #ar! 1
3) 6oin from medium mass nuclei to hea&y nuclei" the a&erae bindin enery per nucleon A) decreases. B) beha&es randomly with no clear pattern. C) does not chane. D) increases. ) doubles. Answer! A #ar! 1
7) 8ea&ier stable nuclei tend to ha&e A) half as many protons as neutrons. B) the same number of neutrons and protons. C) more neutrons than protons. D) no clear trend in the relati&e number of neutrons and protons. ) more protons than neutrons. Answer! C #ar! 1
9) Which of the followin statements about the stron nuclear force are correct? (There may be more than one correct choice.) A) 5t acts e:ually on protons and neutrons but not on electrons. B) 5t acts e:ually on protons" neutrons" and electrons. C) 5t has a much loner rane than the electric force. D) 5t ;eeps electrons in their orbits around the n ucleus. ) Because of its &ery short rane" there is a limit to how lare the nucleus can be. Answer! A" #ar! 1
) 5f a nucleus decays by β by β % decay to a dauhter nucleus" which of the followin statements about this decay are correct? (There may be more than one correct choice.) A) The dauhter nucleus has more protons than the oriinal nucleus. B) The dauhter nucleus has more neutrons than the oriinal nucleus. C) The dauhter nucleus has the same number of nucleons as the oriinal o riinal nucleus. D) The dauhter nucleus has fewer protons than the oriinal nucleus. ) The dauhter nucleus has fewer neutrons than the oriinal nucleus. Answer! A" C" #ar! 1
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1+) 5f a nucleus decays by alpha decay to a dauhter nucleus" which of the followin statements about this decay are correct? (There may be more than one correct choice.) A) The dauhter nucleus has more protons than the oriinal nucleus. B) The dauhter nucleus has more neutrons than the oriinal nucleus. C) The dauhter nucleus has the same number of nucleons as the oriinal nucleus. D) The dauhter nucleus has fewer protons than the oriinal nucleus. ) The dauhter nucleus has fewer neutrons than the oriinal nucleus. Answer! D" #ar! 1
11) 5f a nucleus decays by amma decay to a dauhter nucleus" which of the followin statements about this decay are correct? (There may be more than one correct choice.) A) The dauhter nucleus has more protons than the oriinal nucleus. B) The dauhter nucleus has more neutrons than the oriinal nucleus. C) The dauhter nucleus has the same number of nucleons as the oriinal nucleus. D) The dauhter nucleus has fewer protons than the oriinal nucleus. ) The dauhter nucleus has fewer neutrons than the oriinal nucleus. Answer! C #ar! 1
1$) 5f a nucleus decays by β < decay to a dauhter nucleus" which of the followin statements about this decay are correct? (There may be more than one correct choice.) A) The dauhter nucleus has more protons than the oriinal nucleus. B) The dauhter nucleus has more neutrons than the oriinal nucleus. C) The dauhter nucleus has the same number of nucleons as the oriinal nucleus. D) The dauhter nucleus has fewer protons than the oriinal nucleus. ) The dauhter nucleus has fewer neutrons than the oriinal nucleus. Answer! B" C" D #ar! 1
1,) Which of the followin statements about β < decay are correct? (There may be more than one correct choice.) Durin β < decay A) an orbital electron is captured by the nucleus. B) a proton is emitted from the nucleus. C) a neutron in the nucleus decays to a proton and an electron. D) a proton in the nucleus decays to a positron and a neutron. ) the atomic number Z of the isotope increases by one unit but the atomic weiht A remains unchaned. Answer! D #ar! 1
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1/) A radioacti&e isotope decays by β % emission with a half%life of 1.+ min. Durin the first 1.+ min" a particular sample emits 1+++ β % particles. Durin the net 1.+ min" the number of β % particles this sample will emit will be closest to A) $+. B) ++. C) 1+++. D) 1++. ) $+++. Answer! B #ar! 1
1) A radioisotope has a half%life of τ at a temperature of 1+ =. 5f its temperature is increased to ,++ =" what will its half%life be? A) /τ B) $ τ C) τ D) τ >$ ) τ >/ Answer! C #ar! 1
13) The decay rate of an isotope is initially R+" but after one half%life has one by" the rate is R+>$. At the end of the 0'T half%life" what will the decay rate be? A) + B) R+ / 13 C) R+ /e D) R+>/ ) R+ /e$ Answer! D #ar! 1
17) The half%life of cobalt%3+ is ., years" while that of strontium%+ is $9 years. uppose you ha&e a sample of each" such that they initially contain e:ual numbers of atoms of these nuclides. 8ow will the acti&ities (number of decays per second) of the samples compare? A) The acti&ity of the cobalt%3+ sample will be reater. B) The acti&ities cannot be compared without more information. C) The acti&ities will be e:ual. D) The acti&ity of the strontium%+ sample will be reater. Answer! A #ar! 1
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19) The half%life of cobalt%3+ is ., years" while that of strontium%+ is $9 years. uppose that samples of cobalt%3+ and strontium%+ are such that they initially ha&e the same acti&ity (number of decays per second). What is true about the initial numbers of cobalt%3+ and strontium%+ nuclei in these samples? A) There are more strontium%+ than cobalt%3+ nuclei. B) There are e:ual numbers of cobalt%3+ and strontium%+ nuclei. C) There are more cobalt%3+ than strontium%+ nuclei. D) 5t is not possible to compare numbers of nuclei without ;nowin the masses of the samples. Answer! A #ar! 1
1) A radioacti&e nuclide of atomic number Z emits an electron" then the dauhter nuclide emits a amma ray. What is the atomic number of the resultin nuclide after both processes? A) Z < 1 B) Z % 1 C) Z % $ D) Z % , ) Z < $ Answer! A #ar! 1
$+) @odern nuclear bomb tests ha&e created an etra hih le&el of 1/C in our atmosphere. uppose that future archaeoloists date samples from our era" but do not ;now about this testin. Will their dates be too youn" too old" or still correct? 5f correct they are correct" why? A) too youn B) too old C) correct" because 1/C from bomb tests is different from that produced naturally D) correct" because modern bioloical materials do not ather 1/C from bomb tests Answer! A #ar! 1
$1) Which of the followin descriptions best describes the process by which en ery is released in a con&entional nuclear reactor? A) The radiation i&en off by a naturally radioacti&e substance" u ranium" is collected and used to ma;e steam. B) ranium is reacted with oyen in a combustion process that releases lare amounts of radioacti&ity and heat. C) Deuterium and tritium are oined toether to form helium. D) ranium" when bombarded by neutrons" splits into framents and releases two or three neutrons" and these neutrons in turn stri;e more uranium nuclei that split" thereby settin off a chain reaction that releases enery. ) A uranium nucleus is eneried to an ecited state by neutron irradiation" and it then dec ays by emittin beta rays and amma rays that heat water and create steam. Answer! D #ar! 1
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$$) The primary source of the enery radiated by a star" such as the sun" is A) beta decay. B) alpha decay. C) fission reactions in&ol&in uranium. D) fusion reactions in which hydroen is fused to form helium. ) fusion reactions in which helium is fused to form iron. Answer! D #ar! 1
$,) A fusion reaction releases enery because the bindin enery of the resultin nucleus A) is reater than the bindin enery of the oriinal nuclei. B) is e:ual to the bindin enery of the oriinal nuclei. C) is less than the bindin enery of the oriinal nuclei. D) is released in the process. ) is absorbed in the process. Answer! A #ar! 1
$/) 8ow does the mass of the products of a nuclear fusion reaction compare to the mass of the oriinal elements? A) The mass of the products is reater than the mass of the oriinal elements. B) The mass of the products is less than the mass of the oriinal elements. C) The mass of the products is e:ual to the mass of the oriinal elements. D) The mass of the products is unrelated to the mass of the oriinal elements. Answer! B #ar! 1
$) 5n massi&e stars" three helium nuclei fuse toether" formin a carbon nucleus. This reaction heats the core of the star. The net mass of the three helium nuclei must therefore be A) hiher than that of the carbon nucleus. B) less than that of the carbon nucleus. C) the same as that of the carbon nucleus since mass is always conser&ed. D) the same as that of the carbon nucleus since enery is always conser&ed. Answer! A #ar! 1
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3 8 . 2 Pr o bl e ms 1) A certain nucleus containin 9 protons and 7 neutrons has a radius R. Which of the followin &alues would be closest to the epected &alue of the radius of a nucleus ha&in 1 protons and 3 neutrons? A) 1.9 R B) $.++ R C) $.1/ R D) 3.,9 R ) 9.++ R Answer! B #ar! 1
$) A certain nucleus containin 9 protons and 7 neutrons has a density ρ. Which of the followin &alues would be closest to the epected &alue of the density of a nucleus ha&in 1 protons and 3 neutrons? A) 1.++ ρ B) 1.9 ρ C) $.++ ρ D) $.1/ ρ ) 9.++ ρ Answer! A #ar! 1
,) What would be the epected radius of a nucleus ha&in 9$ protons and 1$ neutrons? A) .$ fm B) . fm C) 3.+ fm D) 7.1 fm ) 17 fm Answer! D #ar! 1
/) What would be the epected radius of the nucleus of
r?
A) /.+ fm B) 1.$ fm C) ./ fm D) +.11 pm ) +./ pm Answer! C #ar! 1
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) 5f a nucleus had a diameter of 9.+ fm" what would be its epected mass" in atomic mass units? A) 7 u B) $3 u C) ,7 u D) 3/ u ) 1$9 u Answer! C #ar! 1
3) Two identical nuclei of mass 19 u are made to unite to ma;e a sinle nucleus of mass ,3 u. What is the radius of the result of this fusion? A) /.+ fm B) 3., fm C) /. fm D) 7.$ fm Answer! A #ar! 1
7) The followin masses are ;nown! n (neutron) 1.++933 u 8
1.++79$ u
*e 3.,, u
What is the bindin enery of
*e" in @e#? (1 u 1.33+ E 1+%$7 ; ,1. @e#>c$)
A) ++ @e# B) + @e# C) 31+ @e# D) 33+ @e# ) 71+ @e# Answer! A #ar! 1$
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9) The neutral deuterium atom"
8" has a mass of $.+1/1+$ uF a neutral hydroen atom has a
mass of 1.++79$ uF a neutron has a mass of 1.++933 uF and a proton has a mass of 1.++7$77 u. What is the bindin enery of the
8 nucleus? (1 u ,1.// @e#>c$)
A) 1.1 @e# B) 1.7 @e# C) $.$ @e# D) $. @e# ) ,./ @e# Answer! C #ar! 1
) What is the bindin enery per nucleon for
Al? The neutral
Al atom has a mass of
$3.91, uF a neutral hydroen atom has a mass of 1.++79$ uF a neutron has a mass of 1.++933 uF and a proton has a mass of 1.++7$77 u. (1 u ,1.// @e#>c$) A) 9., @e# B) 3.7 @e# C) ./ @e# D) ,./ @e# ) $.9 @e# Answer! A #ar! 1
1+) ranium%$,9 decays into thorium%$,/ plus an alpha particle. 8ow much enery is released in this process? 1 u ,1.// @e#>c$" and the rele&ant mass &alues are 8e! /.++$3+, u Th!
$,/.+/,9, u
! $,9.++793 u A) /.$9 @e# B) ,.73 @e# C) ,.19 @e# D) $.9 @e# ) .+ @e# Answer! A #ar! 1
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11) Gadium%$$3 decays into radon%$$$ plus an alpha particle. 8ow much enery is released in this process? 1 u ,1.// @e#>c$" and the rele&ant mass &alues are 8e! /.++$3+, u Gn!
$$$.+177+ u
Ga!$$3.+$/+$ u A) /.$/ @e# B) ,.73 @e# C) /.97 @e# D) .+ @e# ) ., @e# Answer! C #ar! 1
1$) 4lutonium%$, decays into uranium%$, plus an alpha particle. The enery released in the process is .$/ @e#. 6i&en the followin mass &alues 8e!
/.++$3+, u
! $,.+/,$/ u what is the mass of
4u in atomic mass units? (1 u ,1.// @e#>c$)
A) $,.+$1 u B) $,.+$77 u C) $,.++19 u D) $,9.1 u ) $,9.999/ u Answer! A #ar! 1
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1,) A stationary plutonium%$, nucleus decays into a u ranium%$, nucleus plus an alpha particle. The enery released in the process is .$/ @e#. 6i&en the followin mass &alues 8e! /.++$3+, u ! $,.+/,$/ u what is the ;inetic enery of the
nucleus? (1 u ,1.// @e#>c$)
A) +.+9$ @e# B) +.+9,7 @e# C) +.+9$ @e# D) +.+93, @e# ) +.+977 @e# Answer! #ar! 1
1/) The carbon in your body was formed in nuclear reactions in lon%dead stars. 8ow much enery was released when three /8e nuclei combined to ma;e 1$C? The mass of /8e is /.++$3+, u" the mass of 1$C is 1$.++++ u" and 1 u ,1.// @e#>c$. A) 7.$7/ @e# B) ,713 @e# C) 9./$/ @e# D) $.1+3 @e# Answer! A #ar! 1
1) 8ow much enery is released when 1./+ H of ,8 ha&e decayed to ,8e? The mass of ,8e is ,.+13+$ u" the mass of ,8 is ,.+13+/ u" and 1 u ,1.// @e#>c$. A) 9,+ I B) 11"++ I C) 77+ I D) 71"7++ I ) $,"++ I Answer! A #ar! 1
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13) The set of nuclear reactions that power our sun can be summaried a /p< J /8e<$ < $e<. The masses of the particles in&ol&ed are ,9.$7$ @e#>c$ (proton" p<)" ,7$7.,9 @e#>c$ (alpha particle" /8e<$)" and +.11 @e#>c$ (positron" e<). 8ow much enery is released by each set of these reactions? A) $/.3 @e# B) $9., @e# C) $7+ @e# D) $7 @e# Answer! A #ar! 1
17) A sphere made of a radioacti&e isotope initially has a mass of 3.99 ;. The half%life of this isotope is 1.,/ h" and it decays by β % emission. At the end of $.39 h" what is the mass of this sphere? A) 3.99 ; B) ,.// ; C) 1.7$ ; D) $., ; Answer! A #ar! 1
19) A radioacti&e atom has 9 protons and $/ nucleons. 5f it underoes alpha decay" what are the number of protons and nucleons" respecti&ely" in the dauhter nucleus? A) 1++" $/ B) /" $/7 C) 3" $/ D) 3" $/7 ) 1++" $/ Answer! C #ar! 1
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1) candium"
c" decays by emittin a positron. What is the nuclide that is the product of the
decay? A)
c
B)
c
C)
Ca
D)
Ca
)
c
Answer! C #ar! 1
$+) The stability of
C with respect to alpha" β <" and β % decay is to be determined. Do not
consider the possibility of decay by electron capture. The followin atomic masses are ;nown! 8e! /.++$3+, u Be! 7.+13$9 u B! 11.++,+ u C! 11.+11/,, u 0! 11.+$37/$ u
The
C nuclide is
A) not subect to alpha" β <" or β % decay. B) subect to alpha decay only. C) subect to β < decay only. D) subect to β % decay only. ) subect to β < or β % decay" but not to alpha decay. Answer! C #ar! 1 1, Copyriht 2 $+13 4earson ducation" 5nc.
$1) The stability of
c with respect to alpha" β <" and β % decay is to be determined. Do not
consider the possibility of decay by electron capture. The followin atomic masses are ;nown! 8e! /.++$3+, u =! /$.3+717 u Ca! /3.//, u c /3.$/+ u Ti! /3.173/ u The
c nuclide is
A) not subect to alpha" β <" or β % decay. B) subect to alpha decay only. C) subect to β < decay only. D) subect to β % decay only. ) subect to β < or β % decay" but not to alpha decay. Answer! D #ar! 1
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$$) The stability of
*e with respect to alpha" β <" and β % decay is to be determined. Do not
consider the possibility of decay by electron capture. The followin atomic masses are ;nown! 8e!
/.++$3+, u
Cr! 1.//739 u @n! .,9+7 u *e! .,/, u Co! .,9/1 u The
*e nuclide is
A) not subect to alpha" β <" or β % decay. B) subect to alpha decay only. C) subect to β
$,) A certain substance has a half%life of .+ hours. 8ow many nuclei of the substance are re:uired to i&e an initial acti&ity of 3.+ HCi? 1 Ci ,.7 E
B:.
A) .9 E B) 9. E C) 3., E D) ,.$ E ) $./ E Answer! A #ar!
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$/) What mass of 1/C (ha&in a half%life of 7,+ years) do you need to pro&ide a decay rate of (1 u 1.33+ E 1+%$7 ;) A) 1.7+ E 1+%1$ ; B) .,9 E 1+%1 ; C) ,.9/ E 1+%$+ ; D) 9.39 E 1+%1, ; Answer! A #ar! +<
$) 8ow many days are re:uired for a radioacti&e sample" with a half%life of .7 d and an initial acti&ity of 1.+7 E 1+ B:" to decay to an acti&ity of 1++ B:? A) 7 d B) /3 d C) 39 d D) , d Answer! A #ar! /1
$3) A hospital patient has been i&en some (half%life 9.+/ d) which decays at /.$ times the acceptable le&el for eposure to the eneral public. 8ow lon must the patient wait for the decay rate to reach the acceptable le&el? Assume that the material merely decays and is not ecreted by the body. A) 17 d B) 1$ d C) 9.+ d D) 7.$ d Answer! A #ar! ,1
$7) The material used in certain nuclear bombs is $,4u" which has a half%life of about $+"+++ years. 8ow lon must we wait for a buried stoc;pile of this substance to decay to /.+K of its oriinal $,4u mass? A) ,"+++ y B) 3/"+++ y C) /"+++ y D) 9++ y Answer! A #ar! 1
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$9) An air sample is contaminated with 1L" which has a half%life of $.+, min. Lne possible way to minimie its haard is to pass it throuh a lon pipe to allow it to decay inside the pipe until it can be safely released into the atmosphere. 5f the oyen mo&es at a speed of 1.1 m>s in the pipe" how lon must the pipe be for the sample to ha&e decayed to ,.+K of its oriinal acti&ity ust as it lea&es the pipe? A) 39+ m B) 9.+ m C) 7.+ m D) $.+ m Answer! A #ar! 1
$) Gutherfordium%$31 has a half%life of 1.+9 min. 8ow lon will it ta;e for a sample of rutherfordium to lose one%third of its nuclei? A) 1.+$ min B) 1.3$ min C) +.3,$ min D) $.7+ min ) ,.$/ min Answer! C #ar! 1
,+) A radioacti&e sample has a half%life of 1+ min. What fraction of the sample is left after /+ min? A) 1>$ B) 1>/ C) 1>9 D) 1>13 ) 1>,$ Answer! D #ar! ,
,1) *ermium%$, has a half%life of ,.++ d. A sample of fermium contains 7.,7 E lon will it ta;e for there to be only ,.,3 E
fermium nuclei in this sample?
A) $.7 d B) .9+ d C) 1,./ d D) 1.7 d ) 9.3 d Answer! C #ar!
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nuclei. 8ow
,$) 5n a laboratory accident a wor; area is contaminated with radioacti&e material. 8ealth physicists monitor the area durin a ,+%day period and" after correctin for the bac;round rate" obtain the data shown in the table. Time (days) Counts/min
+ 1+++
$ 9
3 7$7
11 7
1 ,3/
,+ $+$
The accident occurred at t +. They determine that it will not be safe for wor;ers to enter the area until the radioacti&ity le&el has dropped to 1,, counts per minute. Lf the choices listed below" which one is the earliest time that wor;ers could safely return? A) ,9 days B) // days C) + days D) ,$ days ) $/ days Answer! A #ar! 1
,,) The unstable isotope $,/Th decays by β emission with a half%life of $/. days. The initial decay rate of the sample was . E 1+1, B:. (1 u 1.33+ 1+%$7 ;) (a) What mass of $,/Th was initially present? (b) What is the decay rate after 39 days? Answer! (a) +.1$ (b) 1./ 1+1, B: #ar! 1
,/) An isotope of Tc ha&in a half%life of 3.+ h is used in bone scans. 5f a certain amount of this Tc is inected into the body" how lon does it ta;e for its initial decay rate to decrease BM K? A) +.+3+ h B) ,., h C) ,, h D) /+ h ) slihtly more than a month Answer! D #ar! 1
,) The radioacti&ity due to carbon%1/ measured in a piece of a wood from an ancient site was found to produce $+ counts per minute from a i&en sample" whereas the same amount of carbon from a piece of li&in wood produced 13+ counts per minute. The half%life of carbon%1/" a beta emitter" is 7,+ y. The ae of the artifact is closest to A) 7++ y B) 1$"+++ y C) 1"+++ y D) 17"+++ y ) $,"+++ y Answer! D #ar! 1 19 Copyriht 2 $+13 4earson ducation" 5nc.
,3) Carbon%1/ has a half%life of 7,+ y. A sample of wood has been reco&ered by an archaeoloist. The sample is sent to a laboratory" where it is determined that the acti&ity of the sample is +.1// B:>. By comparin this acti&ity with the acti&ity of li&in oranic matter" +.$,+ B:>" the scientist determines how old the wood sample is" or more precisely" when the tree that the sample came from died. 8ow old is the sample of wood? A) ,97+ y B) /$+ y C) /+ y D) $3,+ y ) $/+ y Answer! A #ar! 1
,7) -i&in matter has 1., E 1+%1+ K of its carbon in the form of 1/C which has a half%life of 7,+ y. A mammoth bone has a ,++% sample of carbon separated from it" and the sample is found to ha&e an acti&ity of $+ decays per second. 8ow old is the bone? A) 1"+++ y B) 1+"++ y C) 11"++ y D) 73++ y ) 3/++ y Answer! B #ar! 1
,9) An archaeoloist finds the 1/C in a sample of of material to be decayin at 1+7 counts per second. A modern 1.++% sample of the same material decays at 11 counts per second. The half%life of 1/C is 7,+ y. 8ow old is the sample? A) 1$"$++ y B) 9/3+ y C) $"1++ y D) 1$"3++ y Answer! A #ar! 13
,) An ancient roc; is found to contain /+Ar as" indicatin that of the /+= in the roc; has decayed since the roc; solidified. Any aron would ha&e boiled out of li:uid roc;. The half%life of /+= is 1.$ billion years. 8ow lon ao did the roc; solidify? A) $.3 billion years B) +.+ billion years C) 1.9 billion years D) +.,+ billion years Answer! A #ar! ,+
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/+) Today" the uranium found on arth contains +.7$+K $, (with a half%life of +.7++ billion years) and .$9K $,9 (with a half%life of /.+ billion years). At a time $.$+ billion years ao" what percent of the uranium on arth was $,9 (assumin that no other uranium isotopes were present)? A) .3K B) $.19K C) 3.$K D) 9.39K ) /.,K Answer! A #ar! 1
/1) 5n the nuclear reaction
B<
8e J
8 < '" which of the followin is the missin
nuclear product '? A)
*
B)
0
C)
C
D)
0
)
0
Answer! C #ar! 1
/$) 5n the nuclear reaction n<
J ' < $e%
n is a neutron and e% is an electron" and the neutrinos ha&e not been shown. Determine the atomic mass and atomic number of the missin nuclear product '" and write ' in the standard form. 5t is 0LT necessary to identify which atom ' is. Answer! A $," Z /"
'
#ar! 1
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/,) *or the missin product ' in the nuclear reaction neutron <
L J ' < alpha particle
determine the atomic mass and atomic number of '" and write ' in the standard form. 5t is 0LT necessary to identify which atom ' is. Answer! A 1," Z 3"
'
#ar! 1
//) *or the missin product ' in the reaction neutron <
J
Ba < ' < , neutrons
determine the atomic mass and atomic number of '" and write ' in the standard form. 5t is 0LT necessary to identify which atom ' is. Answer! A $" Z ,3"
'
#ar! 1
/) A proton stri;es an
L nucleus producin
* and another particle. What is the other
particle? A) a neutron B) an alpha particle C) a β % particle D) a β < particle ) a amma ray Answer! A #ar! 1
/3) 8ow much enery is released in the total fission of of The a&erae enery per fission is $++.+ @e#. (1 u ,1. @e#>c$ 1.33+ E 1+%$7 ;" 1 e# 1.3+ E 1+%1 I) A) 1.3 E 1+11 I B) ,. E 1+1, I C) 1.3 E 1+ I D) ,. E 1+1+ I Answer! A #ar! 3
$1 Copyriht 2 $+13 4earson ducation" 5nc.
/7) An ecited
N J
N nucleus underoes fission into two framents" as shown!
Ba <
=r
The followin atomic masses are ;nown! =r! 1.$3$7+ u Ba!1/,.$$9/ u N!
$,3.+/3, u
What is the reaction enery" in @e#" for this process? (1 u 1.33+ E 1+%$7 ; ,1. @e#>c$) A) 1+ @e# B) 13+ @e# C) 17+ @e# D) 19+ @e# ) 1+ @e# Answer! D #ar! 1
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/9) An ecited
N J
N nucleus underoes fission into two framents" as shown!
Ba <
=r
The followin atomic masses are ;nown! =r! 1.$3$7+ u Ba!1/,.$$9/ u N!
$,3.+/3, u
Assume" at a i&en instant" that the two fission framents are spherical" ust barely in contact" and carry spherically symmetric chare distributions. At that instant" what is the electrostatic interaction enery of the two framents" in @e#? (1 u 1.33+ E 1+%$7 ; ,1. @e#>c$" 1>/πε+ .+ E 1+ 0 N m$>C$) A) $,+ @e# B) $/+ @e# C) $+ @e# D) $3+ @e# ) $7+ @e# Answer! C #ar! 1
/) 5n the fission reaction
< neutron J
Ba <
=r < x neutrons" what is the number x
of neutrons produced? A) + B) / C) 1 D) , ) $ Answer! D #ar! 1
$, Copyriht 2 $+13 4earson ducation" 5nc.
+) When a neutron (n) collides with a uranium%$, nucleus it can induce a &ariety of fission reactions. Lne such reaction is
'e <
r < $n. 8ow much enery is released
in this reaction" i&en the followin mass &alues! 'e!
1,.$13$+ u
r ! ,.1,37 u ! $,.+/,$/ u n! 1.++933 u (1 u ,1.// @e#>c$) A) 19 @e# B) $+$ @e# C) ,$.3 @e# D) 3.7 @e# ) 9.3 @e# Answer! A #ar! 1
1) 5f a $.+%@e# neutron released in a fission reaction loses half of its enery in each moderator collision" how many collisions are needed to reduce its enery to (1>$) e#? A) 3 B) 19 C) $3 D) ,+ ) / Answer! C #ar! 1
$) Calculate the amount of enery that is released in the fusion reaction $8 < $8 J /8e" i&en the masses! $8! $.+1/1+$ u /8e! /.++$3+, u (1 u ,1. @e#>c$) A) $/ @e# B) 19 @e# C) 1, @e# D) 1$ @e# ) ,3 @e# Answer! A #ar! 1
$/ Copyriht 2 $+13 4earson ducation" 5nc.
,) The reaction $8 < $8 J? ,8 < 18 releases /.+, @e# of enery. 5f 1.+ ; of deuterium were to o throuh this reaction" how much enery would be produced? (1 e# 1.3+ E 1+%1 I" mdeuterium $.+1$ u" 1 u ,1. @e#>c$ 1.33+ E 1+%$7 ;) A) .7 E 1+7 I B) .7 E 1+1, I C) 1. E 1+7 I D) 1. E 1+1/ I ) 1. E 1+11 I Answer! B #ar! 1
/) Two deuterium nuclei"
8" fuse to produce a tritium nucleus"
8" and a hydroen nucleus. A
neutral deuterium atom has a mass of $.+1/1+$ uF a neutral tritium atom has a mass of ,.+13+/ uF a neutral hydroen atom has a mass of 1.++79$ uF a neutron has a mass of 1.++933 uF and a proton has a mass of 1.++7$73 u. 8ow much enery is released in the process? (1 u ,1.// @e#>c$) A) ,.+, @e# B) ,., @e# C) /.+, @e# D) /., @e# ) 3.9 @e# Answer! C #ar! 1
$ Copyriht 2 $+13 4earson ducation" 5nc.
) Consider the fusion reaction 8<
8<
8 J
8e <
8 <
n
The atomic masses are! 8!
$.+1/1+ u
8e! /.++$3+ u 8"
1.++79, u
n!
1.++933 u
What mass of deuterium fuel"
8" is used up in producin 9.$ E 1+1, I of enery by this
reaction? (1u 1.33+ E 1+%$7 ; ,1. @e#>c$) Answer! +.$/ ; #ar! 1
3) Two deuterium nuclei"
8" fuse to produce a helium nucleus"
8" and a neutron. A neutral
deuterium atom has a mass of $.+1/1+$ uF a neutral helium atom has a mass of ,.+13+,+ uF a neutral hydroen atom has a mass of 1.++79$ uF a neutron has a mass of 1.++933 uF and a proton has a mass of 1.++7$73 u. 8ow much enery is released in the process? (1 u ,1.// @e#>c$) A) ,.$7 @e# B) ,.7 @e# C) /.++ @e# D) /.+ @e# ) .39 @e# Answer! A #ar! 1
$3 Copyriht 2 $+13 4earson ducation" 5nc.
7) A 7+%; laboratory technician absorbs $. mI of +.+%@e# amma rays in a wor;day. 8ow many amma%ray photons does the technician absorb in a wor;day? A) ,.3 E 1+1+ B) ,.3 E 1+ C) ,.3 E 1+9 D) 1.+ E 1+ ) 1.+ E 1+9 Answer! A #ar! 1
9) The radioacti&e nuclei 3+Co is widely used in medical applications. 5t underoes beta decay" and the total enery of the decay process is $.9$ @e# per decay e&ent. The half%life of this nucleus is $7$ days. uppose that a patient is i&en a dose of 3. OCi of 3+Co. 5f all of this material decayed while in the patientPs body" what would be the total enery deposited there? (1 Ci ,.7+ E 1+1+ decays>s) A) 11 I B) 9.3 6I C) ,. I D) $/ I ) /.1 @I Answer! C #ar! 1
$7 Copyriht 2 $+13 4earson ducation" 5nc.