Nuclear Physicsand Radioactivity
Problemi
(a) For each of the four radioactive decayslisted below, write the decay reaction and
identi$ the daughter in the form jX .
^il p, ----^?.,7
9 * | Heoo7
----*
e
+
c.,
Nr
-?
l;
93
crdecayof 'zlfPu
B-decayof ffNi
p* decayof ]lNa
lit"'--
y decayof 'z3rloTh-
iiNe".3re-"3o
+K
1'Jtn.----* 1t'.11b
(b) The numberof radioactivenuclei presentat the startof an experimentis 4.60 x 101s.
The numberpresenttwenty dayslater is 8.14 x 1014.What is the half-life (in days)ofthe
nuclei?
^t
N -- N'.
N,= 4'aorlo't
f..l= 8'"14*to''
N/
/N"
I= Eo"r."o
{V:
-^L
-a2
-h -l"'e"re4c'u \1 ',''"- W'@ a"dfu\a! !4zt
dbP" sryafue^:
% )xfuA At"
ln e^ = x
^:
- 4N4J
: --0" (I#**"),/rr*
= o.ozt"t"do
t
Vt
x= ")9)-=/\
/ q?
T,/*
-i1,.= O:E>=
9"61)
X
O,ost"t")o,pl
---olll/"= 8.o.t xa
Problem2
What is the averagebinding energyper nucleon(in MeV/nucleon)of the 1160
nucleus?
Usethe following masses(in atomicmassunits):
massof 0-16 atom: 15.9949146
u
np: 1.0072765
u
m'': 1.0086649
u
m":0.0005486u
.
b ^ N , D u r r\; b)x\t^/w
)x\r^@
"Wi
\,/ ^,
AI
c' pa-!4,
h^9 = -- (Lat"r)
6
/f, rq ra ]&ls N1,!4
(uP"'A ^""t-),ue ^* V**', om o-F^.^z1rn'orula
"}oe-'t"a)
P\'}{rzjt'^A
nu+'\"n") -bu,q Uto cc"'o'aa
Apfr\^ r/u"\ ,iF, ,trilr4 dtfu
\Wl
;{
Arcr = (rrr* ftrnr [e.)- n,b",r
lb ^
s
------" 8 -0".,1.,-- y 8.r.,*r.rUzr.a.)*.A
T &^fr'-ru
r suu)f - I 5,qq1il 4bu
u) -rI (o,ooo5
A r'.r= f f 1 t.oorrruBu ) + g (r,ms6t,1Q
Arr = O,]3?Oo51q
TW
tl,,ry.rrr&!*)"!Dbn
b+,il^Z ,*'4*
oarq ya" fu
l )^*
gr= 9 Zt.1q4 y\ev/u
E u= ( t.) ct = Co"ll?posT.r) (aar'aaaNev/a)
Eu = lE.?"orl.4.V
W