KE of Alpha Particle.pdf

YouTube Lecture # 57

1. 1


How much kinetic
energy must an alpha
particle have before its
distance of closest
approach to a gold
nucleus is equal to the
nuclear radius (7.0 ×
10
−15
m)?

HELPING TOOLS
No.1

OR

OR


No.2

2. 2


Atomic number of gold
(Aurum/Au) is 79

&
Alpha particle is identical to a
helium-4 nucleus with electric
charge +2e

No.3

3. 3



No.4


No.5



No.6

4. 4



No.7

No.8

No.9

5. 5




No.10 2 19 2
12
0
12 2
38
2
26
(1.602 10 )
4
4 3.14 8.85 10
2.57 10
111.156 10
2.57
111.156 10
e X C
F
X X X
m
X C m
XF
Cm
XF

−
−
=
=
=

6. 6
2
26
26
26 18
8
9
0.023121 10
0.023121 10
0.023121 10 6.24 10
0.14427504 10 .
1.4427504 10 .
1.4427504 .
Cm
X
C
Volt
X CmVolt
X X X eVXm
X eV m
X eV m
eV nm
−
−
−
−
−
=
=
=
=
=
=

Solution 22
00
2
0
We know that distance of
closest approach is given by
11
44
4
2 79
1.440 .
7.0
32.503
zZe zZe
dK
Kd
e zZ
KX
d
X
MeV fmX
fm
MeV
 

=  =
=
=
=