150
DOC.
4
KINETIC THEORY LECTURE NOTES
c2
=
c\
+
c\
-
2c1c2cos5
dZ12
=
n2na2crdK
sin 9
do d9
4
n
n
Zl2
~
n2na
4n
3=0
(a=0~2n
x
^/(c2
+ c\
-
2ctc2 cos
9)
sin
9
dod9
n2nr
1
2
(ci
+
c2
~
2clc2cos9)3'2
n
2
2cjc2 3
0
J
(Ci+C2)3-(C!-C2)
6c\c2
+
2c\
Z12
=
n2ji(Tz[c1
+-^1c2
Zn
=n1nsii^c1
[p. 5]
We
obtain the
mean
free
path
by dividing
the
velocity
c1
of
the molecule
by
the number
of
collisions
per
second.
1
r2
m
ky
~
CJ1
c2
Zy2
+
%!!
4
1
+
^
ci m2
-tiyns2y
+
n2no2
3 cf
1+^m-y3
If
only
one
kind
of
molecule
is present,
we get
X
=
1
4
2
-nns
3