82. We make use of Table 11-2(e) as well as the parallel-axis theorem, Eq. 11-27, where needed. We use
(as a subscript) to refer to the long rodands to refer to the short rod.
(a) The rotational inertia is
I = I
s
+ I
=
1
12
m
s
L
2
s
+
1
3
m
L
2
= 0.019 kg
·m
2
.
(b) We note that the center of the short rodis a distance of h = 0.25 m from the axis. The rotational
inertia is
I = I
s
+ I
=
1
12
m
s
L
2
s
+ m
s
h
2
+
1
12
m
L
2
which again yields I = 0.019 kg
·m
2
.