Question

Which option is correct if $I_1,I_2$ and $I_3$ are moments of inertia of solid sphere, hollow sphere and a ring of same mass and radius,

• A. $I_1>I_2>I_3$
• B. $I_3>I_2>I_1$
• C. $I_2>I_1>I_3$
• D. $I_2>I_3>I_1$

Answer 1

Answer: (B)

Let $m$ be the mass and $r$ be the radius of the bodies, then the moment of inertia of solid sphere will be,
$I_1=\frac{2}{5}m{r}^2$
The moment of inertia of hollow sphere will be,
$I_2=\frac{2}{3}m{r}^2$
The moment of inertia of the ring is given by,
$I_3=m{r}^2$
Therefore, $I_3>I_2>I_1$ .