Question

One solid sphere A and another hollow sphere B are of same mass and same outer radii. Their moment of inertia abut their diameters are respectively IA and IB such that:

• A. Ia = Ib
• B. Ia > Ib
• C. Ia < Ib
• D. Ia / Ib = da / db. Where $d _ { A }$and $d _ { B }$are the density of the sphere.

Answer 1

Answer: (C)

Ia < Ib

Answer 2

If the mass and radius are equal then moment of inertia of hollow sphere will be more than that of solid sphere.

$I _ { A } = I _ { \mathrm { Bksl } } = \frac { 2 } { 5 } M R ^ { 2 } = 0.4 M R ^ { 2 }$

$\therefore$ $I _ { A } < I _ { B }$