PYQ NEET- Rotational Motion About A Fixed Axis

2019:

The moment of inertia of a rotating body is given by:

I = ½MR²

Where:

• I is the moment of inertia of the body
• M is the mass of the body
• R is the radius of the body

In the first case, the moment of inertia of the wheel is:

I_1 = MR^2

In the second case, the moment of inertia of the wheel is:

I_2 = (M/2)R^2 + (M/2)R^2 = MR^2

Therefore, the ratio of the moment of inertia of the wheel in the two cases is:

I_1 / I_2 = 1

2018:

A solid sphere, a hollow sphere and a ring are released from the top of an inclined plane. The solid sphere reaches the bottom first because it has the least moment of inertia. The moment of inertia of a solid sphere is given by:

I = 2/5MR^2