Define the moment of inertia of a ’rigid body and write its SI unit.

How does the moment of inertia of a body change with temperature?

If the moment of inertia of a body rotating about an axis is increased, state whether its angular velocity increases or decreases when no external torque acts on the body.

State parallel -axes theorem of moment of inertia. The moment of inertia of a circular ring about its diameter is (1)/(2) MR^(2) . Calculate the moment of inertia of the ring about its tangent lying in its plane.

If the moment of inertia of a sphere of mass M and radius R about any diameter is m MR^2 , then, what will be its moment of inertia about any tangent?

Statement I : The mass of a body cannot be considered to be concentrated at the centre of mass of the body for the purpose of computing its moment of inertia. Statement II : For then the moment of inertia of every body about an axis passing through its centre of mass would be zero.

Define the Activity of a radioactive sample. Write its S.I. unit. A radioactive sample has activity of 10000 disintegrations per second (dps) after 20 hours. After next 10 hours its Activity reduces to 5000 dps. Find out its half-life and initial activity.