Two bodies have their moments of inertia I and 2I respectively about their axis of rotation. If their kinetic energies of rotation are equal, their angular velocity will be in the ratio

A drum of radius R and mass M, rolls down without slipping along an inclined plane of angle $$\theta $$. The frictional force

The ratio of the radii of gyration of a circular disc about a tangential axis in the plane of the disc and of a circular ring of the same radius about a tangential axes in the plane of the ring is

A round disc of moment of inertia $$I$$₂ about its axis perpendicular to its plane and passing through its centre is placed over another disc of moment of inertia $$I$$₁ rotating with an angular velocity $$\omega $$ about the same axis. The final angular velocity of the combination of discs is