Question

Three bodies, a ring, a solid cylinder and a solid sphere roll down the same inclinedplane without slipping. They start from rest. The radius of the bodies are identical.Which body has the greatest rotational kinetic energy while reaching the bottom ofthe inclined plane?

Answer 1

We know that energy of a rolling body is conserved. So,

Potential energy lost by the body =  kinetic energy gained

As the body starts from rest, the kinetic energy gained will be equal to the final kinetic energy of the body.