Q7.27 Prove the result that the velocity of translation of a rolling body (like a ring, disc,
cylinder or sphere) at the bottom of an inclined plane of a height is given by
using dynamical consideration (i.e. by consideration of forces and torques). Note is
the radius of gyration of the body about its symmetry axis, and is the radius of the
body. The body starts from rest at the top of the plane.
Consider the given situation :
The total energy when the object is at the top (potential energy) = mgh.
Energy when the object is at the bottom of the plane :
Put and , we get :
By the law of conservation of energy we can write :
or
.