A solid sphere, a hollow sphere and a disc, all having same mass and radius, are placed at the top of an inclined plane and released. The friction coefficients between the objects and the incline are same and not sufficient to allow pure rolling. Least time will be taken in reaching the bottom by

Options

A. th solid sphere
B. the hollow sphere
C. the disc
D. all will take the same time

Answer

D

Explanation

Since linear acceleration is same for all `(a=Mgsintheta-mumgcostheta)` as they have same mass `M` and same `mu`.
Hence all will reach the bottom simultaneously.