A small uniform disk and a small uniform sphere are released simultaneously at the top of a high inclined plane,and they roll down without slipping.Which one will reach the bottom first?
A)the one of smallest diameter
B)the one of greatest mass
C)the disk
D)the sphere
E)They will reach the bottom at the same time.

Question

Quizplus · Accepted Answer

Both the disk and the sphere have the same potential energy at the top of the inclined plane due to the same height and mass. However, the sphere has a larger moment of inertia than the disk, which means that it will have a greater rotational inertia and slower acceleration down the inclined plane. Therefore, the disk will reach the bottom before the sphere does.

A Small Uniform Disk and a Small Uniform Sphere Are