Two balls, one of radius R and mass M, the other of radius 2R and mass 8M, roll down an incline. They start together from rest at the top of the incline. Which one will reach the bottom of the incline first?
A) The small sphere
B) Both reach the bottom together.
C) The large sphere
D) It depends on the height of the incline.
E) It depends on the length of the inclined surface.

Question

Quizplus · Accepted Answer

Both spheres will reach the bottom together because the acceleration of a rolling object down an incline depends only on the shape of the object and not on its size or mass. Both spheres are solid and will have the same acceleration.

Two Balls, One of Radius R and Mass M, the Other