Rolling: Consider a uniform solid sphere of radius R and mass M rolling without slipping. Which form of its kinetic energy is larger, translational or rotational?
A) Its translational kinetic energy is larger than its rotational kinetic energy.
B) Its rotational kinetic energy is larger than its translational kinetic energy.
C) Both forms of energy are equal.
D) You need to know the speed of the sphere to tell.

Question

Quizplus · Accepted Answer

For a rolling sphere, translational kinetic energy is (1/2)Mv^2 and rotational kinetic energy is (1/2)Iω^2. For a solid sphere, I = (2/5)MR^2 and ω = v/R, so rotational kinetic energy becomes (1/5)Mv^2. Thus, translational kinetic energy is larger.

Rolling: Consider a Uniform Solid Sphere of Radius R and Mass