An Ice Skater Doing a Spin Pulls in Her Arms

Multiple Choice

An ice skater doing a spin pulls in her arms, decreasing her moment of inertia by a factor of two. How does her angular speed changes?

A) It is reduced by a factor of two.
B) It is reduced by a factor of four.
C) It increases by a factor of two.
D) It increases by a factor of four.
E) It doesn't change.