A spinning ice skater on extremely smooth ice is able to control the rate at which she rotates by pulling in her arms.Which of the following statements are true about the skater during this process? (There could be more than one correct choice. )
A)Her angular momentum remains constant.
B)Her moment of inertia remains constant.
C)Her kinetic energy remains constant.
D)She is subject to a constant non-zero torque.

Question

Quizplus · Accepted Answer

CWhen the skater pulls in her arms, she reduces her moment of inertia and spins faster to conserve angular momentum (A), as no external torques act on her. The kinetic energy remains constant (C) because the work done is internal and does not add or remove energy from the system.

A Spinning Ice Skater on Extremely Smooth Ice Is Able