A woman sits on a spinning piano stool with her arms folded.When she extends her arms,which of the following occurs?
A)She increases her moment of inertia,thereby increasing her angular speed.
B)She increases her moment of inertia,thereby decreasing her angular speed.
C)She decreases her moment of inertia,thereby increasing her angular speed.
D)She decreases her moment of inertia,thereby decreasing her angular speed.
E)Both her moment of inertia and her angular speed remain constant.

Question

Quizplus · Accepted Answer

When the woman extends her arms, she increases her moment of inertia, which is the measure of an object's resistance to change in its rotational motion. As a result, her angular speed decreases to conserve angular momentum, which is equal to the product of moment of inertia and angular speed. This conservation law implies that when moment of inertia increases, angular speed decreases and vice versa.

A Woman Sits on a Spinning Piano Stool with Her