Question

While the turntable is being accelerated, the person suddenly extends her legs. What happens to the turntable?

A) The turntable accelerates more rapidly.
B) The turntable decelerates.
C) The turntable maintains its acceleration.
D) The turntable comes to a sudden stop

Answer 1

When a person extends her legs on a turntable, the moment of inertia increases, necessitating a decrease in angular velocity to conserve angular momentum, hence the turntable decelerates. The correct answer to the question is: B) The turntable decelerates.

Step-by-step explanation:

When a person extends her legs while spinning on a turntable, it affects the turntable's rotation due to the principle of conservation of angular momentum.

In this scenario, angular momentum must be conserved because no external torque is acting on the system. Angular momentum is the product of the moment of inertia and the angular velocity. When the person extends her legs, the moment of inertia increases because the mass distribution of her body is farther from the axis of rotation.

To conserve angular momentum, the angular velocity of the system must decrease, causing the turntable to decelerate.

Therefore, the correct answer to the question is: B) The turntable decelerates.