A dancer girl is rotating over a turntable with her arms out stretched. If she lowers...

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Answer 1

Answer #1

Angular momentum, L = Iω where I is the moment of inertia and ω is the angular speed.

According to law of conservation of angular momentum, Iω = a constant when net external torque is zero.

Hence, a change in moment of inertia results in a change in the angular speed.

When a dancer girl lowers her arms, her moment of inertia is decreased and thus her angular speed is increased.

** her spinning rate increases because her moment of inertia decreases.

Answer 2

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