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A person sitting firmly over a rotating ...

A person sitting firmly over a rotating stool has his arms stretched. If he folds his arms, his angular momentum about the axis of the rotation :

A

Increases

B

Decreases

C

Remains unchanged

D

Doubles.

Text Solution

Verified by Experts

The correct Answer is:
C
When the person fold his arm then torque is zero. Since `tau=(dL)/(dt)=0impliesL` = constant
i.e. angular momentum remains const.
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