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If a person standing on a rotating disc ...

If a person standing on a rotating disc stretches out his hands, the angular speed will

A

increases

B

decreases

C

remain same

D

none of these

Text Solution

Verified by Experts

The correct Answer is:
B
Which his hands are stretched radius of gyration (r) is increased
Angular momentum,
`L=I omega`
`L=mr^(2)omega`
As radius of gyration (r) is increased, angular speed `(omega)` will be decreased. Since angular momentum (L) is conserved (remains constant).
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