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A perso is standing on a rotating platfo...

A perso is standing on a rotating platform wit his arms outstretched.Suddelny,he folds his hands near to his body.which of the following is correct?

A

The angular velocity decreases

B

His M.I. decreases

C

The angular velocity remains constant

D

Angular momentum increases.

Text Solution

Verified by Experts

The correct Answer is:
B
`I=Mr^2` on lowering his hands, r decreases, in turn moment of inertia decreases.
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