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A ballet dancer is rotating about his ow...

A ballet dancer is rotating about his own vertical axis at an angular velocity `100 rpm` on smooth horizontal floor. The ballet dancer folds himself close to his axis of rotation by which is moment of inertia decreases to half of initial moment of inertia then his final angular velocity is

A

50 rpm

B

100 rpm

C

150 rpm

D

200 rpm

Text Solution

Verified by Experts

The correct Answer is:
D
`I_(1)omega_(1)=I_(2)omega_(2),I_(1)n_(1)=I_(2)n_(2)impliesn_(2)=200` rpm
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