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A ballet dancer, dancing on a smooth flo...

A ballet dancer, dancing on a smooth floor is spinning about a vertical axis with her arms folded with angular velocity of `20 rad//s`. When the stretches her arms fully, the spinning speed decrease in `10 rad//s`. If `I` is the initial moment of inertia of the dancer, the new moment of inertia is.

A

2I

B

3I

C

`I//2`

D

I//3`

Text Solution

Verified by Experts

The correct Answer is:
A
`Ixx20=I.xx10impliesI.=2I`
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