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A ballet dancer spins about a vertical a...

A ballet dancer spins about a vertical axis at 60 rpm with his arms closed. Now he stretches his arms such that M.I. Increases by `50%`. The new speed of revolution is

A

80 rpm

B

40 rpm

C

90 rpm

D

30 rpm

Text Solution

Verified by Experts

The correct Answer is:
B
`I_(1)omega_(1)=I_(2)omega_(2), I_(1)n_(1)=I_(2)n_(2)`
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