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A boy stands on a freely rotating platfo...

A boy stands on a freely rotating platform with his arms extended. His rotation speed is 0.3 rev/s, when he draws in, his speed increases to 0.5 rev/s, then the ratio of his moment of inertia in these two cases will be

A

`3 : 5`

B

`5 : 3`

C

`9 : 25`

D

`25 : 9`

Text Solution

Verified by Experts

The correct Answer is:
B
`I_(1)omega_(1)=I_(2)omega_(2)`
`KE_(2)=(1)/(2)I omega^(2)`
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