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 beA. `3 : 5`B. `5 : 3`C. `9 : 25`D. `25 : 9`

A boy stands on a freely rotating platform with his arms extended. His

1.	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 beA. `3 : 5`B. `5 : 3`C. `9 : 25`D. `25 : 9`
Answer» Correct Answer - B `I_(1)omega_(1)=I_(2)omega_(2)` `KE_(2)=(1)/(2)I omega^(2)`

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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 beA. `3 : 5`B. `5 : 3`C. `9 : 25`D. `25 : 9`

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