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A ballot dancer is rotating about his ow...

A ballot dancer is rotating about his own vertical axis on smooth horizontal floor with a time period `0.5 sec`. The dancer flods himself close to his axis of rotation due to which his radius of gyration decreases by `20%`, then his new time period is

A

0.1 sec

B

0.25 sec

C

0.32 sec

D

0.4 sec

Text Solution

Verified by Experts

The correct Answer is:
C
` I_(1)omega_(1) = I_(2)omega_(2) , mK_(1)^(2)xx (2pi)/(T_(1)) = mK_(2)^(2) xx (2pi)/(T_(2))`
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  18. A ball rolls without slipping. The radius of gyration of the ball abou...

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  19. A wheel is rolling uniformly along a level road without slipping...

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