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A man standing on a platform holds weigh...

A man standing on a platform holds weights in his outstretched arms. The system is rotated about a central vertical axis. If the man now pulls the weights inwards close to his body then

A

the angular velocity of the system will increase

B

the angular momentum of the system will increase

C

the kinetic energy of the system will increase

D

he will have to expend some energy to draw the weights in

Text Solution

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The correct Answer is:
A, C, D
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