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A disc is free to rotate about a smooth ...

A disc is free to rotate about a smooth horizontal axis passing through its centre of mass. A particle is fixed at the top of the disc. A slight push is given to the disc and it starts rotating. During the process.

A

only mechanical energy is conserved

B

only angular momentum (about the axis of rotation) is conserved

C

both mechanical energy and angular momentum are conserved

D

Neither the mechanical energy nor the angular momentum are conserved.

Text Solution

Verified by Experts

The correct Answer is:
A
Angular momentum will not remain conserved due to a torque of weight of particle about axis of rotation.
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