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 conservedB. only angular momentum (about the axis of rotation) is conservedC. both mechanical energy and angular momentum are conservedD. Neither the mechanical energy nor the angular momentum are conserved.

A disc is free to rotate about a smooth horizontal axis passing throug

1.	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 conservedB. only angular momentum (about the axis of rotation) is conservedC. both mechanical energy and angular momentum are conservedD. Neither the mechanical energy nor the angular momentum are conserved.
Answer» Correct Answer - A Angular momentum will not remain conserved due to a torque of weight of particle about axis of rotation.

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