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At any instant, a rolling body may be co...

At any instant, a rolling body may be considered to be in pure rotation about an axis through the point of contact. This axis is translating forward with speed

A

equal to centre of mass

B

zero

C

twice of centre of mass

D

None of these

Text Solution

Verified by Experts

The correct Answer is:
A
Since, in this case instantaneous axis of rotation is always below the centre of mass. This is possible only when point of contact moves with a velocity equal to centre of mass.
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a) show that the energy of a rolling body which is not slipping is equivalent to that of pure rotatioin with the same angular speed about an axis through the point of contact of the rolling body. b) Show that the angular momentum of a body of mass M which is rolling without slippint about any point is equal to its angular momentum about its center plus the moment of momentum of a particle of the same mass M concentrated at its center and moving with the speed of the center of the mass of the body about the same point

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Knowledge Check

  • For a rotating body about fixed axis ,

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