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Suppose the platform of the previous pro...

Suppose the platform of the previous problem is brought to rest with the ball in tehhad of the kid standin on the rim. The kid throuws the ball horizontaly to his friend in a direction tangentiasl to the rim with a speed v as seen by his friend. Find the angular velocity wilth which the platform will start rotating.

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The correct Answer is:
B
Initial angular momentum =fiN/Al angular momentum (the total externla torque =0)
Initial angular momentum`=mVR(m-mass of the ball V=velocity of the ball )
(tangetial velocity)`
Therefore angular momentum
`=Iomega+MR^2omega`
`rarr omega=(mvR)/(1+MR^2)`
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