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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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HC VERMA-ROTATIONAL MECHANICS-Exercises
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  2. A kid of mass M stands at the edge of a platform of radius R which can...

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  3. Suppose the platform of the previous problem is brought to rest with t...

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  4. Suppose the platform with the kid in the previous problem is rotting i...

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  5. A uniform rod of mass m and length l is struck at an end by a force F ...

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  6. A uniform rod of length L lies on a smooth horizontal table. A particl...

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  7. Suppose the particle of the previous problem has a mass m and a speed ...

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  8. Two small bals A and B, each of mass m, are joined rigidlyl by a light...

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  9. Two small balls A and B each of mass m, are joined rigidly to the end...

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  10. Suppose the rod with the balls A and B of theprevious problem is clamp...

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  11. Two blocks of masses 400 g and 200 g are connected through a light str...

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  12. The pulley shown in figure has a radius of 20 cm and moment of inertia...

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  13. A metre stick is is held verticaly with one end on a rough horizontal ...

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  14. A metre stick weighing 240 g is pivoted at its upper end in such a way...

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  15. A uniform rod pivoted at its upper end hangs vertically. It is displac...

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  16. A cylinder rolls on a horizontal plane surface. If the speed of the ce...

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  17. A sphere of mass m rolls on a plane surface. Find its kinetic energy a...

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  18. A string is wrapped over the edge a uniform disc and the free end is f...

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  19. A small spherical ball is released from a point at a height h on a rou...

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  20. A small disc is set rolling with a speed v on the horizontal part of t...

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