A kid of mass M stands at the edge of a platform of radius R which can be freely rotated about its axis. The moment of inerti of the platform is I . The system is at rest when a friend throws as ball of mas mand the kid cathces it. If the velocity of the ball is v horiontally along the tangent to the edge of the platform when it was caught by the kid find the angular speed of the platform after the event.

A kid of mass M stands at the edge of a platform of radius R which can

1.	A kid of mass M stands at the edge of a platform of radius R which can be freely rotated about its axis. The moment of inerti of the platform is I . The system is at rest when a friend throws as ball of mas mand the kid cathces it. If the velocity of the ball is v horiontally along the tangent to the edge of the platform when it was caught by the kid find the angular speed of the platform after the event.
Answer» Correct Answer - B A kid of mass M stands at tehedge of the platform of a raduis R which has a moment of inertia I. S ball thrown to him and with horizontal velocity of the ball -v when we catches it. Therefoe if we take the total bodies as a system `mvR={1+(M+m)R^2}omega` The moment of inerti aofkid adn ball about the axis=`(M+m)R^2` `rarr omega=(mvR)/(1+(M+m)R^2)`

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