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Most Important Selected Qs for JEE AdvancedPhysicsLaws of Motion

The figure shows a block of mass M=2 m having a spherical smooth cavity of radius R placed on a smooth horizontal surface. There is a small ball of mass m moving at an instant vertically downward with a velocity v with respect to the block. At this instant :

Options

  1. AThe normal reaction on the ball by the block is mv ^2 R
  2. BThe normal reaction on the ball by the block is 2 3 m v^2 R
  3. CThe acceleration of the block with respect to the ground is v^2 3 R
  4. DThe acceleration of the block with respect to the ground is v^2 2 R

Correct answer

C. The acceleration of the block with respect to the ground is v^2 3 R

Step-by-step solution

Let the normal force between the block and the ball be N . For the block, from Newton's II ^ nd law, we have N = Ma =2 ma For ball (with respect to the block), from Newton's II ^ nd law, we have N+m a= m v^2 R Solve the two equations.

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