# A pendulum bob of mass  connected to the end of an ideal string of length  is released from rest from horizontal position as shown in Fig. At the lowest point, the bob makes an elastic collision with a stationary block of mass 5 , which is kept on a frictionless surface. Mark out the correct statement(s) for the instant just after the impact a) Tension in the string is b) Tension is the string is c) The velocity of the block is d) The maximum height attained by the pendulum bob after impact is (measured from the lowest position)

## Question ID - 100615 :- A pendulum bob of mass  connected to the end of an ideal string of length  is released from rest from horizontal position as shown in Fig. At the lowest point, the bob makes an elastic collision with a stationary block of mass 5 , which is kept on a frictionless surface. Mark out the correct statement(s) for the instant just after the impact a) Tension in the string is b) Tension is the string is c) The velocity of the block is d) The maximum height attained by the pendulum bob after impact is (measured from the lowest position)

3537

(a,d)

The velocity of bob just before the impact is  along the horizontal direction

From momentum conservation,

From coefficient of restitution equation,

Solving above equations, we get

For tension in string,

Let the maximum height attained by the bob be , then

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