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BITSAT2024PhysicsGravitationActual

A body which is initially at rest at a height R above the surface of the Earth of radius R, falls freely towards the Earth, then its velocity on reaching the surface of the Earth is

Options

  1. A(2 g R)
  2. B(g R)
  3. C3 2 g R
  4. D(4 g R)

Correct answer

B. (g R)

Step-by-step solution

Increase in kinetic energy = Decrease in potential energy aligned & 1 2 m v^2= m g R 1+ R R = m g R 2 ( U= m g h 1+ h R , h=R ) & m v^2=m g R v= g R aligned

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