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JEE Main2002PhysicsGravitationActual

The kinetic energy needed to project a body of mass m from the earth surface (radius R ) to infinity is

Options

  1. AmgR / 2
  2. B2 mgR
  3. CmgR
  4. DmgR / 4

Correct answer

C. mgR

Step-by-step solution

KE = 1 2 mv _ esc ^2= 1 2 ~m ( 2 gR )^2= mgR

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