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AIIMS2005PhysicsGravitation

The condition for a uniform spherical mass m of radius r to be a black hole is [G= gravitational constant and g= acceleration due to gravity]

Options

  1. A( 2 G m r )^ 1 / 2 c
  2. B( 2 g m r )^ 1 / 2 =c
  3. C( 2 G m r )^ 1 / 2 c
  4. D( g m r )^ 1 / 2 c

Correct answer

C. ( 2 G m r )^ 1 / 2 c

Step-by-step solution

The criterion for a star to be black hole is G M c^2 R 1 2 or, 2 G M R c .

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