COMEDK2013PhysicsGravitation
A particle of mass m is kept at rest at a height 3 R from the surface of earth, where R is radius of earth and M is mass of earth. The minimum speed with which it should be projected, so that it does not return back, is ( g is acceleration due to gravity on the surface of earth)
Options
- A( G M 2 R )^ 1 / 2
- B( g R 4 )^ 1 / 2
- C( 2 g R )^ 1 / 2
- D( G M R )^ 1 / 2
Correct answer
A. ( G M 2 R )^ 1 / 2
Step-by-step solution
The escape velocity from earth's surface is given by aligned v_ e &= 2 G M R+h Given, h &=3 R v_ e &= 2 G M 4 R = G M 2 R aligned