question_answer

A rocket is launched straight up from the surface of earth. When its altitude is one fourth of the radius of earth, its fuel runs out and therefore it coasts. The minimum velocity which the rocket should have when it starts to coast if it is to escape from the gravitational pull of the earth is approximately,

A) \[1\,\,km\,\,{{s}^{-1}}\]                       

B) \[6\,\,km\,\,{{s}^{-1}}\]

C) \[10\,\,km\,\,\,{{s}^{-1}}\]                    

D) \[15\,\,km\,\,{{s}^{-1}}\]