A particle is thrown with escape velocity ve =11.2km/s from the surface of earth. Its velocity at height 3R = 19200 Km is:
9.25 km/s
5.6 km/s
11.2 km/s
4.3 km/s
By using COME −GMmR+12mve2=−GMm4R+12mv2⇒v=5.6km/s