Q: In order to shift a body of mass *m* from a circular orbit of radius 3R to a higher orbit of radius 5R around the earth, the work done is

(a) $ \displaystyle \frac{3 G M m}{5 R} $

(b) $ \displaystyle \frac{ G M m}{2 R} $

(c) $ \displaystyle \frac{2 G M m}{15 R} $

(d) $ \displaystyle \frac{ G M m}{5 R} $

Ans:(c)