The radius and mass of Earth are `R` and `M`. The acceleration due to gravity at its surface is `g`. Calculate the work required in raising a body of mass `m` to a height `h` from the surface of earth.

Explanation

Work done = change in potential energy
`W = - (GMm)/((R + h)) - (-(GMm)/(R ))`
`= GMm [(1)/(R ) - (1)/(R + h)] = (GMmh)/(R (R + h))`
`= (gR^(2)mh)/(R(R + h)) = (mgh)/((1 + h//R)) [:' GM = gR^(2)]`