8.15 A body weighs 63 N on the surface of the earth. What is the gravitational force on it due to the earth at a height equal to half the radius of the earth?

Given,
Weight of the body, W = 63 N
Acceleration due to gravity at height h from the Earth's surface is given by the relation:
g'=g1+hR2
For,h=R2
g'=g1+R/2R2=49g
Therefore,theweightofthebody,
W=mg'
=m×49g
=49×63g=28N