Question

A body weighs 63N on the surface of the earth. What is the weight of the body at a height equal to half the radius of the earth?

Answer 1

weight =force which is proportional to 1/d^2
when the body is at a height =half radius
then d becomes from 1 to 1.5, so weight=1/(1.5 d)^2=1/2.25d^2=1/2.25×63N=28N