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 ?

Explanation

We are given, W= 63N
Height, h= R/2
We are to calculate: Gravitational force at height R/2.
Using the relation
`g_(h)= g [(R^(2))/((R+h)^(2))]`
`rArr mg_(h)= mg (R^(2))/((R+h)^(2)) = (63 xx R^(2))/((R+ (R)/(2))^(2))= (63 xx R^(2))/((9R^(2))/(4))= 28N`