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

Weight of the body `="mg" = 63"N"`
At height h, the value of `g` is given by
`g^(1) = (gR^2)/( (R + h)^2) = (g R^2)/( (R + R//2)^2) = 4//9g`
Gravitational force on body at height h is
`F = "mg"^(1) = m xx (4)/(9) g = (4)/(9) "mg"`
`= (4)/(9) xx 63 = 28N`