The weight of a body on the surface of the earth is 100 N . The gravitational force on it when taken at a height, from the surface of earth, equal to one-fourth the radius of the earth is:

Step-by-step solution

The acceleration due to gravity changes as one goes to a height from the surface of the earth. Let the new acceleration due to gravity be g ' . The formula for acceleration due to gravity at a height is given by g ' = g R 2 R + h 2 The weight of the body on surface is W = m g = 100   N The weight at the given height is W = m g ' . ⇒ W ' = 100 × R 2 R + R 4 2 ⇒ W ' = 100 × R 2 25 R 2 16 = 64   N