Question

An object weighing 400N on the surface of earth. At what height from the surface of earth it's weight will become 100N?

Answer 1

Answer:

5.16 x 10^6 m = 5160000 m

Explanation:

Let x metres be that height from the surface

Weight on the surface = 400N

=> mass of the object = 40 kg ( taking g = 10 m/s^2 at the surface)

100 = GMm/x^2

=> x^2 = 6.67 x 10^-11 x 10^24 x 40 /100

=> x^2 = 6.67 x 10^12 x 4

=> x^2 = 26.68 x 10^12

=> x = root of 26.68 x 10^12

=> x = 5.16 x 10^6 m. (approx.)