Question

Find the gravitational force on a body of man 40 kg situated on the surface of the earth; if radius of earth (R) = 6400 km and mass of earth (M) = 6 x 10²⁴ kg.

Answer 1

Mass of a body (m) = 40 kg Mass of earth (M) = 6 x 10²⁴ kg

Radius of earth (R) = 6400 km = 6400 x 10³ = 6.4 x 10⁶ m

Gravitational constant (G) = 6.67 x 10^-11  Nm²/kg²

According to Newton’s gravitational law,