What is the force of gravity on a body of mass 150 kg lying on the surface of the earth? (Mass of earth = 6×10²⁴ kg; Radius of earth = 6.4× 10⁶ m; G = 6.7×10^-11 Nm²/kg²)

Explain why, if a stone held in out hand is released, it falls towards the earth.

Calculate the force of gravitation between two objects of masses 50 kg and

120 kg respectively kept at a distance of 10 m from one another. (Gravitational constant, G = 6.7 × 10^-11 Nm² Kg^-2)

The mass of sun is 2 × 10³⁰ kg and the mass of earth is 6×10²⁴ kg. If the average distance between the sun and the earth be 1.5×10⁸ km, calculate the force of gravitation between them.

A piece of stone is thrown vertically upwards. It reaches the maximum height in 3 seconds. If the acceleration of the stone be 9.8 m/s² directed towards the ground, calculate the initial velocity of the stone with which it is thrown upwards.