The mass of the earth is 6 x 1024 kg and that of the moon is 7.4 x 1022 kg. If the distance between the earth and the moon be 3.84 x 105 km, calculate the force exerted by the earth on the moon. The value of G = 6.7 x 10–11 Nm2 kg–2.
State Newton's universal law of gravitation. Hence define universal gravitational constant. Give the value of G.
Compare the gravitational forces exerted by the sun and the moon on the earth. Which exerts a greater force and by how many times?
Suppose that the two giant planets of the solar system, Jupiter and Saturn, are in the same line as seen from the earth. It happens occasionally that some planets appear in the same line from the earth. Find the total gravitational force due to them on a person of mass 50 kg on the earth. Compare this with the force of gravity on the same person. Could the force due to planets be important?
How did Newton guess the inverse square rule obeyed by the gravitational force?
