The universal law of gravitation :
The universal law of ’gravitation states that every body in the universe attracts other body with a force which is directly proportional to the product of their masses and inversely proportional to the square of the distance between them.
Let two bodies of masses M and M be separated by a distance of ’d’. Then the force of gravitation between them
G is a proportionality constant, called universal gravitational constant.
The value of G = 6.67 × 10-11 Nm2kg-2