State the universal law of gravitation and derive its mathematical expression .

Explanation

This law states that every other particle of matter in this universe attracts every other particle with a force. This force is directly proportional to the product of their masses and inversely proportional to the square of the distance between the centres of there masses. The direction of the force acts along the line joining the masses. Derivation: Let m, and m, be the masses of two bodies A and B placed at r metre apart in space.
ForceF `propM_(1)xx m_(2) F prop (1)/(r^(2)`
On combining the above two expressions
`F prop(m_(1)xxM_(2))/(r^(s)),F=(Gm_(1)xxm_(2))/(r^(2))`
Where G is the universal gravitational constant. Its value is SI unit is `6.674 xx 10^(-11) Nm^(2)kg^(-2)`