Question

state law of gravitation

Answer 1

Law of gravitation states that:
"The force on two point charges is directly proportion to the product of magnitude of the charges and inversely proportion to the square of distance between them"

Answer 2

Heya friend!!

The Universal Law of Gravitation states that :-
Every body in universe attracts every other body with a force which is directly proportional to the product of their masses and inversely proportional to the square of distance between them. The force acts along the line joining the two bodies.
It was formulated by Sir Isaac Newton.

Here's the derivation:-

Consider two objects of masses M and m that lie at a distance r from each other. Let F be the force of attraction between the two objects.  Now according to the universal law of gravitation as stated earlier , this force F is proportional to the product of masses of  the two objects.
F∝M×m              (1)
and the force is inversely proportional to the square of distance between these two objects that is 
F∝1r2             (2)Combining both equations (1) and (2) we get
F∝Mmr2             (3)
or
F=GMmr2             (4)
Here G is the constant known as Universal Gravitational constant and its SI unit is Nm^2/Kg^2
G=6.673×10−11Nm2Kg−2

hope that helps!