Newton’s Law of Gravity
However, because the strength of gravity is very weak, the force of attraction is very weak. For one kilogram separated from another kilogram by one meter:
(6.67 x 10-11 Nt-m2/kg2)*(1 kg)*(1 kg) / [1 m]2
= 6.67 x 10-11 Nt (a very small force).