the principle that two particles attract each other with forces directly proportional to the product of their masses divided by the square of the distance between them

The principle that expresses the force of gravitational attraction between two bodies as a function of their mass and their distance. Expressed mathematically, F = Gm1m2d2where F is the force in Newtons, m1 and m2 are the masses of the bodies in kilograms, G is the gravitational constant, and d is the distance between the bodies in meters. Newton's Principle of Gravitation is an example of an inverse square law. Also called law of gravitationlaw of universal gravitation See Note at gravity.