The Cavendish Experiment helped establish the following equation: G=Fd2/mm1. G is the force of gravity. The two ms (m and m1) are the masses of the bodies involved. The d is the distance between the centers of the bodies.

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Cavendish separated two lead balls (each two inches in diameter) by a very thin wire approximately a meter in length. He then suspended the wire from the ceiling at a point halfway between the two balls. Cavendish then placed a lead ball eight inches in diameter near each one of the two-inch balls on opposite sides. As he did this, the thin wire twisted as the force of gravity between the lead balls pulled them toward each other. His experiment allowed him to estimate the Newton Gravitational Constant.