Between every particle of matter of one body and every particle of matter of another body is a gravity bond. The total strength of all the gravity bonds between two bodies is the weight of either body.

When energy goes up, bonds get weaker. When energy goes down, bonds get stronger.

The formula for kinetic energy is:

KE = ½ mv ²

When kinetic energy goes up, gravity bonds get weaker.

The rest weight of a body is how much the body weighs when it isn’t moving. The formula for rest weight is:

RW = GMm ⁄ r

G is a constant. M and m are the masses of two bodies, r is the distance between their centers.

The formula for weight is:

W = GMm ⁄ r − ½ mv ²

If a body is raised to a height, its weight goes down. Less weight means weaker gravity bonds. Weaker bonds mean more energy. The energy that goes up when a body is raised to a height is gravitational potential energy.