# Formula Potential energy in the gravitational field Potential energy

## Potential energy

Unit
Potential energy of a body in the gravitational field of a planet.

The formula is an approximation for the potential energy if the body is not too far away from the planet.

## Gravitational acceleration

Unit
Acceleration experienced by any body when held above a planet. On Earth, the acceleration is approximately $$g = 9.8 \, \frac{\mathrm{m}}{\mathrm{s}^2}$$. A body that is not dropped also experiences this acceleration (and thus a force $$m\,g$$), even though the body is not moving. This acceleration is compensated by a counteracting force (e.g. by holding the body with the hand).

## Height

Unit
The height from which a body is dropped above the planet. More precisely, it is a height difference between the height at which the body is and the zero point of potential energy. The zero point of energy does not necessarily have to be set on the surface of the earth. The zero point of energy can also be set on the roof of a house.

When specifying the potential energy, it is therefore also important to know with respect to which zero point the potential energy is measured. With respect to the ground, with respect to the sea level or maybe with respect to the roof of the house?

## Mass

Unit
Mass of the body of which the potential energy is to be calculated.