# Question #551ee

Dec 24, 2016

When you do work on an object, you do work against a force and transfer energy in the process. This can result in an increase in potential energy

#### Explanation:

When you do work on an object, you do work against a force and transfer energy in the process. The work done is defined as:

$W D = F \times S$

where F is the force and S is the distance moved in the direction of the force.

If you lift a mass through a height, $h$, you do work against gravity. The force required is equivalent to the weight of the object. Hence the work done is:

$W D = m g h$

It can be seen that this is identical to the equation for gravitational potential energy:

$P E = m g h$

In other words, by lifting the mass, work is done on the object resulting in a corresponding increase in its potential energy.

This effect is not confined to gravitational fields. For example, moving a charge in an electric field would require work to be done and a corresponding change in potential energy.