When a force (F) moves and object through a distance (d) then work is done and energy is transferred.

Work done (W) is measured in joules (J). Energy transferred is measured in joules (J).

Work done = Energy Transferred

Work done = force x distance moved

(joules, J) (newtons, N) (metres, m)

**Power**

Power (P) is the work done in a given time, it is measured in watts (W). One watt is one joule per second.

Power = energy transferred

time

**Gravitational Potential Energy**

This is the energy an object gains when it is lifted up in a gravitational field, it is measured in joules (J).

change in GPE = mass x gravitational field strength x change in height

(joules, J) (kilogram, kg) (newtons per kilogram, N/kg) (metres, m)

**Kinetic energy**

The kinetic energy of an object depends on its mass and speed, it is measured in joules (J).