Work, Energy and Power

Work

In physics, work is done when a force moves an object. Work = Force × distance. The unit of work is the joule (J).

Energy

Energy is the ability to do work. Common forms include:

• Kinetic energy: energy of a moving object.
• Potential energy: stored energy due to position or height.
• Heat, light, sound, chemical and electrical energy.

Law of Conservation of Energy

Energy cannot be created or destroyed, only changed from one form to another.

Power

Power is the rate of doing work. Power = Work / time. The unit is the watt (W).

Key Points

No movement means no work is done, even if you push hard against a wall.