Electric power is the amount of work done by an electric current in a unit time. When a current flows in a circuit with resistance, it does work. Devices can be made that convert this work into: 1. * heat (electric heaters), light (light bulbs and neon lamps) 2. * motion, that is, kinetic energy (electric motors). Electric power, like mechanical power, is represented by the letter P in electrical equations, and is measured in units called watts (symbol W), after Scottish engineer James Watt.