Electric power
Electric power is defined as the power dissipated by an electric circuit. Electric power is a measurement of the rate at which energy is used over a period of time. The SI unit for power is the watt, the unit for energy is the joule, and the unit for time is the second.
For a direct current circuit, electric power equals the electric current multiplied by the voltage.
When electric current flows through a circuit, it is slowed down by the resistance in the circuit. Devices can convert this current to useful forms of work, such as heat radiation, light emission, mechanical motion, or acoustic vibrations.
Electric Power Media
Electric power is transmitted by overhead lines like these, and also through underground high-voltage cables.
Animation showing power source
Animation showing electric load
Transmission of power through an electric circuit
Power triangle: The components of AC power
Related pages
References
- Reports on August 2003 Blackout, North American Electric Reliability Council website Archived 2006-06-16 at the Wayback Machine
- Croft, Terrell; Summers, Wilford I. (1987). American Electricians' Handbook (Eleventh ed.). New York: McGraw Hill. ISBN 0-07-013932-6. Archived from the original on 2006-06-17. Retrieved 2007-04-09.
- Fink, Donald G.; Beaty, H. Wayne (1978). Standard Handbook for Electrical Engineers (Eleventh ed.). New York: McGraw Hill. ISBN 0-07-020974-X. Archived from the original on 2006-10-16. Retrieved 2007-04-09.
