Power
In physics, power is the rate at which physical work of some kind is done, or the amount of energy that is transferred per unit of time. It involves a physical system changing over a specified time.
The equation for power is often written as:
Power = work/time
According to the International System of Units (SI), the unit of power is the joule per second (J/s), which is also known as a ‘watt’ (named after James Watt, the inventor of the steam engine condenser). Another measurement is horsepower, in which power is compared to the power of a notional horse.
Mechanical power is typically described as the time derivative of work, and is the combination of forces and movement.
Power can also relate to electricity; specifically, electrical power is the rate per unit time at which an electric circuit transfers electrical energy. The term 'power generation' describes the process of generating electrical power, and electric generators, or sources such as electric batteries, are commonly used to provide electrical power.
See also: Electrical power.
[edit] Related articles on Designing Buildings
- Alternating current and direct current
- Ampere.
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- Combined heat and power.
- Electrical power.
- Electricity supply.
- Energy.
- Energy consumption.
- Energy storage.
- Hydroelectricity.
- Horsepower.
- Kilowatt hour.
- Micro-grids.
- Microgeneration.
- On-site generation of heat and power.
- Power factor for lamps.
- Power generation.
- Power over ethernet.
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- Renewable energy.
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- Uninterrupted power supply for buildings.
- Voltage.
- Watt.
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