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# Power

From Appropedia

*For electrical power and other forms of power, see***Energy**.

# Definition[edit]

In a physics term, **power** is the rate at which work takes place or energy is transmitted. It can also be defined as the amount of energy needed or used to complete an activity over a period of time.

# Units[edit]

The SI unit for power is the the Watt or "W". Other non SI units include:

- horsepower "HP",
- calories per hour, "cal/hr", and
- foot pounds per minute "ft-lb/min".

## Equation[edit]

The equation for power is where P is power, W is work and t is time. A second equation for power is where E is energy and t is time.