Power

Definition: Power is the time rate of doing work or, the amount of work done per second.

Average Power:

$$\bar{P} {\frac{W}{\Delta t}} {\frac{\Delta s}{\Delta t}} \bar{v}$$ (9)

where $\Delta$t is the time interval in which the work is done.

Instantaneous Power:

Note:

• Power is a scalar.
• SI Units: 1 Watt (  W ) = 1  Joule/sec = 1  kg m ²/  s ³
• British Engineering Units: 1 horsepower (  hp ) = 746  W .