Power is defined as the rate at which work is done or energy is converted and transferred. It is measured in watts, which is equal to one joule per second. The formula for average power over a period of time is the amount of work done divided by the duration of the period.

1. POWER<br />In physics, power (symbol: P) is the rate at which work is performed or energy is converted and transferred. In the SI system of measurement, power is measured in watts (symbol: W). one watt is defined as the rate of work done or energy conversion of one joule per second. if ∆W is the amount of work performed during a period of time of duration ∆t, the average power Pavg over that period is given by the formula: <br />The dimension of power is energy divided by time. Which is equal to one joule per second. In mechanics, the work done on an object is related to the forces acting on it by: <br />W = F. ∆d.