In mathematical terms, it is expressed as:
$$P = \dfrac{E}{t}$$ where $P$ is the power,The standard unit of power is the watt (W), where one watt equals one joule of work done per second (1 W = 1 J/s). For example, if a person does 100 joules of work in 20 seconds, the power exerted is 5.0 watts.