POWER
Power is the rate of change of work with respect to time. This is a useful concept to evaluate the performance of a system, such as calculating energy losses when comparing input power to output power. Using the principle of work and energy, power can be calculated as:
(1) (dW)/(dt) = ΣFi⋅Vi + ΣCi⋅ωi
where Fi are external forces, Vi is the velocity of the mass center, ωi is the angular velocity about the mass center, and Ci are external moments. Power can be integrated to get the value of work, and power can be used to give an indication of how much work can be done over a time period.