Power

Power is defined as the rate of change(derivative) of work with respect to time, which can be(in certain cases where we find the derivative of the total work) the derivative of kinetic energy with respect to time(which by the law of conservation of energy can be considered the derivative of potential energy with respect to time). It is mathematically defined below:

If the force is constant with respect to time:

The SI unit for power is Watts, or Joules/second.

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Keep in mind that the following definitions for power when force is constant can also be used to calculate the average power if the force isn't constant.