Power has as its main function to measure the speed with which energy is consumed or applied. Basically, the energy expended or the labor dispensed to be able to raise an object, for example, will always be the same, however, the power diagnoses the speed with which this energy is applicable to be able to raise effectively the object, that is, the power It is nothing more than the total energy or labor effected, divided by the total time necessary to accomplish it.
The unit used for mechanical power is Watt (W), however, the most usual unit for mechanical power is c.v., short for horsepower, equivalent to 736W.
Although the energy is one, it has the possibility of being achieved in different ways. If a resistor is connected to a mains with voltage, an electric current will be able to warm the resistance.
From this, resistance becomes capable of absorbing energy and consequently of transforming it into heat, which is also considered a form of energy. An electric motor can absorb electrical power from the grid and transform it into available mechanical energy at the tip of the shaft.