The combination of reactive power and true power is called apparent power and it is the product of a circuits voltage and current without reference to phase angle. You can measure the input power by taking AC measurements say 1A at 120VAC 120 Watts. To raise 2 to the 8th power.
For historical reasons the horsepower is occasionally used to describe the power delivered by a machine.
This expression can be written in a shorter way using something called exponents. Thus a Watt is equivalent to a Joulesecond. In Excel exponentiation is handled with the caret operator so. The power of a test is the probability that we can the reject null hypothesis at a given mean that is away from the one specified in the null hypothesis.