Power is the amount of energy transferred per second.

The units for power are either joules per second (J/s) or the special unit watt (W).

The power output of electrical things can be found using: power = current × voltage P = I × V

A good way of remembering the very important formula is VIP!

For high power devices, we often use the prefixes k or M: 1 kW = 1,000 W and 1 MW = 1,000,000 W.