Power = (voltage) x (current)
500 W = (120 v) x (current)
Current = (500 w) / (120 v) = 4-1/6 amperes .
Power and current are both rates.
Power is the rate of using energy ... joules per second.
Current is the rate of flowing charge ... coulombs per second.
Neither quantity depends on how long you keep it up.
They're both going on continuously while the vacuum is running.
