For
example, the household line voltage of 220 V is an rms value with a peak
voltage of
vm = 2  V =  (1 414)(220 V) = 311 V
In fact, the I or rms current is the equivalent dc current that would
produce the same average power loss as the alternating current Equation
(7 7) can also be written as
P = V2 / R = I V    (since V = I R)
Example 7