The average dissipated power in a resistor in a ac circuit is:
where R is the resistance, and
is the root mean square current, defined as
where
is the peak value of the current. Substituting the second formula into the first one, we find
and if we re-arrange this formula and use the data of the problem, we can find the value of the peak current I0:
where R is the resistance, and
where
and if we re-arrange this formula and use the data of the problem, we can find the value of the peak current I0: