Question

If a current I given by $I_o sin \bigg( \omega t -\frac{\pi}{2}\bigg)$ flows in an ac circuit across which an ac potential of $E = E_0 sin \omega t$has been applied,
then the power consumption P in the circuit will be
(a) $p = \frac{E_0 I_0}{\sqrt{2}}$
(b) $p =\sqrt{2}E_0 I_0$
(c) $p = \frac{E_0 I_0}{2}$
(d) P = 0

Answer 1

hey mate $p=\frac{E_01_0}{\sqrt{2}}$

Answer 2

As instantaneous power = Vrms Irms cosa

Vrms = Vo/√2

Irms = Io/√2

cos a = cos pie/2 = 0

so power = Vo Io cos 90., /2

= 0