In an a.c circuit, the instantaneous e.m.f and current are given by $e = 100 \sin 30 t$, $i=20\sin\left(30t+\frac{\pi}{4}\right)$. In one cycle of a.c the average power consumed by the circuit and the wattless current are, respectively: |
$\frac{50}{\sqrt{2}},0$ $50,0$ $50,10$ $\frac{1000}{\sqrt{2}},10$ |
$\frac{1000}{\sqrt{2}},10$ |
$\text{Average Power consumed is }P_{av} =V_{rms}I_{rms}cos\phi $ $\Rightarrow P_{av} = \frac{100}{\sqrt 2} \frac{20}{\sqrt 2} \frac{1}{\sqrt 2} = \frac{1000}{\sqrt 2}$ $\text{Wattless Current } I = I_{rms} cos \phi = 10A$ |