Question

If a circuit made up of a resistance $1\Omega$ and inductance 0.01H, and alternating emf 200 V at 50 H is connected, then the phase difference between the current and the emf in the circuit is :

Answer 1

$R=1\Omega$

$X_L=\omega L=\left(2\pi f\right)L=\pi \Omega$

Phase difference -

$\cos \varphi =\frac{R}{Z}=\frac{R}{\sqrt{R^2+X_L^2}}$ and the current lags the emf as this is an inductive circuit

$⟹\cos \varphi =\frac{R}{Z}=\frac{1}{\sqrt{1+{\pi }^2}}=0.303$

$⟹\varphi ={72.34}^o$