Question

A $0.21H$ inductor and a $12\Omega$ resistance are connected in series to a $220V,50Hz$ ac source. The current in the circuit is :

• A. $\frac{220}{\sqrt{4400}}A$
• B. $\frac{22}{3\sqrt{5}}A$
• C. $\frac{220}{\sqrt{4550}}A$
• D. $\frac{22}{5\sqrt{3}}A$

Answer 1

The correct option is B $\frac{22}{3\sqrt{5}}A$

$X_L=L2\pi f=0.21\times 314\Omega$
$R=12\Omega$
$I=\frac{220}{\sqrt{X_L^2+R^2}}=3.28=\frac{22}{3\sqrt{5}}A$