Question

In a series LCR circuit the frequency of a 10V, AC voltage source is adjusted in such a fashion that the reactanace of the inductor measures 15 $\Omega$ and that of the capacitor 11$\Omega$,. If R = 3 $\Omega$ the potential difference across the series combination of L and C will be:

• A. 8 V
• B. 10 V
• C. 22 V
• D. 52 V

Answer 1

The correct option is A 8 V

$I=\frac{V}{Z}=\frac{V}{\sqrt{R^2+[X_L-X_C{]}^2}}=\frac{10}{\sqrt{3^2+[15-11{]}^2}}$
$=\frac{10}{5}=2A$
$V_L-V_C=I[X_L-X_C]=2[15-11]$
= 8V