Question

In an $LCR$ circuit the potential difference between the terminals of the inductance is $60V$, between the terminals of the capacitor is $30V$ and that between the terminals of resistance is $40V$. The supply voltage will be equal to ______.

• A. $10V$
• B. $130V$
• C. $50V$
• D. $70V$

Answer 1

The correct option is C $50V$

Calculation of Supply voltage:
Supply voltage
$V=\sqrt{(V_R^2+(V_L-V_C{)}^2}$
Given $V_R=40V,V_L=60V,V_C=30V$
$V=\sqrt{(40{)}^2+(60-30{)}^2}$
$=\sqrt{(40{)}^2+(30{)}^2}$
$V=50V$
Thus, option $\left(A\right)$ is correct.