Question

In $L-C-R$ circuit, if $V$ is the effective value of the applied voltage, $V_R$ is the voltage across $RR,V_L$ is the effective voltage across $L,V_C$ is the effective voltage across $C$, then

• A. $V=V_R+V_L+V_C$
• B. $V^2=V_R^2+V_L^2+V_C^2$
• C. $V^2=V_R^2+(V_L-V_C{)}^2$
• D. $V^2=V_L^2+(V_R-V_C{)}^2$

Answer 1

Answer: (C)

$V^2=V_R^2+(V_L-V_C{)}^2$

Using phasor diagram.

$\Rightarrow V^2={\left(C_L-V_c\right)}^2+V_R^2$

$\therefore$ Option $C$ is correct.