Q. A 50 V AC is applied across an R-C (series) network. The rms voltage across the resistance is 40 V, then the potential across the capacitance would be
A) 10 V
B) 20 V
C) 30 V
D) 40 V
Explanation
(c) For an R – C circuit
Applied voltage, $V = \sqrt{{V_{R}^{2} + V}_{C}^{2}}$
$\therefore\ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ 50 = \sqrt{(40)^{2} + V_{C}^{2}}$
$\Rightarrow \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ V_{C} = 30\ V$
Reviewed by Dr. Abubacker
Physics Educator & NEET/JEE Specialist
Ph.D. in Physics with 19+ years of teaching experience.