Which one of the following graph represent correctly the variation of impedance (Z) of a series LCR circuit with the frequency ( v ) of applied a.c.?

Step-by-step solution

Z= R^2+ (2 v L- 1 2 C )^2 From above equation at v=0 Z= When v= 1 2 LC (resonant frequency). Z = R For v 1 2 L C Z starts increasing. i.e., for frequency 0-v_r, Z decreases and for v_r to , Z increases. This is justified by graph (B).