Question

At resonance frequency the impedance in series $LCR$ circuit is

• A. maximum
• B. minimum
• C. zero
• D. infinity

Answer 1

Answer: (B)

minimum

Answer 2

At resonance frequency, the inductive and capacitive reactance are equal. i.e. $X_L = X_c$ $\therefore$ Impedance, $Z=\sqrt{R^{2}+\left(X_{L}-X_{C}\right)^{2}}$ $=\sqrt{R^{2}+0^2}$ $=R$