Question

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

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

Answer 1

Answer: (B)

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