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Q.
At resonance frequency the impedance in series $LCR$ circuit is
Alternating Current
Solution:
At resonance frequency, the inductive and capacitive reactance are equal.
i.e. $X_L = X_c$
$\therefore $ Impedance, $Z=\sqrt{R^{2}+\left(X_{L}-X_{C}\right)^{2}}$
$=\sqrt{R^{2}+0^2}$
$=R$