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Assertion : At resonance, $L C R$ series circuit have a minimum current.
Reason : At resonance, in LCR series circuit, the current and e.m.f are not in phase with each other.
Options:
Reason : At resonance, in LCR series circuit, the current and e.m.f are not in phase with each other.
Solution:
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Verified Answer
The correct answer is:
If both assertion and reason are false.
At resonance $X_L=X_C$ or $\omega L=\frac{1}{\omega C}$.
Because of this impedance of $L C R$ series
circuit become equal to resistance of circuit
$\left(Z=\sqrt{R^2+\left(X_L-X_C\right)^2}\right)$.
Therefore from $I=\frac{E}{Z}=\frac{E}{R}$, at resonance, current in LCR series circuit is maximum. Correspondingly phase angle is also equal to zero. Therefore emf and current are in phase in $L C R$ series circuit.
Because of this impedance of $L C R$ series
circuit become equal to resistance of circuit
$\left(Z=\sqrt{R^2+\left(X_L-X_C\right)^2}\right)$.
Therefore from $I=\frac{E}{Z}=\frac{E}{R}$, at resonance, current in LCR series circuit is maximum. Correspondingly phase angle is also equal to zero. Therefore emf and current are in phase in $L C R$ series circuit.
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