Alternating current is flowing in an LR circu | vedclass

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(C) The impedance $Z$ of an $LR$ series circuit is given by $Z = \sqrt{R^2 + X_L^2}$,where $X_L = \omega L$ is the inductive reactance.For low frequen

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For high frequency,the limiting value of impedance is $R$.

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(C) The impedance $Z$ of an $LR$ series circuit is given by $Z = \sqrt{R^2 + X_L^2}$,where $X_L = \omega L$ is the inductive reactance.For low frequency,$\omega 	o 0$,so $X_L = \omega L 	o 0$. Thus,$Z = \sqrt{R^2 + 0^2} = R$.For high frequency,$\omega 	o \infty$,so $X_L = \omega L 	o \infty$. Thus,$Z \approx X_L = \omega L$.Comparing these with the given options,option $C$ states that for high frequency,the limiting value is $R$,which is incorrect based on the derivation. However,looking at the options provided,there seems to be a mismatch. Let's re-evaluate: As $\omega 	o \infty$,$Z 	o \infty$. As $\omega 	o 0$,$Z 	o R$. None of the options perfectly describe the limit correctly except for the behavior of $Z$ at low frequencies being $R$. Given the standard nature of this question,option $C$ is often intended to be the answer if the circuit were $RC$,but for $LR$,the impedance increases with frequency.

Alternating current is flowing in an $LR$ circuit with inductance $L$ and resistance $R$. The frequency of the source is $f = \omega / 2\pi$. Which of the following statements is correct?

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