Write phase difference between current and voltage for an ac circuit, when (i) f = fr, (ii) f < fr (iii) f > fr Here fr is the resonant frequency.

Write phase difference between current and voltage for an ac circuit,

1.	Write phase difference between current and voltage for an ac circuit, when (i) f = fr, (ii) f < fr (iii) f > fr Here fr is the resonant frequency.
Answer» (i) f = f_r when X_L = X_C The circuit is purely resistive i.e., it is non-inductive. Therefore, current and voltage in the circuit are in the same phase. (ii) f < f_r as X_L = ωL = 2πfL and X_C = \(\frac{1}{\omega C}=\frac{1}{2 \pi f C}\) ∴ When f is small, X_L is small, X_C is large. The circuit is capacitance dominated. Therefore, current in the circuit leads the voltage by phase angle ϕ. (iii) f > f_r So, X_L becomes large and X_C becomes small. The circuit is inductance dominated. The current lags behind the voltage by phase angle ϕ.

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Write phase difference between current and voltage for an ac circuit, when (i) f = fr, (ii) f &lt; fr (iii) f &gt; fr Here fr is the resonant frequency.

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Write phase difference between current and voltage for an ac circuit, when (i) f = fr, (ii) f < fr (iii) f > fr Here fr is the resonant frequency.