Consider a circuit with Resistance, Inductor and Capacitor connected in series. The phase difference between the current and the alternating voltage (at resonance) is:

Correct option is A

​$$\text{In Series LCR Circuit:} \\\text{At resonance, the inductive reactance } X_L \text{ and the capacitive reactance } X_C \text{ become equal.} \\\text{Thus, at resonance:} \\V = I R \\\text{Phase Angle:} \\\text{The phase angle } \phi \text{ in a series LCR circuit is given by:} \\\tan \phi = \frac{X_L - X_C}{R} \\\text{At resonance, since } X_L = X_C: \\\tan \phi = 0 \quad \Rightarrow \quad \phi = 0^\circ$$​​

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