A series LCR circuit with L = 5.0 H, C = 80 μF and R = 40 Ω is connected to a variable frequency 200 V source. The amplitude of current at the resonant frequency is

5.0 A

The correct answer is Option (3) → 7.1 A

At resonance, impedance $Z = R$

Given: $R = 40 \ \Omega$, $V = 200 \ \text{V}$

Current amplitude: $I = \frac{V}{R}$

$I = \frac{200}{40} = 5 \ \text{A}$

∴ Amplitude of current at resonance $= 5 \ \text{A}$