Question

A circuit excited by voltage V has a resistance R which is in series with an inductor and a capacitor connected in parallel. The voltage across the resistor at the resonant frequency is ___________

(a) 0

(b) \(\frac{V}{2}\)

(c) \(\frac{V}{3}\)

(d) V

Answer 1

The correct answer is (a) 0

The best I can explain: Dynamic resistance of the tank circuit, ZDY = \(\frac{L}{R_LC}\)

But given that RL = 0

So, ZDY = \(\frac{L}{0XC}\) = ∞

Therefore current through the circuit, I = \(\frac{V}{∞}\) = 0

∴ VD = 0.