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JEE Main202131 Aug 2021Morning ShiftPhysicsAlternating CurrentActual

In an ac circuit, an inductor, a capacitor and a resistor are connected in series with X L = R = X C . Impedance of this circuit is :

Options

  1. AZero
  2. BR
  3. CR 2
  4. D2 R 2

Correct answer

B. R

Step-by-step solution

Recall the formula of impedance is in terms of resistance, Z = X L - X C 2 + R 2 , here, the condition of resonance, X L = X C , it means, Z = X L - X L 2 + R 2 = R

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