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JEE Main202127 Jul 2021Evening ShiftPhysicsAlternating CurrentActual

A 100 Ω resistance, a 0 . 1 μ F capacitor and an inductor are connected in series across a 250 V supply at variable frequency. Calculate the value of inductance of inductor at which resonance will occur. Given that the resonant frequency is 60 Hz .

Options

  1. A0 . 70 H
  2. B70 . 3 mH
  3. C7 . 03 × 10 - 5 H
  4. D70 . 3   H

Correct answer

D. 70 . 3   H

Step-by-step solution

C = 0 . 1 μ F = 10 - 7   F Resonant frequency = 60   Hz ω o = 1 LC 2 π f 0 = 1 L C ⇒ L = 1 4 π 2 f 0 2 C by putting values L ≃ 70 . 3   Hz .

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