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COMEDK2020PhysicsAlternating Current

For a series L-C-R circuit at resonance, which statement is not true?

Options

  1. AWattless current is zero.
  2. BPower factor is zero.
  3. CPeak energy stored by a capacitor = peak energy stored by an inductor.
  4. DAverage power = Apparent power.

Correct answer

B. Power factor is zero.

Step-by-step solution

In L-C R series resonance circuit, X_ L_ L =X_ C Impedance, Z= R²+ (X_ L -X_ C )² - R²+0² Z=R Power factor, cos = n Z = R R =1 Which is not zero. Since, circuit behaves like a resistive circuit. So , power loss occurs always in this circuits. i.e, wattless carrent is zero.

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