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JEE Main20241 Feb 2024Morning ShiftPhysicsAlternating CurrentActual

In series LCR circuit, the capacitance is changed from C to 4 C . To keep the resonance frequency unchanged, the new inductance should be :

Options

  1. Areduced by 1 4 L
  2. Bincreased by 2 L
  3. Creduced by 3 4 L
  4. Dincreased to 4 L

Correct answer

C. reduced by 3 4 L

Step-by-step solution

As resonance frequency remains unchanged, therefore ω ' = ω ⇒ 1 L ' C ' = 1 L C ⇒ L ' C ' = L C ⇒ L ' 4 C = L C ⇒ L ' = L 4 ∵ Inductance must be decreased by 3 L 4 .

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