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Most Important Selected Qs for JEE AdvancedPhysicsAlternating Current

A given LCR series circuit satisfies the condition for resonance with a given A C source. If the angular frequency of the AC source is increased by 100 % , then in order to establish resonance, and without changing the value of inductance, capacitance must be

Options

  1. AIncreased by 100 %
  2. BReduced by 50 %
  3. CIncreased by 75 %
  4. DReduced by 75 %

Correct answer

C. Increased by 75 %

Step-by-step solution

At resonance, L = 1 C , in second case for resonance, 2 ~L = 1 2 c ^ C^ = 1 4 ^2 L = L C 4 L = C 4 C C = 3 4

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