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99 Percentile Qs Bank for JEE MainPhysicsAlternating Current

The natural frequency of an L-C circuit is 1,25,000 cycle / s . Then the capacitor C is replaced by another capacitor with a dielectric medium of dielectric constant K . In this case, the frequency decreases by 25 kHz . The value of K is

Options

  1. A3.0
  2. B2.1
  3. C1.56
  4. D1.7

Correct answer

C. 1.56

Step-by-step solution

f= 1 2 L C or f 1 C When capacitor C is replaced by another capacitor C^ of dielectric constant K , then gathered C^ =K C f^ f = C C^ 125000-25000 125000 = C K C 100 125 = 1 K K= ( 125 100 )^2=1.56 gathered

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