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99 Percentile Qs Bank for JEE MainPhysicsAlternating Current

The natural frequency of an L-C circuit is 125 kHz . When the capacitor is totally filled with a dielectric material, the natural frequency decreases by 25 kHz . Dielectric constant of the material is nearly

Options

  1. A3.33
  2. B2.12
  3. C1.56
  4. D1.91

Correct answer

C. 1.56

Step-by-step solution

The natural frequency, f_ N = 1 2 K L C = Fe When capacitor is totally filled with dielectric material of dielectric constant K then capacitance C ^ C = KC aligned & f_ C ^ = 1 2 K L C & f_C f_ C^ = 1 / 2 L C 1 / 2 K L C = K & 125 10^3 100 10^3 = K S 4 = K & [ f _ c =125 kHz -25 kHz =100 kHz =100 10^3 ~Hz ] & K= ( 5 4 )^2= 25 16 =1.562 aligned

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