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Most Important Selected Qs for JEE AdvancedPhysicsAlternating Current

Paragraph: A voltage source V = V ₀ (100 t ) is connected to a black box in which there can be either one element out of L,C,R or any two of them connected in series. At steady state the variation of current in the circuit and the source voltage are plotted together with time, using an oscilloscope, as shown. Question: If AC source is removed, the circuit is shorted and then at t=0 , a battery of constant EMF is conn

Options

  1. AIncreases exponentially with constant =0.02 sec .
  2. BDecrease exponentially with time constant =0.01 sec .
  3. COscillate with angular frequency 20 sec ⁻¹
  4. DFirst increase and then decrease.

Correct answer

B. Decrease exponentially with time constant =0.01 sec .

Step-by-step solution

For DC circuit i = i ₀ e^ - t R C and RC =0.01 sec .

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