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Most Important Selected Qs for JEE AdvancedPhysicsElectromagnetic Induction

The circuit shown in figure consisting of three identical lamps and two coils is connected to a direct current source. The ohmic resistance of the inducting coils is negligible. The switch is closed for a long time and then opened. Which of the following statements is/are correct for the instant immediately after opening the switch?

Options

  1. AAll the lamps are turned off
  2. BBrightness of B₂ & B₃ remains unchanged
  3. CBrightness of B ₁ suddenly decreases.
  4. DBrightness of B₁ suddenly increases

Correct answer

D. Brightness of B₁ suddenly increases

Step-by-step solution

Due to self induced emf current through B ₂ and B ₃ remains unchanged but current through B ₁ increased.

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