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JEE Main2011PhysicsAlternating CurrentActual

A fully charged capacitor C with initial charge q₀ is connected to a coil of self inductance L at t=0 . The time at which the energy is stored equally between the electric and the magnetic field is :

Options

  1. A4 L C
  2. B2 L C
  3. CL C
  4. DL C

Correct answer

A. 4 L C

Step-by-step solution

Charge oscillates simple harmonic motion q=q₀ t, U= 1 2 q^2 C aligned & q= q₀ 2 t= 4 & t= T 8 = 2 8 L C = 4 L C aligned

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