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MHT CET202122 Sep 2021Morning ShiftPhysicsElectromagnetic InductionActual

If a current flowing in a coil is reduced to half of its initial value, the relation between the new energy ( E ₂ ) and the original energy (E₁ ) stored in the coil will be

Options

  1. AE₂= E₁ 4
  2. BE₂= E₁ 2
  3. CE ₂= E ₁
  4. DE ₂= 4E ₁

Correct answer

A. E₂= E₁ 4

Step-by-step solution

aligned & E₁= 1 2 L₁^2, E₂= 1 2 L₂^2 & E₂ E₁ = ( I₂ I₁ )^2= ( 1 2 )^2= 1 4 & E₂= E₁ 4 aligned

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