If a current flowing in a coil is reduced to half of its initial value, the relation between the new energy (E₂) and the original energy (E₁) stored in the coil will be (a) E₂ = E₁/4 (b) E₂ = E₁/2 (c) E₂ = E₁ (d) E₂ = 4E₁

Answer: (a). Energy stored in a coil: E = 1/2LI², so E ∝ I². I₂ = I₁/2 ⇒ E₂ = E₁/4 So the answer is (a).

If a current flowing in a coil is reduced to half of its initial… | MHT CET 2021 (22 Sep, Shift 1)

Q36MHT CET 2021 · 22 SEP · SHIFT 1Medium

Electrical Power & Heating Effect

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 $(E_1)$ stored in the coil will be

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Answer: (a)

Energy stored in a coil: $E = \frac{1}{2}LI^2$ , so $E \propto I^2$ .
$I_2 = \frac{I_1}{2} \Rightarrow E_2 = \frac{E_1}{4}$
So the answer is (a).

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