CBSE 2025 · Region 1 · Set 2 · Q4 · 1 mark
A circular coil of diameter $\displaystyle 15$ mm having $\displaystyle 300$ turns is placed in a magnetic field of $\displaystyle 30$ mT such that the plane of the coil is perpendicular to the direction of magnetic field. The magnetic field is reduced uniformly to zero in $\displaystyle 20$ ms and again increased uniformly to $\displaystyle 30$ mT in $\displaystyle 40$ ms. If the emfs induced in the two time intervals are $\displaystyle \mathrm{e}_{1}$ and $\displaystyle \mathrm{e}_{2}$ respectively, then the value of $\displaystyle \mathrm{e}_{1} / \mathrm{e}_{2}$ is
Official answer
From CBSE’s own marking scheme for this paper.
(C)
$\displaystyle 2$
Electromagnetic InductionFaraday’s Law of InductionApplymcqmedium
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CBSE Class 12 Physics past-paper question from the 2025board exam, with the answer as CBSE’s own marking scheme gives it. Where our answers come from.