CBSE 2025 · Region 7 · Set 1 · Q4 · 1 mark
An alternating current is given by $\displaystyle \mathrm{I}=\mathrm{I}_{0} \cos (100 \pi) \mathrm{t}$. The least time the current takes to decrease from its maximum value to zero will be :
Official answer
From CBSE’s own marking scheme for this paper.
(A)
$\displaystyle \left(\frac{1}{200}\right) \mathrm{s}$
Alternating CurrentRepresentation of AC Current and Voltage by Rotating Vectors — PhasorsApplymcqeasy
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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.