CBSE 2025 · Region 2 · Set 1 · Q16 · 1 mark
Assertion (A) : In an ideal step-down transformer, the electrical energy is not lost.
Reason (R) : In a step-down transformer, voltage decreases but the current increases.
Official answer
From CBSE’s own marking scheme for this paper.
(B)
If both Assertion (A) and Reason (R) are true but Reason (R) is not the correct explanation of Assertion (A) .
Alternating CurrentTransformersAnalyseassertion_reasonmedium
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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.