CBSE 2025 · Region 7 · Set 1 · Q14 · 1 mark
Assertion (A) : A ray of light is incident normally on the face of a prism. The emergent ray will graze along the opposite face of the prism when the critical angle at glass-air interface is equal to the angle of the prism. Reason ( $\displaystyle R$ ) : The refractive index of a prism depends on angle of the prism.
Official answer
From CBSE’s own marking scheme for this paper.
(C)
Assertion (A) is true, but Reason (R) is false.
Ray Optics and Optical InstrumentsRefraction through a PrismUnderstandassertion_reasonhard
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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.