CBSE 2025 · Region 1 · Set 2 · Q8 · 1 mark
The speed of light in two media' $\displaystyle 1$ 'and' $\displaystyle 2$ 'are $\displaystyle v_{1}$ and $\displaystyle v_{2}\left(>v_{1}\right)$ respectively. For a ray of light to undergo total internal reflection at the interface of these two media, it must be incident from
Official answer
From CBSE’s own marking scheme for this paper.
(A)
medium' $\displaystyle 1$ 'and at an angle greater than $\displaystyle \sin ^{-1}\left(\frac{v_{1}}{v_{2}}\right)$
Ray Optics and Optical InstrumentsTotal Internal ReflectionRemembermcqmedium
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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.