CBSE 2025 · Region 2 · Set 2 · Q9 · 1 mark
The focal length of a concave mirror in air is $\displaystyle \mathrm{f}$. When the mirror is immersed in a liquid of refractive index $\displaystyle \frac{5}{3}$, its focal length will become
Official answer
From CBSE’s own marking scheme for this paper.
(D)
f
Ray Optics and Optical InstrumentsReflection of Light by Spherical MirrorsUnderstandmcqmedium
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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.