CBSE 2026 · Region 1 · Set 3 · Q7 · 1 mark
Light from a small object in air falls on a spherical glass surface $\displaystyle (\mathrm{n}=1.5)$ of radius of curvature R. A real image of the object will be formed if the object distance $\displaystyle \mathrm{u}$ is related to $\displaystyle \mathrm{R}$ as :
Official answer
From CBSE’s own marking scheme for this paper.
(D)
$\displaystyle \mathrm{u}>2 \mathrm{R}$
Ray Optics and Optical InstrumentsRefraction at Spherical Surfaces and by LensesApplymcqmedium
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CBSE Class 12 Physics past-paper question from the 2026board exam, with the answer as CBSE’s own marking scheme gives it. Where our answers come from.