CBSE 2026 · Region 3 · Set 2 · Q5 · 1 mark
A plano-convex lens, made of glass $\displaystyle (\mathrm{n}=1 \cdot 5)$ has a curved surface whose radius is $\displaystyle 40$ cm. The image formed of an object is of the same size as that of the object. The distance of the object from the lens is :(A)$\displaystyle 40$ cm(B)$\displaystyle 80$ cm(C)$\displaystyle 160$ cm(D)$\displaystyle 200$ cm
A plano-convex lens, made of glass $\displaystyle (\mathrm{n}=1 \cdot 5)$ has a curved surface whose radius is $\displaystyle 40$ cm. The image formed of an object is of the same size as that of the object. The distance of the object from the lens is :
(A)
$\displaystyle 40$ cm
(B)
$\displaystyle 80$ cm
(C)
$\displaystyle 160$ cm
(D)
$\displaystyle 200$ cm
Official answer
From CBSE’s own marking scheme for this paper.
(C)
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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.