CBSE 2026 · Region 1 · Set 1 · Q9 · 1 mark
A concave lens of focal length $\displaystyle 10$ cm is cut into two identical plano-concave lenses. The focal length of each lens will be
Official answer
From CBSE’s own marking scheme for this paper.
(A)
$\displaystyle 20$ cm
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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.