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Physics · 2026 · 1 mark
Ray Optics and Optical InstrumentsRefraction at Spherical Surfaces and by Lenses1 markAnalyseassertion reason
CBSE 2026 · Region 4 · Set 1 · Q15
Assertion (A): When a convex lens made of glass is immersed in water, its converging power increases. Reason (R): The focal length of a lens depends…
Assertion (A) : When a convex lens made of glass is immersed in water, its converging power increases.
Reason (R) : The focal length of a lens depends only on the radii of curvature of its two faces.
Official answer
(D)
Both Assertion (A) and Reason (R) are false.
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CBSE Class 12 Physics past-paper question from the 2026 board exam, with the answer as CBSE’s own marking scheme gives it. Where our answers come from.