Physics · 2025
JEE Main · 8 April 2025, Shift 2 · Q41
A concave-convex lens of refractive index 1.5 and the radii of curvature of its surfaces are 30 cm and 20 cm, respectively. The concave surface is…
A concave-convex lens of refractive index $\displaystyle 1.5$ and the radii of curvature of its surfaces are $\displaystyle 30$ cm and $\displaystyle 20$ cm , respectively. The concave surface is upwards and is filled with a liquid of refractive index 1.3. The focal length of the liquid-glass combination will be
Official answer
From NTA’s final answer key for this paper.
(1)
$\displaystyle \frac{600}{11} \mathrm{~cm}$
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JEE Main 2025 Physics question, with the answer from NTA’s final answer key. Where our answers come from.