Physics · 2025
JEE Main · 24 January 2025, Shift 1 · Q41
What is the relative decrease in focal length of a lens for an increase in optical power by 0.1 D from 2.5D? ['D' stands for dioptre]
What is the relative decrease in focal length of a lens for an increase in optical power by $\displaystyle 0.1$ D from 2.5D ? ['D' stands for dioptre]
Official answer
From NTA’s final answer key for this paper.
(3)
$\displaystyle 0.04$
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JEE Main 2025 Physics question, with the answer from NTA’s final answer key. Where our answers come from.