Physics · 2025
JEE Main · 22 January 2025, Shift 2 · Q43
A light source of wavelength λ illuminates a metal surface and electrons are ejected with maximum kinetic energy of 2 eV. If the same surface is…
A light source of wavelength $\displaystyle \lambda$ illuminates a metal surface and electrons are ejected with maximum kinetic energy of $\displaystyle 2$ eV. If the same surface is illuminated by a light source of wavelength $\displaystyle \frac{\lambda}{2}$, then the maximum kinetic energy of ejected electrons will be (The work function of metal is $\displaystyle 1$ eV)
Official answer
From NTA’s final answer key for this paper.
(3)
$\displaystyle 5$ eV
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JEE Main 2025 Physics question, with the answer from NTA’s final answer key. Where our answers come from.