Physics · 2025
JEE Main · 23 January 2025, Shift 2 · Q43
In photoelectric effect an em-wave is incident on a metal surface and electrons are ejected from the surface. If the work function of the metal is…
In photoelectric effect an em-wave is incident on a metal surface and electrons are ejected from the surface. If the work function of the metal is $\displaystyle 2.14$ eV and stopping potential is 2V, what is the wavelength of the em-wave ?
(Given $\displaystyle \mathrm{hc}=1242 \mathrm{eVnm}$ where h is the Planck's constant and c is the speed of light in vaccum.)
Official answer
From NTA’s final answer key for this paper.
(1)
$\displaystyle 300$ nm
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JEE Main 2025 Physics question, with the answer from NTA’s final answer key. Where our answers come from.