Physics · 2015
NEET 2015 · 3 May · Code E · Q40
A certain metallic surface is illuminated with monochromatic light of wavelength, λ. The stopping potential for photo-electric current for this light…
A certain metallic surface is illuminated with monochromatic light of wavelength, $\displaystyle \lambda$. The stopping potential for photo-electric current for this light is $\displaystyle 3 \mathrm{~V}_0$. If the same surface is illuminated with light of wavelength $\displaystyle 2 \lambda$, the stopping potential is $\displaystyle \mathrm{V}_0$. The threshold wavelength for this surface for photo-electric effect is :
Official answer
(2)
$\displaystyle 4 \lambda$
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NEET (UG) 2015 Physics question, with the answer from NTA’s final answer key. Where our answers come from.