K.Eλ=λhc−ϕ
K.E2λ=2λhc−ϕ
K.E2λ=3(K.Eλ)
⇒ϕ=2λhc
JEE Main 2016 — Physics Modern Physics
A photoelectric surface is illuminated successively by monochromatic light of wavelengths λand2λ. If the maximum kinetic energy of the emitted photoelectrons in the second case is 3 times that in the first case, the work function of the surface is :
Held on 10 Apr 2016 · Verified 6 Jul 2026.
2λhc
λhc
3λhc
λ3hc
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