Using photoelectric equation, hf−hf0=21mv2=eVs
Or (λhc−λ0hc)=eVs
For the first case, λhc−λ0hc=e(3V0) ...(i)
For the second case, 2λhc−λ0hc=e(V0) ...(ii)
Solving λ0=4λ
When a certain metallic surface is illuminated with monochromatic light of wavelength λ, the stopping potential for photoelectric current is 3V0 and when the same surface is illuminated with light of wavelength 2λ, the stopping potential is V0. The threshold wavelength of this surface for photoelectric effect is
Held on 30 Apr 2015 · Verified 9 Jul 2026.
6λ
4λ
4λ
6λ
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