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Question
Light of wavelength λ falls on a metal with work-function hc/λ0. Photoelectric effect will take place only if
Options
λ ≥ λ0
λ ≥ 2λ0
λ ≤ λ0
λ < λ0/2
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Solution
λ ≤ λ0
As the work-function of the metal is hc/λ0, its threshold wavelength is λ0.
For photoelectric effect, the wavelength of the incident light should be less than or equal to the threshold wavelength of the metal on which light is incident.
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