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प्रश्न
Light of wavelength λ falls on a metal with work-function hc/λ0. Photoelectric effect will take place only if
विकल्प
λ ≥ λ0
λ ≥ 2λ0
λ ≤ λ0
λ < λ0/2
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उत्तर
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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संबंधित प्रश्न
A mercury lamp is a convenient source for studying frequency dependence of photoelectric emission, since it gives a number of spectral lines ranging from the UV to the red end of the visible spectrum. In our experiment with rubidium photo-cell, the following lines from a mercury source were used:
λ1 = 3650 Å, λ2 = 4047 Å, λ3 = 4358 Å, λ4 = 5461 Å, λ5 = 6907 Å,
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