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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
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(b) the total energy of the photons emitted per unit time increases
(c) more energetic photons are emitted
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(d) electric charge of the photoelectrons is quantised
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What changes the polarity between the plates?
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