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In Photoelectric Effect, Why Should the Photoelectric Current Increase as the Intensity of Monochromatic Radiation Incident on a Photosensitive Surface is Increased? Explain.

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Question

In photoelectric effect, why should the photoelectric current increase as the intensity of monochromatic radiation incident on a photosensitive surface is increased? Explain.

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Solution

Photoelectric effect is a one photon-one electron phenomenon. Therefore, when the intensity of radiation incident on the surface increases, the number of photons per unit area per unit time increases (since intensity of incident radiation ∝ no. of photons). Hence, the photoelectrons ejected will be large, which, in turn, will contribute to the increase in photoelectric current.
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2013-2014 (March) Foreign Set 1

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