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Question
Light of intensity ‘I’ and frequency ‘v’ is incident on a photosensitive surface and causes photoelectric emission. What will be the effect on anode current when (i) the intensity of light is gradually increased. In each case, all other factors remain the same. Explain, giving justification in each case.
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Solution
Keeping the anode potential and the frequency of the incident radiation constant, if the intensity of the incident light is increased, the photoelectric current or the anode current increases linearly. This is because photoelectric current is directly proportional to the number of photoelectrons emitted per second which is directly proportional to the intensity of the incident radiation.
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