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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 the anode potential is increased? In each case, all other factors remain the same. Explain, giving justification in each case.
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Solution
With an increase in the accelerating potential, the photoelectric current increases first, reaches maximum when all the electrons gets collected at the positive potential plate and then remains constant. The maximum value of the anode current is called the saturation current.
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