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Question
Plot a graph showing the variation of photoelectric current, as a function of anode potential for two light beams having the same frequency but different intensities I1 and I2 (I1 > I2). Mention its important features.
Solution
We use radiations with varying frequencies but the same intensity. When the frequency increases, the photoelectric current increases, and when the frequency decreases, the photoelectric current decreases. However, beyond a particular anode potential, the photoelectric current remains constant for all radiations of different frequencies. This is referred to as saturation current. As a result, the saturation current is unaffected by radiation frequency.
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