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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.
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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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