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प्रश्न
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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उत्तर
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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| The figure shows the variation of photoelectric current measured in a photocell circuit as a function of the potential difference between the plates of the photocell when light beams A, B, C and D of different wavelengths are incident on the photocell. Examine the given figure and answer the following questions: |

- Which light beam has the highest frequency and why?
- Which light beam has the longest wavelength and why?
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