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प्रश्न
Define the term ‘stopping potential’ in relation to photo-electric effect.
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उत्तर
If we increase the negative potential of the collector, the photoelectric current decreases rapidly. At a certain critical value of the negative potential of the collector, the photoelectric current becomes zero. This potential is called stopping potential or cut-off potential and it depends on the frequency of the incident radiation, but independent of its intensity.
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