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प्रश्न
An increase in the intensity of the radiation causing photo-electric emission from a surface does not affect the maximum K.E. of the photoelectrons. Explain.
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उत्तर
The current in the photoelectric cell increases as the intensity of the incident light increases. However, the energy of the photons (hν) does not rise with increasing intensity, and hence the kinetic energy of the released electrons does not increase.
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संबंधित प्रश्न
The threshold frequency for a certain metal is 3.3 × 1014 Hz. If light of frequency 8.2 × 1014 Hz is incident on the metal, predict the cut-off voltage for the photoelectric emission.
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| Metal | Work Function (eV) |
| Na | 1.92 |
| K | 2.15 |
| Ca | 3.20 |
| Mo | 4.17 |
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In various experiments on photo electricity, the stopping potential for a given frequency of the incident radiation is ______.
