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प्रश्न
Draw a plot showing the variation of photoelectric current with collector plate potential for two different frequencies, v1 > v2, of incident radiation having the same intensity. In which case will the stopping potential be higher? Justify your answer.
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उत्तर
Effect of frequency of the incident radiation:
Taking radiations of different frequencies but of same intensity, the variation between photoelectric current and potential of plate A is obtained and shown in graph given below:
From the graph, we note:
(i) The value of stopping potential is different for radiation of different frequency.
(ii) The value of stopping potential is more negative for radiation of higher incident frequency.
(iii) The value of saturation current depends on the intensity of incident radiation, but is independent of the frequency of the incident radiation.
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संबंधित प्रश्न
The photoelectric work function for a metal surface is 2.3 eV. If the light of wavelength 6800A is incident on the surface of metal, find threshold frequency and incident frequency. Will there be an emission of photoelectrons or not?
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(i) In which case is the stopping potential more and why?
(ii) Does the slope of the graph depend on the nature of the material used? Explain.
Two monochromatic beams, one red and the other blue, have the same intensity. In which case (i) the number of photons per unit area per second is larger, (ii) the maximum kinetic energy of the photoelectrons is more? Justify your answer.
A beam of monochromatic radiation is incident on a photosensitive surface. Answer the following question giving reason :
Does the kinetic energy of the emitted electrons depend on the intensity of incident radiation?
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With reference to the photoelectric effect, what is meant by threshold wavelength?
Plot a labelled graph of IVsl where Vs is stopping potential versus frequency f of the incident radiation.
State how will you use this graph to detennine the value of Planck's constant.
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