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प्रश्न
List out the laws of photoelectric effect.
उत्तर
Laws of photoelectric effect:
- For a given frequency of incident light, the number of photoelectrons emitted is directly proportional to the intensity of the incident light. The saturation current is also directly proportional to the intensity of incident light.
- Maximum kinetic energy of the photoelectrons is independent of the intensity of the incident light.
- Maximum kinetic energy of the photoelectrons from a given metal is directly proportional to the frequency of incident light.
- For a given surface, the emission of photoelectrons takes place only if the frequency of incident light is greater than a certain minimum frequency called the threshold frequency.
- There is no time lag between the incidence of light and the ejection of photoelectrons.
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संबंधित प्रश्न
When a metallic surface is illuminated with radiation of wavelength λ, the stopping potential is V. If the same surface is illuminated with radiation of wavelength 2λ, the stopping potential is `"V"/4`. The threshold wavelength for the metallic surface is
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How will you define threshold frequency?
Mention the different types of photocells.
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List out the characteristics of photons.
Give the applications photocell.
Calculate the maximum kinetic energy and maximum velocity of the photoelectrons emitted when the stopping potential is 81 V for the photoelectric emission experiment.
Calculate the energies of the photons associated with the following radiation:
- violet light of 413 nm
- X-rays of 0.1 nm
- radio waves of 10 m
