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Question
List out the laws of photoelectric effect.
Solution
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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