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Question
How would the stopping potential for a given photosensitive surface change if the frequency of the incident radiation were increased? Justify your answer.
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Solution
The stopping potential for a certain photosensitive surface increases as the frequency of the incident radiation increases. This is because the stopping potential is directly proportional to the frequency of the incident radiation, according to the photoelectric effect equation: Kmax = hf - Φ, where h is Planck's constant, f is the frequency of incident radiation and the metal's work function. Kmax is the photoelectron's maximal kinetic energy. As a result, as the frequency of the input radiation increases, so does the stopping potential required to stop the photoelectrons, while the kinetic energy of the photoelectrons emitted decreases.
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