Answer the following question. Define the term "Threshold frequency", in the context of photoelectric emission. - Physics

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Short Note

Answer the following question.
Define the term "Threshold frequency", in the context of photoelectric emission.

Define the term ‘threshold frequency’ for a photosensitive material.

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Solution

For a given Photosensitive material, there is a certain minimum cut off frequency at which Photoelectric emission is possible is called Threshold frequency, i.e. At this frequency just emission of photoelectrons happens without giving them any kind of additional energy. Higher the work function of the material, greater is the Threshold frequency.

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