Photoelectric Work Function
The work function is the minimum energy that must be given to an electron to liberate it from the surface of a particular substance. In the photoelectric effect, electron excitation is achieved by absorption of a photon. If the photon's energy is greater than the substance's work function, photoelectric emission occurs and the electron is liberated from the surface. Excess photon energy results in a liberated electron with non-zero kinetic energy. The photoelectric work function is:
where is the Planck constant and is the minimum (threshold) frequency of the photon required to produce photoelectric emission.
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