Description: When light or other electromagnetic radiation strikes a material, electrons can, depending on the material and frequency of the light, be emitted: This is the photoelectric effect. It can be explained by considering light as particles or packets of energy called photons. For materials, mostly metals, the frequency of light should be greater than a threshold frequency (characteristic of the material) for the emission of these photoelectrons to occur. Their maximum energy is determined by the frequency; increasing the frequency of the light brings about an increase in the maximum kinetic energy of the electrons. On increasing the intensity of monochromatic light, more electrons are released, but there is no change in their maximum kinetic energy. This is because the intensity of the light is directly proportional to the number of photons.

Related Terms:

• Electron

Term and definition status: This term and its definition have been approved by a research astronomer and a teacher

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