normal dispersion

physics

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July 1, 2026

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Normal dispersion occurs in wave motion when individual waves propagate at velocities that depend on their wavelengths. In the context of light, this means that different colors (wavelengths) of light travel at different speeds through a medium, such as a glass prism. This phenomenon causes a beam of white light to spread out into its constituent colors, a process also seen in rainbows. This is in contrast to anomalous dispersion, where the normal order of component separation is reversed near certain wavelengths. The refractive index of a medium, which measures how much light bends, varies with wavelength, leading to this separation.123

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radiation
Dispersion
…with frequency, a phenomenon termed normal dispersion. The degree of refraction depends on the refractive index. The increased bending of violet light over red by a glass prism is therefore the result of normal dispersion. If experiments are done, however, with light having a frequency close to the natural electron…
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…with frequency, a phenomenon termed normal dispersion. The degree of refraction depends on the refractive index. The increased bending of violet light over red by a glass prism is therefore the result of normal dispersion. If experiments are done, however, with light having a frequency close to the natural electron…
Read More