An Etymological Dictionary of Astronomy and Astrophysics
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فرهنگ ریشه شناختی اخترشناسی-اخترفیزیک

M. Heydari-Malayeri    -    Paris Observatory

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Number of Results: 1 Search : Cauchy''s equation
Cauchy's equation
  هموگش ِ کوشی   
hamugeš-e Cauchy

Fr.: équation de Cauchy   

A relationship between the → refractive index (n) and the wavelength of light (λ) passing through a medium. It is commonly stated in the following form: n = A + B2 + C4, where A, B, and C are constants characterizing the medium. The two-component Cauchy equation is n = A + B2, from which the dispersion becomes dn/dλ = -2B3 showing that dispersion varies approximately as the inverse cube of the wavelength. The dispersion at 4000 A will be about 8 times as large as at 8000 Å.

Named after Augustin Louis Cauchy (1789-1857), French mathematician and physicist who found the first equation of dispersion in 1836; → equation.