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Beer's law of attenuation of light in a medium is closely related to the Lambert law. It states:
| c = n cn | (1) |
where c [length-1] is the attenuation coefficient of the medium, n is the concentration of the attenuating agent, and cn is the concentration specific attenuation coefficient of the medium, respectively. The Beer law has been named after A. Beer (1825-1863, see, for example, http://en.wikipedia.org/wiki/August_Beer who published his findings in 1854.
If n is the mass concentration [mass length-3] then cn has a dimension of length2 mass-1. If n is defined as the number concentration of particles [length-3], then cn becomes the particle attenuation cross section.
When combined with the Lambert law, the Beer law is referred to as the Lambert-Beer or Beer-Lambert law:
| T(z) = e -n cn z | (2) |
where T is the transmission of light.
See also Beer's law for dense aquatic dispersions
| CITATION: Jonasz M. 2006. Beer's law (www.tpdsci.com/Tpc/BeerLw.php). In: Top. Part. Disp. Sci. (www.tpdsci.com). |
HISTORY: Published: 17-Jan-2006 Modified: 25-Oct-2007 Peer-reviewed: 06-Dec-2006 |
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