Lambert, Johann

Lambert, Johann Heinrich (1728-1777) Swiss-born mathematician, physicist and astronomer in Augsburg and Berlin he studied hght intensity and also developed a theory of the generation of the universe that was similar to the nebular hypothesis that Thomas Wright and Immanuel Kant had (independently) developed. 

The second relationship is Lambert s law, (named after the German physicist Johann Heinrich Lambert) which states that the intensity of a beam of parallel, monochromatic light decreases exponentially as the light travels through a thickness of homogeneous medium , expressed mathematically as... 

Johann Heinrich Lambert (1728-1777), mathematician, physicist and philosopher, was a tutor for the Earl P. v. Salis in Chur from 1748-1759, where he wrote his famous work on photometry [5.2]. In 1759 he became a member of the Bavarian Academy of Science and upon proposal by L. Euler became a member of the Berlin Academy of Science in 1765. Lambert wrote several philosophical works and dealt with subjects from all areas of physics and astronomy in his numerous publications. He presented the absolute zero point as a limit in the expansion of gases and constructed several air thermometers. In 1761 he proved that v and e are not rational numbers. His works on trigonometry were particularly important for the theory of map construction. 

Wilhelm Beer and Johann Lambert independently proposed that at a given wavelength, the absorbance of a sample depends on the amount of absorbing species that the light encounters as it passes through a solution of the sample. In other words, absorbance depends on both the concentration of the sample and the length of the light... 

The way in which light is ahsorhed was studied hy Johann Heinrich Lambert (1728-1777), who first expressed it in the differential form,... 

Due to the interaction of solar radiation with molecules and particles of the atmosphere, the radiant flux decreases with the path x through the atmosphere (Fig. 2.12). Johann Heinrich Lambert showed in 1760 that the reduction of light intensity is proportional to the length of path x (or layer thickness) and the light (radiant flux) itself, A = x E, from which we derive the equation fIF... 

Lambert, J. H., Neues Organon,oder Gedanken uber die Erforschung und Bezeichnung des Wahren und dessen Unterscheidung von Irrthum und Schein I, II, Leipzig, Johann Wendler, 1764... 

Lambert lam-b9rt [Johann H. Lambert t 1777 German physicist philosopher] (1915) n. A deprecated unit of illumination equal to llm/cm. The SI unit is the lux (lx), equal to Ihn/m, i.e., 10 lambert. See also luminous flux. 

Johann Heinrich Lambert (1728-1777) Swiss mathematician, physicist, and astronomer Berlin, Germany, t August Beer (1825-1863) German physicist and mathematician Bonn, Germany. 

It is often found, within certain concentration limits, that the intensity of the absorption is proportional to both the concentration, c (mole per liter), and the thickness, / (centimeter), of the sample in the beam that is, the absorbance = tic, where e is defined as the molar extinction coeffident. This relationship is referred to as Beer s law or the Beer Lambert law. The law is named after August Beer (1825-1863), a lecturer in Bonn who studied optics, and Johann H. Lambert (1728-1777), a Swiss mathematician. It has been suggested that Beer s law was initially discovered by the French mathematician Pierre Bouguer (1698-1758). Lambert made reference (with attribution) to it and, much later, Beer extended it to its present form. 

Equations (1.1) and (1.2) are statements of Beer s law, or more accurately, the Beer-Lambert law. Johann Lambert, a physicist, mathematician and astronomer bom in 1728, observed that the fraction of the light that is transmitted IHo) is independent of Wilhelm Beer, a banker and astronomer who lived from 1797 to 1850, noted the exponential dependence on C. 

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