Kirchhoff, Gustav Robert

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Kirchhoff, Gustav Robert (1824-87), German physicist, born in Königsberg (now Kaliningrad, Russia), and educated at the University of Königsberg. He was professor of physics at the universities of Breslau, Heidelberg, and Berlin. With the German chemist Robert Wilhelm Bunsen, Kirchhoff developed the modern spectroscope for chemical analysis. In 1860 the two scientists discovered the elements cesium and rubidium by means of spectrum analysis. Kirchhoff conducted important investigations of radiation heat transfer and also postulated two rules, now known as Kirchhoff's laws of networks, concerning the distribution of current in electric circuits.

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