Ohm, Georg Simon

born March 16, 1789, Erlangen, Bavaria

died July 6, 1854, Munich

German physicist.

While teaching mathematics at the Jesuits' College in Cologne (1817–27), he discovered that the flow of electric current through a conductor is directly proportional to the potential difference, or voltage, and inversely proportional to the resistance. He resigned when his theory (Ohm's law) was coldly received. His theory soon came to be widely recognized, and he subsequently taught in Nürnberg (1833–49) and Munich (1849–54). The physical unit measuring electrical resistance was named for him.

Ohm, detail of a lithograph

Historia-Photo

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▪ German physicist

born March 16, 1789, Erlangen, Bavaria [Germany]

died July 6, 1854, Munich

      German physicist who discovered the law, named after him, which states that the current flow through a conductor is directly proportional to the potential difference (voltage) and inversely proportional to the resistance.

      Ohm became professor of mathematics at the Jesuits' College at Cologne in 1817. The most important aspect of Ohm's law is summarized in his pamphlet Die galvanische Kette, mathematisch bearbeitet (1827; The Galvanic Circuit Investigated Mathematically). While his work greatly influenced the theory and applications of current electricity, it was so coldly received that Ohm resigned his post at Cologne. He accepted a position at the Polytechnic School of Nürnberg in 1833. Finally his work began to be recognized; in 1841 he was awarded the Copley Medal of the Royal Society of London and was made a foreign member a year later. The physical unit measuring electrical resistance was given his name.

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