Georg Ohm

Georg Ohm was a German physicist and mathematician whose 1827 statement of the linear relation between voltage, current and resistance — Ohm's law — is one of the foundational results of electrical theory. He was born Georg Simon Ohm on March 16, 1789, in Erlangen, in the Margraviate of Brandenburg-Bayreuth (now part of Bavaria), the son of a self-educated locksmith who taught his children mathematics and physics at home.

He entered the University of Erlangen in 1805, took his doctorate in 1811 with a dissertation on light and color, and spent the following years teaching mathematics in secondary schools, first in Bamberg and from 1817 at the Jesuit Gymnasium in Cologne. The Cologne school's well-equipped physics laboratory allowed him to perform the experiments on electrical conduction in metallic wires that were the basis of his later work.

He published his results in 1825 and 1826 and gathered them in the 1827 book Die galvanische Kette, mathematisch bearbeitet ("The Galvanic Circuit Investigated Mathematically"), in which he stated that the current through a conductor between two points is proportional to the voltage across the two points and inversely proportional to the resistance. The work was poorly received in Germany and his appointment to a professorship was delayed for a decade.

His reputation was secured by the recognition of his work in Britain — the Royal Society awarded him the Copley Medal in 1841 and elected him a foreign member in 1842. He was appointed professor of physics at the Polytechnic School of Nuremberg in 1833 and at the University of Munich in 1849, where he served as conservator of the physics cabinet of the Bavarian Academy of Sciences. He died in Munich on July 6, 1854. The SI unit of electrical resistance, the ohm, was named in his honor in 1881.

His name Georg is the German form of George, from the Greek Geōrgios meaning "farmer" or "earthworker" — from gē ("earth") and ergon ("work"). It is a masculine name long current in German-speaking countries.