Posted by John Oleinik on October 22, 1997 at 19:33:17:
In Reply to: I need info on Georg Simon Ohm posted by Erin on April 28, 1997 at 22:23:04:
Georg Ohm was born in Erlangen, Bavaria (which is now West Germany), on the sixteenth of March, 1789. He was the son of a master mechanical engineer, who taught him basic practical skills. While still young, Ohm's ambition was to become a scientist and to work at one of the great German Universities. He studied at the University of Erlangen, and at the age of 24 (1813), he began teaching physics and mathematics at the Realschule in Bamberg. He remained there for almost four years, before becoming a professor of mathematics for the Jesuit's college at Cologne in 1817.
Ohm's main interest was current electricity, which had recently advanced by Alessandro Volta's invention of the battery. Ohm made only a modest living, and as a result his experimental equipment was quite crude. Despite this, he made his own metal wire, producing a range of thicknesses and lengths of remarkably consistent quality. For the nine years he spent at the Jesuit's college, he did considerable experimental research on the nature of electric circuits. He took considerable pains to be brutally accurate with every detail of his work.
In 1827, he was able to show from his experiments that there was a simple relationship between resistance, current and voltage. His pamphlet Die galvanische Kette, mathematisch bearbeitet(The Galvanic Circuit Investigated Mathematically ), summarized his experimentally discovered law. Ohm's Law stated that the amount of steady current through a material is directly proportional to the potential difference, or voltage, across the material, for some fixed temperature. Mathematically expressed as I = V / R . He had discovered the distribution of electromotive force in an electrical circuit, and had established a definite relationship connecting resistance, electromotive force, and current strength. Ohm was afraid that the purely experimental basis of his work would undermine the importance of his discovery. He tried to state his law theoretically but his rambling mathematical proofs made him an object of ridicule. He was criticized so harshly that he was forced to resign his teaching post.
In the years that followed, Ohm lived in poverty, tutoring privately in Berlin. He would receive no credit for his findings until he was made director of the Polytechnic School of Nuremburg in 1833, six years after his resignation. In 1841, the Royal Society in London recognized the significance of his discovery and awarded him the Copley medal. The following year, they admitted him as a member. In 1849, just five years before his death, Ohm's lifelong dream was realized when he was given a professorship of experimental physics at the University of Munich. On July 7, 1854, he passed away in Munich, at the age of 65.
Ohm's Law has stayed the test of time, being proven true by J. Clerk Maxwell and George Chrystal, and it is now universally known and used in physics. His work lead to the unit of resistance to the flow of electricity through a conductor to be named after him, in 1893 by the International Electrical Congress. He also experimented with optics, acoustics, and the electrical conductivity of liquids, but he is mainly known for his work with galvanic circuits. "Ohm's work stands alone, and, reading it at the present time, one is filled with wonder at his presience, respect for his patience and prophetic soul, and admiration at the immensity and variety of ground covered by his little book, which is indeed his best monument."(Thomas Lockwood, 1891)
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Bibliography
Ohm, G. S. ; "The Galvanic Circuit Investigated Mathematically"; translated by William Francis; Kraus Reprint Co.; New York, 1969(original copyright 1891)
Encyclopedia Americana; Vol. 20, pg. 673; Groiler Inc., Danbury, CT, 1995
Encyclopaedia Britannica; Vol. VII, pg. 496; Benton, Publisher, 1974
Britannica Online, http://www.eb.com
I just got done with this project, so I'll help you out!