Bright Sparks – Georg Ohm

The modern world would look very different without the contributions of those who helped us harness electricity and develop electrical equipment. Here, we focus on some of the pioneers of the electrical world and their remarkable achievements.

NAME: Georg Ohm

DATES: 16 March 1789 (Erlangen, Bavaria) – 6 July 1854 (Munich, Germany)

EARLY LIFE: Born into a Protestant family, Georg Simon Ohm was one of seven children, although only he, a sister and a brother survived childhood. Their father, a locksmith, home educated Georg and his brother Martin to an exceptionally high standard, in particular in maths and science, which led to Martin’s career as a mathematician and to Georg’s advances in electromagnetism.

At the University of Erlangen, Georg enjoyed the distractions of student life a little too much and his father insisted he leave for Switzerland. After working as a school teacher then private maths tutor, he returned to the University of Erlangen in 1811 as a lecturer, followed by more teaching posts in schools. While at the Jesuit Gymnasium of Cologne, he continued his studies and began experimental work based on Hans Christian Oersted’s 1820 discovery of electromagnetism.

FIRST PAPER: In 1825, Ohm published a paper looking at how electromagnetic force produced by a wire decreases in line with the increase in length of the wire.

MAJOR ACHIEVEMENTS:
Ohm’s Law: I = EIR

This formula describes the relationship between voltage, current and resistance in an electrical circuit, in that current is directly proportional to voltage and inversely proportional to resistance.

As a result the Ohm – a physical unit of electrical resistance – was named after him.

NOTABLE DATES:
1820s
1826 wrote two important papers, which offered a mathematical description of conduction and proposed laws about galvanic electricity. These were based on studies of heat conduction by the French mathematician Joseph Fourier.

1827 published his book: The Galvanic Circuit Investigated Mathematically (Die galvanische Kette, mathematisch bearbeitet), which first posited Ohm’s Law.

1830s
1833 became Professor of Mathematics and Physics at the Royal Polytechnic School of Nuremberg.

1839 became Chancellor of the Royal Polytechnic School of Nuremberg (until 1849).

1840s
1841 awarded the Copley Medal by the Royal Society of London.

1842 became a foreign member of the Royal Society.

1843 proposed a theory of sounds, which became known as Ohm’s Acoustic Law; however, this law is generally considered not to be completely accurate.

1845 made a member of the Bavarian Academy of Sciences and Humanities.

1849 became curator of the Bavarian Academy’s physical cabinet; lectured at the University of Munich; published the book Molecular Physics.

1854 appointed Chair of Physics at the University of Munich.

1854 died on 6 July, aged 65.

3 THINGS YOU MIGHT NOT KNOW:
1.    Ohm’s mother died when he was just 10 years old.
2.    While working at a new school set up in Cologne, Ohm spent a large part of his salary on new equipment for the physics laboratory.
3.    In 1850, Nuremberg awarded Ohm the Freedom of the Town.

LEGACY:
Although his education came largely from his self-taught father, Georg Ohm became a key figure the history of electromagnetism.

The publication of The Galvanic Circuit Investigated Mathematically was to have a major impact in the field, and his work formed the basis of circuit theory, which was to later prove a key area of research.