John Hopkinson

John Hopkinson
Born	(1849-07-27)27 July 1849 Manchester, England
Died	27 August 1898(1898-08-27) (aged 49) Val d'Herens, Switzerland
Nationality	British
Known for	Hopkinson effect Hopkinson's law Hopkinson's test Three-phase electric power
Awards	Royal Medal (1890)
Scientific career
Fields	physics, electrical engineering

John Hopkinson, FRS, (27 July 1849 – 27 August 1898) was a British physicist, electrical engineer, Fellow of the Royal Society and President of the IEE (now the IET) twice in 1890 and 1896. He invented the three-wire (three-phase) system for the distribution of electrical power, for which he was granted a patent in 1882. He also worked in many areas of electromagnetism and electrostatics, and in 1890 was appointed professor of electrical engineering at King's College London, where he was also director of the Siemens Laboratory.^[1]

Hopkinson's law, the magnetic counterpart to Ohm's law, is named after him.