Andre-Marie Ampere, French physicist and mathematician, c 1810.
© Science Museum / Science & Society Picture Library
Ampere (1775-1836) was the French mathematician and physicist whose name was given to the basic unit of electric current - the ampere or amp - in 1881, replacing the term 'weber'. He was celebrated for his contributions to electrodynamics. Hans Christian oersted (1777-1851) had demonstrated in 1820 that an electric current produced a magnetic field. Between 1820 and 1827 Ampere established the mathematical laws relating magnetic forces to electric currents. He became Profesor of Physics and Chemistry at Bourg in 1801 and Profesor of Mathematics at the Ecole Polytechnique in Paris in 1809.