Andre-Marie Ampere, French physicist and mathematician, c 1820.
© Science Museum / Science & Society Picture Library
Etching by F Tonnelat of the French physicist and mathematician Andre-Marie Ampere (1775-1836). Hans Christian oersted's (1777-1851) discovery that an electric current generates a magnetic field stimulated Ampere to investigate electric current and electrodynamics. His most significant contribution was the mathematical formulation of magnetism, known as Ampere's law, which he provided in 1827. The SI (the international system of standard scientific units) unit of electric current was named in his honour in 1881, replacing the term 'weber'. He became Profesor of Physics and Chemistry at Bourg in 1801 and Profesor of Mathematics at the Ecole Polytechnique in Paris in 1809. Published by the International Telecommunication Union.