André Marie Ampère

André Marie Ampère (1775-1836), French scientist, known for his important contributions to the study of electrodynamics. Ampère, the son of a Lyon city official, was born in Polémieux-au-Mont-d'Or, near Lyon. The ampere, the unit of electric current, is named after him. His electrodynamic theory and his views on the relationship of electricity and magnetism were published in his Recueil d'observations électrodynamiques (Collection of Observations on Electrodynamics, 1822) and in his Théorie des phénomènes électrodynamiques (Theory of Electrodynamic Phenomena, 1826). Ampère invented the astatic needle, which made possible the modern astatic galvanometer (see Electric Meters). He was the first to show that two parallel conductors carrying currents traveling in the same direction attract each other and, if traveling in opposite directions, repel each other.