n 1  :  the practical mks unit of electric current that is equivalent to a flow of one coulomb per second or to the steady current produced by one volt applied across a resistance of one ohm  2  :  the base unit of electric current in the International System of Units that is equal to a constant current which when maintained in two straight parallel conductors of infinite length and negligible circular sections one meter apart in a vacuum produces between the conductors a force equal to 2 × 10^-7newton per meter of length
 
Am•père, André Marie (1775-1836), French physicist. Ampère is credited with founding, naming, and developing the science of electrodynamics. He was the formulator of two laws in electromagnetism relating magnetic fields to electric currents. The first person to develop techniques for measuring electricity, he invented an instrument that was a forerunner of the galvanometer. In 1881 at the suggestion of Sir Charles Bright, an international congress on electricity adopted ampere as a term for the standard unit of electric current.
 
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