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ampere
(A)
subjectfact 
amperehas symbol A2001-09-27 09:32:49.0
has consequence fixes the magnetic constant (permeability of vacuum) at exactly 4 × 10-7 H · m-12001-09-27 09:32:49.0
has definition Unit of electric current. "The ampere is that constant current which, if maintained in two straight parallel conductors of infinite length, of negligible circular cross-section, and placed 1 meter apart in vacuum, would produce between these conductors a force equal to 2 × 10-7 newton per meter of length" CIPM 1946, Resolution 2, approved by the 9th CGPM 1948). A current of 1 A is equivalent to the passage along the filament of a light bulb of about 6 × 1018 electronic charges per second.has source: Hopkins, J. 1976 Glossary of Astronomy and Astrophysics, University of Chicago Press, 2001-09-27 09:32:49.0
has definition constant current which, if maintained in two straight parallel conductors of infinite length, of negligible circular cross-section, and placed 1 meter apart in vacuum, would produce between these conductors a force equal to 2 × 10-7 newton per meter of length2001-09-27 09:32:49.0
is an instance of current unit2001-09-27 09:32:49.0
is an instance of base SI unit2001-09-27 09:32:49.0
current unitis a unit of current2001-09-27 09:32:49.0
SI unitis an acronym for Syteme Internationale2001-09-27 09:32:55.0
unithas historical origin2001-09-27 09:32:42.0
represents2001-09-27 09:32:42.0