The practical unit of electrical current; the absolute, practical a. originally was defined as having the value of 110 of the electromagnetic unit (see abampere and coulomb). Present definitions are: 1. The practical unit of electrical current; the absolute, practical a. originally was defined as having the value of 110 of the electromagnetic unit (see abampere and coulomb). 2. Legal definition : the current that, flowing for 1 second, will deposit 1.118 mg of silver from silver nitrate solution. 3. Scientific (SI) definition : the current that, if maintained in two straight parallel conductors of infinite length and of negligible circular cross-sections and placed 1 m apart in a vacuum, produces between them a force of 2 × 10−7 N/m of length. [A. Ampère]
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am·pere 'am-.pi(ə)ralso -.pe(ə)r 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 × 10-7 newton per meter of length
Am·père än-per 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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n.
the basic SI units of electric current. It is equal to the current flowing through a conductor of resistance 1 ohm when a potential difference of 1 volt is applied between its ends. The formal definition of the ampere is the current that when passed through two parallel conductors of infinite length and negligible cross section, placed 1 metre apart in a vacuum, produces a force of 2 x 10-7 newton per metre between them. Symbol: A.
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am·pere (A) (amґpēr) [Andrй M. Ampиre, 1775–1836] the base SI unit of electric current, defined as the constant current that if maintained in two parallel straight conductors (of infinite length and negligible circular cross section) separated by a distance of 1 meter in a vacuum, produces a force between the conductors of 2 Ч10−7 newton per meter of length; it is equivalent to one coulomb per second. Formerly abbreviated amp.Medical dictionary. 2011.