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• ampere
  ampere

  noun

  the basic unit of electrical current in the International System of Units (SI), equivalent to one coulomb per second, formally defined to be the constant current which if maintained in two straight parallel conductors of infinite length, of negligible circular cross section, and placed one meter apart in vacuum, would produce between these conductors a force equal to 2 × 10 −7 newton per meter of length. A, amp.
• Ampère
  Ampère

  noun

  André Marie 1775–1836, French physicist.

ampere

¹ American  

[am-peer, am-peer] / ˈæm pɪər, æmˈpɪər /

Or ampère

noun

Electricity.

1. the basic unit of electrical current in the International System of Units (SI), equivalent to one coulomb per second, formally defined to be the constant current which if maintained in two straight parallel conductors of infinite length, of negligible circular cross section, and placed one meter apart in vacuum, would produce between these conductors a force equal to 2 × 10 −7 newton per meter of length. A, amp.

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Ampère ² American  

[am-peer, ahn-per] / ˈæm pɪər, ɑ̃ˈpɛr /

noun

1. André Marie 1775–1836, French physicist.

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ampere ¹ British  

/ ˈæmpɛə /

noun

1. the basic SI unit of electric current; the constant current that, when maintained in two parallel conductors of infinite length and negligible cross section placed 1 metre apart in free space, produces a force of 2 × 10 ^–7 newton per metre between them. 1 ampere is equivalent to 1 coulomb per second

2. a former unit of electric current ( international ampere ); the current that, when passed through a solution of silver nitrate, deposits silver at the rate of 0.001118 gram per second. 1 international ampere equals 0.999835 ampere

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Ampère ² British  

/ ˈæmpɛə, ɑ̃pɛr /

noun

1. André Marie (ɑ̃dre mari). 1775–1836, French physicist and mathematician, who made major discoveries in the fields of magnetism and electricity

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Ampère ¹ Scientific  

/ ăm′pîr′,äm-pĕr′ /

1. French mathematician and physicist who is best known for his analysis of the relationship between magnetic force and electric current. He formulated Ampère's law, which describes the strength of the magnetic field produced by the flow of energy through a conductor. The ampere unit of electric current is named for him.

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ampere ² Scientific  

/ ăm′pîr′ /

1. The SI unit used to measure electric current. Electric current through any given cross-section (such as a cross-section of a wire) may be measured as the amount of electrical charge moving through that cross-section in one second. One ampere is equal to a flow of one coulomb per second, or a flow of 6.28 × 10 ¹⁸ electrons per second.

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Other Word Forms

• Amperian
  adjective

Etymology

Origin of ampere

First recorded in 1881; named after A. M. Ampère

Example Sentences

See Examples For:

ampere Ampère

We measure the charge that flows for a current of one ampere in one second.

From Textbooks ● Aug. 12, 2015

But you might not expect that the force between wires is used to define the ampere.

From Textbooks ● Aug. 12, 2015

The General Conference on Weights and Measures meets in Sèvres, near Paris, to discuss how to redefine the kilogram, ampere, kelvin and mole.

From Nature ● Oct. 12, 2011

A draft resolution to be considered at the General Conference of Weights and Measures in October includes new and improved definitions for the ampere, the mole and the candela.

From New York Times ● Feb. 12, 2011

Turn on a hundred lamps connected to the same wires, and the dynamo of its own accord keeps the pressure the same, and supplies fifty amperes, or half an ampere for each lamp.

From The Story of Great Inventions by Elmer Ellsworth Burns

Renault intends to remain the majority shareholder in its "Ampère" electrical division, which will employ around 10,000 people and could list on the stock market in the second half of 2023.

From Reuters ● Aug. 31, 2022

She had privileged status at sites from the Paris Observatory to the National Museum of Natural History, and in the laboratories of electrical-theory pioneers André-Marie Ampère and Antoine César Becquerel.

From Nature ● Oct. 21, 2014

The discoveries of Ampère as to the laws of electricity have been likened to the discovery of Newton of the law of gravitation.

From Inventions in the Century by William Henry Doolittle

Among the famous people who died in 1836 were Aaron Burr, ex-President James Madison, James Hogg, Scottish poet; André Ampère, French scientist, and Mme.

From The Scrap Book, Volume 1, No. 4 June 1906 by Various

Figure 2.—“Galvanometer” was the name given by Bischof to this goldleaf electrostatic instrument in 1802, 18 years before Ampère coupled the word with the use of Oersted’s electromagnetic experiment as an indicating device.

From The Earliest Electromagnetic Instruments by Robert A. Chipman