ampere

or am·père

[ am-peer, am-peer ]

nounElectricity.
  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. Abbreviation: A, amp.

Origin of ampere

1
First recorded in 1881; named after A. M. Ampère

Other definitions for Ampère (2 of 2)

Ampère
[ am-peer; French ahn-per ]

noun
  1. An·dré Ma·rie [ahn-drey muh-ree; French ahn-dreyma-ree], /ˈɑn dreɪ məˈri; French ɑ̃ˈdreɪ maˈri/, 1775–1836, French physicist.

Other words from Ampère

  • Am·per·i·an [am-peer-ee-uhn, -per-], /æmˈpɪər i ən, -ˈpɛr-/, adjective

Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2024

How to use ampere in a sentence

  • A relay snapped, and instantly the ammeter jumped to read 4500 amperes.

    Islands of Space | John W Campbell
  • They even managed to get six hundred amperes through a piece of lead wire no bigger than a pencil lead.

    Islands of Space | John W Campbell
  • "Forty-five hundred amperes at twenty thousand volts," the elder Arcot said softly.

    Islands of Space | John W Campbell
  • Thus, if a coil is used that doubles the original number of amperes produced by the battery, the voltage will be halved.

    The Gasoline Motor | Harold Whiting Slauson
  • ampere—Amperes are units by which the rate of flow of electrical current (electrons) is measured.

British Dictionary definitions for ampere (1 of 2)

ampere

/ (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

Origin of ampere

1
C19: named after André Marie Ampère
  • Abbreviation: amp
  • Symbol: A

British Dictionary definitions for Ampère (2 of 2)

Ampère

/ (ˈæmpɛə, French ɑ̃pɛr) /


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

Collins English Dictionary - Complete & Unabridged 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012

Scientific definitions for ampere (1 of 2)

ampere

[ ămpîr′ ]


  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 X 1018 electrons per second.

Scientific definitions for Ampère (2 of 2)

Ampère

[ ămpîr′, 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.

The American Heritage® Science Dictionary Copyright © 2011. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.