alternating current


Definition of alternating current

: an electric current that reverses its direction at regularly recurring intervals abbreviation AC

Examples of alternating current in a Sentence

Recent Examples on the Web Frequent fast-charging (direct current) also took a toll compared to slower Level 1 or 2 charging (alternating current at 120 and 240 volts). Michael J. Coren, Quartz, "Fast charging is not a friend of electric car batteries," 15 Dec. 2019 For those accustomed to thinking of Generac — a name derived from its generators producing alternating current, or A.C. — as the maker of emergency generators, the change might seem surprising. Jim Riccioli, Milwaukee Journal Sentinel, "Generac moves toward clean-energy option for homes," 24 Dec. 2019 But Tesla had the last laugh, because today, alternating current is predominantly used to power most of the world's electricity. Lauren Kent, CNN, "The Nikola Tesla inventions that should have made the inventor famous, such as the 'teleautomaton,' 'shadowgraphs' and possibly a death ray," 25 Oct. 2019 The electricity that comes out of a wall outlet is an alternating current (AC) and needs to be converted to direct current (DC) to operate your devices. David Kender, USA TODAY, "Myth vs. fact: Unplugging devices when you leave the house," 27 Nov. 2019 For instance, Edison's propaganda machine did indeed pump out hundreds of flyers and pamphlets on the dangers of alternating current, even electrocuting animals in front of newspaper reporters. Jennifer Ouellette, Ars Technica, "The “original disruptors” go head to head in The Current War: Director’s Cut," 25 Oct. 2019 Building on his vision in Budapest, Tesla now experimented with using several alternating currents in his motor. National Geographic, "Edison and Tesla's cutthroat 'Current War' ushered in the electric age," 27 Sep. 2019 But the players maintained their assiduous fire, plugged into the alternating current of past and present. Matthew Guerrieri, Washington Post, "Claremont Trio energetically amplifies historical currents," 16 Dec. 2019 The man was Nikola Tesla, inventor of the alternating current (AC) motor. National Geographic, "Edison and Tesla's cutthroat 'Current War' ushered in the electric age," 27 Sep. 2019

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'alternating current.' Views expressed in the examples do not represent the opinion of Merriam-Webster or its editors. Send us feedback.

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First Known Use of alternating current

1833, in the meaning defined above

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Time Traveler for alternating current

Time Traveler

The first known use of alternating current was in 1833

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Statistics for alternating current

Cite this Entry

“Alternating current.” Dictionary, Merriam-Webster, Accessed 4 Jul. 2020.

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More Definitions for alternating current

alternating current


English Language Learners Definition of alternating current

: an electric current that changes its direction very frequently at regular intervals

alternating current


Kids Definition of alternating current

: an electric current that reverses its direction of flow regularly many times per second

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More from Merriam-Webster on alternating current

Spanish Central: Translation of alternating current

Nglish: Translation of alternating current for Spanish Speakers Encyclopedia article about alternating current

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