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

Edison's propaganda machine pumped out hundreds of flyers and pamphlets on the dangers of alternating current, even electrocuting small animals in front of newspaper reporters. Jennifer Ouellette, Ars Technica, "AC/DC: It’s Tesla duking it out with Edison in The Current War trailer," 27 June 2019 All across the United States, the power grid operates at 60 hertz, its innumerable tributaries of alternating current synchronizing of their own accord. Quanta Magazine, "Scientists Discover Exotic New Patterns of Synchronization," 4 Apr. 2019 In one membrane, the wire had an alternating current applied to periodically heat it. Chris Lee, Ars Technica, "Edge on cooling from nanostructure beats physical limit," 11 Sep. 2018 Financial naiveté: The industrialist George Westinghouse financed the building of Tesla’s motor and alternating current system, buying Tesla’s patents in exchange for a lucrative royalty agreement. John F. Wasik, WSJ, "Lessons From Tesla (the Man, Not the Car)," 14 Sep. 2018 As demand increases, the line frequency of the electrical grid—the oscillation of alternating current over the wire—decreases. Sean Gallagher, Ars Technica, "Just say no: Wi-Fi-enabled appliance botnet could bring power grid to its knees," 17 Aug. 2018 The night before the event, the organizers realized that the hotel's electric supply was direct current and the ranges required alternating current. Judy Buchenot, Naperville Sun, "Suburban Cooks: Mints go from trash to treasured cookies," 13 July 2018 George Westinghouse was mainly responsible for the U.S.’s adoption of electric power transmission using the alternating current. Thomas Gryta, WSJ, "Why Thomas Edison Would Not Be Happy About GE’s Latest Deal," 23 May 2018 During the night, workers cut a hole in the hotel's wall, dropped a cable four stories to the street below and then pulled the cable through a manhole to the New York Central Railway, which used alternating current. Judy Buchenot, Naperville Sun, "Suburban Cooks: Mints go from trash to treasured cookies," 13 July 2018

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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Statistics for alternating current

Last Updated

16 Jul 2019

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Time Traveler for alternating current

The first known use of alternating current was in 1833

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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

Comments on alternating current

What made you want to look up alternating current? Please tell us where you read or heard it (including the quote, if possible).


to form ideas or theories about something

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