photoelectric effect


: the emission of free electrons from a metal surface when light strikes it

Example Sentences

Recent Examples on the Web Two years later, Einstein won the Nobel Prize in Physics, not for general relativity, but for his discovery of the photoelectric effect. Mark Barna, Discover Magazine, 16 Dec. 2022 Other papers that year were on Brownian motion, suggesting the existence of molecules and atoms, and the photoelectric effect, showing that light is made of particles later called photons. Mark Barna, Discover Magazine, 16 Dec. 2022 Albert Einstein explains the photoelectric effect—shining light on certain materials can function to release electrons from the material—and suggests that light itself consists of individual quantum particles or photons. Gil Press, Forbes, 18 May 2021 Albert Einstein proposed a theory of the photoelectric effect in 1905, describing the phenomenon in which electrons can be ejected from atoms after they are hit by light. NBC News, 19 Oct. 2020 One of the most recognizable names appearing in the auction is that of Albert Einstein, who developed the theory of relativity and won the 1921 Nobel Prize in Physics for his discovery of the photoelectric effect. Theresa Machemer, Smithsonian Magazine, 10 July 2020 Genius is an in-depth dramatic look at the life and career of the theoretical physicist who, among other things, explained the photoelectric effect that made the invention of television possible. Darryn King, HWD, 24 Apr. 2017 See More

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

Word History

First Known Use

1892, in the meaning defined above

Time Traveler
The first known use of photoelectric effect was in 1892

Dictionary Entries Near photoelectric effect

Cite this Entry

“Photoelectric effect.” Dictionary, Merriam-Webster, Accessed 23 Mar. 2023.

Kids Definition

photoelectric effect

: the giving off of free electrons from a metal surface when light strikes it

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