speed of light
noun phrase
: a fundamental physical constant that is the speed at which electromagnetic radiation propagates in a vacuum and that has a value fixed by international convention of 299,792,458 meters per second
—symbol c
Examples of speed of light in a Sentence
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This describes the relationship between a particle’s energy (E) and mass (m), with the speed of light (c) squared.
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Michael Irving, New Atlas, 11 Dec. 2024
The data also revealed details of a 300,000 light-year-long jet of material being expelled from the quasar at nearly the speed of light—approximately three times the width of our Milky Way galaxy, according to NASA.
—Paul Du Quenoy, Newsweek, 9 Dec. 2024
According to Einstein’s general relativity theory, these ripples travel at the speed of light, causing space itself to stretch and squeeze around them, kind of like a wave.
—Jonathan Zrake, Discover Magazine, 5 Dec. 2024
With more powerful and virulent tools, fake news can travel at near two thirds the speed of light, often without human regulation.
—Yaakov Katz, Newsweek, 27 Nov. 2024
See all Example Sentences for speed of light 
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Michael Irving, New Atlas, 11 Dec. 2024
The data also revealed details of a 300,000 light-year-long jet of material being expelled from the quasar at nearly the speed of light—approximately three times the width of our Milky Way galaxy, according to NASA.
—Paul Du Quenoy, Newsweek, 9 Dec. 2024
According to Einstein’s general relativity theory, these ripples travel at the speed of light, causing space itself to stretch and squeeze around them, kind of like a wave.
—Jonathan Zrake, Discover Magazine, 5 Dec. 2024
With more powerful and virulent tools, fake news can travel at near two thirds the speed of light, often without human regulation.
—Yaakov Katz, Newsweek, 27 Nov. 2024
See all Example Sentences for speed of light
Dictionary Entries Near speed of light
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“Speed of light.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/speed%20of%20light. Accessed 21 Dec. 2024.
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