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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According to the researchers, the distance ensured that no information could travel between the chips during measurements, even at the speed of light, preventing interference with the randomness.
—
Neetika Walter, Interesting Engineering, 27 May 2026
No object can reach or exceed the speed of light (roughly 186,000 miles or 300,000 kilometers per second).
—Kai James, The Conversation, 26 May 2026
Today, a single optical fiber in modern submarine cables can carry data equivalent to roughly 150 million simultaneous phone calls at the speed of light, according to the International Cable Protection Committee.
—Mostafa Salem, CNN Money, 17 May 2026
Yes, radio waves are just light, and light can self-propagate through empty space—at the speed of light, as a matter of fact.
—Rhett Allain, Wired News, 15 May 2026
See All Example Sentences for speed of light
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Neetika Walter, Interesting Engineering, 27 May 2026
No object can reach or exceed the speed of light (roughly 186,000 miles or 300,000 kilometers per second).
—Kai James, The Conversation, 26 May 2026
Today, a single optical fiber in modern submarine cables can carry data equivalent to roughly 150 million simultaneous phone calls at the speed of light, according to the International Cable Protection Committee.
—Mostafa Salem, CNN Money, 17 May 2026
Yes, radio waves are just light, and light can self-propagate through empty space—at the speed of light, as a matter of fact.
—Rhett Allain, Wired News, 15 May 2026
See All Example Sentences for speed of light
Cite this Entry
“Speed of light.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/speed%20of%20light. Accessed 5 Jun. 2026.
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