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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For nearby objects, the speed of light is great enough that the difference in time between source-and-observer can be neglected in most cases.
—
Ethan Siegel, Big Think, 2 Oct. 2025
While the Joliot-Curies were bombarding their samples with alpha particles at relatively low speeds, the Michigan State facility can accelerate stable isotopes up to half the speed of light and smash them on a target to produce new radioisotopes.
—Andrea Richard, The Conversation, 2 Oct. 2025
The study shows how scientists can essentially turn fiber optic cables into seismometers that return detailed data about earthquakes at the speed of light.
—Evan Bush, NBC news, 25 Sep. 2025
Additionally, this quasar is also producing jets of particles moving at nearly the speed of light, a rare feature among quasars.
—Rupendra Brahambhatt, Interesting Engineering, 21 Sep. 2025
See All Example Sentences for speed of light
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Ethan Siegel, Big Think, 2 Oct. 2025
While the Joliot-Curies were bombarding their samples with alpha particles at relatively low speeds, the Michigan State facility can accelerate stable isotopes up to half the speed of light and smash them on a target to produce new radioisotopes.
—Andrea Richard, The Conversation, 2 Oct. 2025
The study shows how scientists can essentially turn fiber optic cables into seismometers that return detailed data about earthquakes at the speed of light.
—Evan Bush, NBC news, 25 Sep. 2025
Additionally, this quasar is also producing jets of particles moving at nearly the speed of light, a rare feature among quasars.
—Rupendra Brahambhatt, Interesting Engineering, 21 Sep. 2025
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 16 Oct. 2025.
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