specific impulse

noun

Definition of specific impulse

: the thrust produced per unit rate of consumption of the propellant that is usually expressed in pounds of thrust per pound of propellant used per second and that is a measure of the efficiency of a rocket engine

Examples of specific impulse in a Sentence

Recent Examples on the Web This would be a monumental achievement given that the world-record specific impulse—held by NASA—is 542 seconds, and most operating orbital rockets have specific impulses around 300 seconds. Daniel Oberhaus, Ars Technica, "The rocket motor of the future “breathes” air like a jet engine," 27 June 2020 This would be a monumental achievement given that the world-record specific impulse—held by NASA—is 542 seconds, and most operating orbital rockets have specific impulses around 300 seconds. Daniel Oberhaus, Ars Technica, "The rocket motor of the future “breathes” air like a jet engine," 27 June 2020 This would be a monumental achievement given that the world-record specific impulse—held by NASA—is 542 seconds, and most operating orbital rockets have specific impulses around 300 seconds. Daniel Oberhaus, Ars Technica, "The rocket motor of the future “breathes” air like a jet engine," 27 June 2020 This would be a monumental achievement given that the world-record specific impulse—held by NASA—is 542 seconds, and most operating orbital rockets have specific impulses around 300 seconds. Daniel Oberhaus, Wired, "The Rocket Motor of the Future Breathes Air Like a Jet Engine," 26 June 2020 The shorter engine nozzle would cost SpaceX a small hit on the upper stage’s performance, with a decreased specific impulse. Eric Berger, Ars Technica, "Forget Dragon, the Falcon 9 rocket is the secret sauce of SpaceX’s success," 3 June 2020 But what was the specific impulse that led you to tell Berg’s story? Andrew Silow-carroll, sun-sentinel.com, "Moe Berg’s life as ballplayer and spy presented in documentary," 4 June 2019 Liquid hydrogen, by contrast, has a really high specific impulse. Eric Berger, Ars Technica, "After a decade of testing, propylene rocket fuel may be ready for prime time," 25 Sep. 2018 Never used before in a larger engine, propylene has useful properties of higher density and specific impulse that will give Vector's small rocket more performance. Eric Berger, Ars Technica, "Rocket Report: SpaceX gets Moon launches, South Korean rocket, BE-4 wins," 28 Sep. 2018

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'specific impulse.' 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 specific impulse

1947, in the meaning defined above

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The first known use of specific impulse was in 1947

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Last Updated

11 Oct 2020

Cite this Entry

“Specific impulse.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/specific%20impulse. Accessed 23 Oct. 2020.

More from Merriam-Webster on specific impulse

Britannica.com: Encyclopedia article about specific impulse

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