*h*) which gives the ratio of a quantum of radiant energy (

*E*) to the frequency (?) of its source: it is expressed by the equation

*E*=

*h*?, and its approximate numerical value is 6.626 × 10 joule second

Origin of Planck's constant

after PlanckPhysics a universal constant (*h*) which gives the ratio of a quantum of radiant energy (*E*) to the frequency (?) of its source: it is expressed by the equation *E* = *h*?, and its approximate numerical value is 6.626 × 10 joule second

often Planck constant

Origin of Planck's constant

after PlanckWebster's New World College Dictionary, Fifth Edition Copyright © 2014 by Houghton Mifflin Harcourt Publishing Company. All rights reserved.

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"Planck\'s constant." YourDictionary, n.d. Web. 12 December 2018. <https://www.yourdictionary.com/planck-s-constant>.

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Planck\'s constant. (n.d.). Retrieved December 12th, 2018, from https://www.yourdictionary.com/planck-s-constant

noun

The constant of proportionality relating the energy of a photon to the frequency of that photon. Its value is approximately 6.626 × 10^{−34} joule-seconds.

Origin of Planck's constant

AfterMax Karl Ernst LudwigTHE AMERICAN HERITAGE® DICTIONARY OF THE ENGLISH LANGUAGE, FIFTH EDITION by the Editors of the American Heritage Dictionaries. Copyright © 2016, 2011 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.

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"Planck\'s constant." YourDictionary, n.d. Web. 12 December 2018. <https://www.yourdictionary.com/planck-s-constant>.

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Planck\'s constant. (n.d.). Retrieved December 12th, 2018, from https://www.yourdictionary.com/planck-s-constant

A physical constant that is used extensively in quantum mechanics and fixes the scale of quantization of many phenomena, such as the relation between the energy of a photon (a quantum of light) and its wavelength. Its value is approximately 6.626 × 10^{-34} joule-seconds (equivalent to units of angular momentum). Planck's constant is fundamental to phenomena as the quantization of angular momentum and is used in Heisenberg's Uncertainty Principle.

See also Dirac's constant

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"Planck\'s constant." YourDictionary, n.d. Web. 12 December 2018. <https://www.yourdictionary.com/planck-s-constant>.

**APA Style**

Planck\'s constant. (n.d.). Retrieved December 12th, 2018, from https://www.yourdictionary.com/planck-s-constant

Noun

- (physics) the constant of proportionality (symbol
*h*), relating the energy and frequency of a photon (6.626 x 10^{-34}joule-seconds); also related to the indeterminacy limit in the Heisenberg uncertainty principle; the quantum of action

Origin

Named for Max Planck (1858-1947), German theoretical physicist, who discovered it in 1900.

English Wiktionary. Available under CC-BY-SA license.

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- Planck's constant
- planck-scale
- planck-speed
- planck-temperature