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English definition of “Planck's constant”

Planck's constant

noun [U]  /ˈplæŋks ˈkɑn·stənt, ˈplɑŋks-/ us  
physics a number that never changes and that expresses the relationship between the energy of a photon and its frequency
(Definition of Planck's constant from the Cambridge Academic Content Dictionary © Cambridge University Press)
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