Planck radiation law


Definition of Planck radiation law

1 : a law in physics: radiant energy arising from processes within atoms or molecules is emitted in finite quanta each of which is equal to the product of the radiation frequency by a universal constant h — see planck constant
2 : a law in physics: the energy density of radiation within a blackbody cavity at absolute temperature T in terms of the wavelength λ is given by ΔPλ = (8πhc)/λ5[ehc/(KλT) - 1]) Δλ where ΔPλ is the energy density within a given small wavelength interval Δλ, h is the Planck constant, and c the speed of light, all quantities being in cgs units

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History and Etymology for Planck radiation law

after Max K. E. L. Planck

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Cite this Entry

“Planck radiation law.” The Dictionary, Merriam-Webster Inc., Accessed 11 December 2019.

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heavy with or as if with moisture

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