Planck radiation law


Definition of Planck radiation law

  1. 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. 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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Origin and Etymology of planck radiation law

after Max K. E. L. Planck

Seen and Heard

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a brief usually trivial fact

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