# Planck's radiation law

- the law that energy associated with electromagnetic radiation, as light, is composed of discrete quanta of energy, each quantum equal to Planck's constant times the corresponding frequency of the radiation: the fundamental law of quantum mechanics.
- the law giving the spectral distribution of radiation from a blackbody.

## Origin of Planck's radiation law^{}

First recorded in 1905–10; named after M. K. E. Planck

Also called Planck radiation formula, Planck's law.

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Based on the Random House Unabridged Dictionary, © Random House, Inc. 2018