Theory
It may be shown by electromagnetic theory, by quantum theory, or by thermodynamics, making no assumptions as to the nature of the radiation, that the pressure against a surface exposed in a space traversed by radiation uniformly in all directions is equal to one third of the total radiant energy per unit volume within that space.
Quantitatively, this can be expressed as
,
for a radiation energy density, at a temperature . Here, the radiation constant, where is the Stefan-Boltzmann constant, and is the speed of light.
Read more about this topic: Radiation Pressure
Famous quotes containing the word theory:
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—Rheta Childe Dorr (1866–1948)
“Lucretius
Sings his great theory of natural origins and of wise conduct; Plato
smiling carves dreams, bright cells
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“Frankly, these days, without a theory to go with it, I can’t see a painting.”
—Tom Wolfe (b. 1931)