The Stefan-Boltzmann Law

The total power per unit area from a blackbody radiator can be obtained by integrating the Planck radiation formula over all wavelengths. The radiated power per unit area as a function of wavelength is

so the integrated power is

It is helpful to make the substitution

Making the substitution gives

Making use of the standard form integral

gives the final form of the Stefan-Boltzmann law

Calculation of radiated power

Blackbody radiation concepts
HyperPhysics***** Thermodynamics R Nave
Go Back