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Stefan-Boltzmann Law

\LARGE J={\sigma}T^4

The Terms

J - Energy radiated per unit area of a black body per unit time [Units: J m-2 s-1]

\sigma - Stefan-Boltzmann constant [Value: 5.67 x 10-8 J s-1 m-2 K-4]

T - Absolute temperature [Units: K]

What Does It Mean?

This law states that the energy radiated from a black body is proportional to the fourth power of the absolute temperature. A black body is one which absorbs and emits radiation at all frequencies, with characteristic continuous emission spectra. 

Further information at Warwick

The Stefan-Boltzmann Law is covered in the first year module "PX101 Quantum Phenomena". 


Jožef Stefan