Stefan-Boltzmann

Stefan–Boltzmann law:

The total energy per unit time, per unit surface area, E, given off by a blackbody is proportional to the fourth power of the temperature. The T4 dependence means that E depends strongly on T.

\[E=\sigma T^4\]

This relationship is called the Stefan–Boltzmann law. The constant of proportionality, σ, is called the Stefan–Boltzmann constant. It has a value of 5.7 × 10–5 erg/(cm2 K4 s). This law was first determined experimentally, but it can also be derived theoretically.