E=\sigma ({{T}^{4}})\]Þ \[\sigma =\frac{E}{{{T}^{4}}}\] where,\[E=\] \[\frac{\
TEXT
{
ENERGY
}}{\text{
AREA
}\
TIMES
\text{Time}}\] \[=\frac{\text{Watt}}{{{m}^{\text{2}}}}\] \[\sigma =\frac{\text{Watt-}{{m}^{-2}}}{{{K}^{4}}}=Watt-{{m}^{-2}}{{K}^{-4}}\]