StefanBoltzmann Law


The StefanBoltzmann law states that the emissive power (E) from a black body is directly proportional to the forth power of its absolute temperature (T). 

i.e. E = σ x T^{4} 

Where, σ = StefanBoltzmann constant = 5.67E8 W / ( m^{2} K^{2} )


The law was experimentally discovered by Jozef Stefan ( 18351893
) in 1879 and theoretically derived in the frame of the thermodynamics
by Ludwig Boltzmann ( 18441906 ) in 1884. 

The emitted power (E) for a nonblack body with emissivity (ε) is


E = ε x σ x T^{4} 