Stefan-Boltzmann Constant

Written by Jerry Ratzlaff on . Posted in Classical Mechanics

Stefan-Boltzmann constant, abbreviated as \( \sigma\)  (Greek symbol sigma), is the total intensity ratiated over all wavelength increases as the temperature increases.

 

Stefan-Boltzmann Constant formula

\(\large{ \sigma =  \frac{ 2\; \pi^5 \; k_b^4 }{ 15 \; h^3 \; c^2 }    }\) 

Where:

 Units English SI
\(\large{ \sigma }\)  (Greek symbol sigma) = Stefan-Boltzmann constant \(\large{\frac{Btu}{ft^2\;hr\; R^4}}\) \(\large{ \frac{W}{m^2-K^4} }\)
\(\large{ k_b }\) = Boltzmann constant \(\large{ \frac{lbm-ft^2}{sec^2} }\) \(\large{ \frac{kJ}{molecule-K} }\)
\(\large{ \pi }\) = Pi \(\large{3.141 592 653 ...}\)
\(\large{ h }\) = Planck's constant \(\large{ \frac{lbf-ft}{sec} }\) \(\large{ J-s }\)
\(\large{ c }\) = speed of light in vacuum \(\large{ \frac{ft}{sec} }\) \(\large{ \frac{m}{s} }\)

 

Stefan-Boltzmann Constant

\(\large{ \sigma = 1.713441 \;x\; 10^{-9}     \frac{Btu}{ft^2 \; hr \; R^4}}\) 
\(\large{ \sigma = 5.670374419 \;x\;10^{-8} \;\frac{W}{m^2 \; K^4}  }\)

 

 

Tags: Equations for Temperature Equations for Constant