Formula for Stefan-Boltzmann Law

Mathematically, Stefan Boltzmann’s law for the black body is given by 

P/A ∝T4

OR

P = σAT4

Where, 

  • P is the power radiated, 
  • A is the surface area of the black body, 
  • T is the temperature of the body and
  • σ is the Stefan-Boltzmann constant.

Objects which are not black bodies emit less radiation as they can absorb radiation as well. For such objects, Stefan Boltzmann’s law is as follows:

P/A ∝ eT4

OR

P = σeAT4

Where, e is the emissivity of the object and can have value from 0 to 1.

Stefan-Boltzmann Law

Stefan-Boltzmann Law relates the power radiated by the black body to its temperature and surface area. In the study of thermodynamics and astrophysics, the Stefan-Boltzmann Law is widely used to better our understanding of the subject. Other than this, Stefan-Boltzmann Law helps scientists understand the behavior of objects that emit radiation, such as stars and planets. Stefan-Boltzmann Law also has some applications in the real world as well such as, in designing solar panels and other energy conversion instruments.

Table of Content

  • What is Stefan-Boltzmann Law?
  • Formula for Stefan-Boltzmann Law
  • Stefan-Boltzmann Constant
  • Value of Stefan-Boltzmann Constant
  • Formula for Stefan-Boltzmann Constant
  • Black Body Radiation
  • Planck’s Law for Black Body Radiation
  • Derivation of Stefan-Boltzmann Constant
  • Calculation of Stefan-Boltzmann Constant
  • Applications of Stefan-Boltzmann Law
  • Sample Problems on Stefan-Boltzmann Law

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