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Explain Stefan-Boltzmann law

Stefan-Boltzmann law (Stefan, L. Boltzmann): The radiated power P (that is the rate of emission of electromagnetic energy) of a hot body is proportional to the radiating surface area, A, and the 4th power of the thermodynamic temperature, T. The constant of proportionality is Stefan-Boltzmann constant. Scientifically,

P = e sigma A T4,

Here the efficiency rating e is termed as the emissivity of the object.

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