StefanBoltzmann LawThe thermal energy radiated by a blackbody radiator per second per unit area is proportional to the fourth power of the absolute temperature and is given by For hot objects other than ideal radiators, the law is expressed in the form: where e is the emissivity of the object (e = 1 for ideal radiator). If the hot object is radiating energy to its cooler surroundings at temperature T_{c}, the net radiation loss rate takes the form The StefanBoltzmann relationship is also related to the energy density in the radiation in a given volume of space.

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Heat RadiationThermal radiation is energy transfer by the emission of electromagnetic waves which carry energy away from the emitting object. For ordinary temperatures (less than red hot"), the radiation is in the infrared region of the electromagnetic spectrum. The relationship governing the net radiation from hot objects is called the StefanBoltzmann law:
While the typical situation envisioned here is the radiation from a hot object to its cooler surroundings, the StefanBoltzmann law is not limited to that case. If the surroundings are at a higher temperature (T_{C} > T) then you will obtain a negative answer, implying net radiative transfer to the object.

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Radiation Calculation

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