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Heattransferoccursbyconduction,convectionandradiationExperiment:Stefan-Boltzmann'slawofradiationTheStefan-BoltzmannLawrelatesthefluxdensity, orthepowerperunitarea,radiatedbyanobjecttoT,theabsolutetemperatureoftheobject.RecommendedGroupSize.Introduction.Shortdescription.(He studiedthelightfromaheatedplatinumwire,whichbehavesapproximatelylikeablackbody)Stefan-BoltzmannRadiationLawPurposeTheLawisT4APIdt dQA==Inthispaper,weshowhowtheStefan–Boltzmann(SB)lawcanbegeneralizedtoanygasoffreeparticles,andwestresstheimportanceofathird ingredientforitsderivation,aSTEFANBOLTZMANN’SRADIATIONLAWAIM:StefanBoltzmann’sradiationLawdescribesthetotalemissionofablackbodyradiatorItstatesthatthetotalradiationTheStefan-Boltzmann(SB)lawrelatestheemissivityq,giveninWm,ofanidealblack-bodycavityatthermal equilibriumtothefourthpoweroftheabsolutetemperatureTasqTheStefan–Boltzmannlaw,alsoknownasStefan'slaw,statesthatthetotalenergyradiatedper unitsurfaceareaofablackbodyinunittime(knownvariouslyastheblackInthispaper,weshowhowtheStefan-Boltzmann(SB)lawcanbegeneralizedtoany gasoffreeparticles,andwestresstheimportanceofathirdingredientforitsderiva-tion,aStefan-Boltzmannlaw,statementthatthetotalradiantheatpower emittedfromasurfaceisproportionaltothefourthpowerofitsabsolutetemperatureWe’veshownthatyoucanuseBose-EinsteinstatisticstoderivePlanck’s radiationlawaswellastheStefan-Boltzmannlaw,whichsaysthattheradiantpoweremittedfromahotTheStefanBoltzmannLawThereisnomoreimportant lawinenvironmentallyrelevantphysicsthantherelationshipbetweenthepowerradiatedbyadensehotbodyandthetemperature:P=eAσT4watts(1)whereT istheabsolutetemperature,Aisthesurfaceareaoftheradiator,andeistheemissivity,afunctionofemittedwavelengthTheStefan–Boltzmannlaw,alsoknown asStefan'slaw,describestheintensityofthethermalradiationemittedbymatterintermsofthatmatter'stemperaturePrincipleItisnamedforJosefStefan,who empiricallyderivedtherelationship,andLudwigBoltzmannwhoderivedthelawtheoreticallyThisisknownasStefan-Boltzmannlaw,whichstatesthat.According ofStefan-Boltzmann’slaw,theenergyemittedbyablackbodyperunitareaandunittimeisproportionaltothepower“four”oftheabsolutetemperatureofthe bodyTheStefan–Boltzmannlaw,alsoknownasStefan'slaw,statesthatthetotalenergyradiatedperunitsurfaceareaofablackbodyinunittime(known variouslyastheblack-bodyirradiance,energyfluxdensity,radiantflux,ortheemissivepower),j*,isdirectlyproportionaltothefourthpoweroftheblackbody's thermodynamictemperatureT(Thenineteenth-centuryIrishphysicistDavidTyndallperformedthefirstcarefulmeasurementsoftheamountofradiationemittedby ablackbodytherateofoutwardradiativeenergy(perunitarea)emittedbyanobjectwithtemperatureTisproportionaltothe4thpowerofTThehigherthe temperatureofanobject,thegreateritsradiativeenergyoutputwillbeTheLawisT4APIdtdQA==rad=εσ,where,εistheemissivityandσistheStefanBoltzmannconstantwhichhasavalueofxW/m2K4HerewediscusstheStefan-Boltzmannlaw.Thelamenttemperatureandpoweroutputofatungstenlampis measuredandcomparedwiththepredictionoftheStephan-BoltzmannLaw:I/TwhereIistheemittedpowerperunitarea,andTisthetemperatureIntroduction TheStefan-BoltzmannconstantTheStefan-BoltzmannLawrelatesthefluxdensity,orthepowerperunitarea,radiatedbyanobjecttoT,theabsolute temperatureoftheobject