Derive the Stefan-Boltzmann formula for the total energy density in blackbody radiation

EV=(π2kB415ħ3C3)T4=7.57×10-16Jm-3K-4T4

Short Answer

Expert verified

Deriving the Stefan-Boltzmann formula for the total energy density in the blackbody radiation is=π21.3807×1023J/K4152.998×108m/S31.5046×10-34J.sT47.566×10-16Jm3K4

Step by step solution

01

Definition of Stefan Boltzmann law

According to the Stefan-Boltzmann equation, the amount of radiation emitted by a dark substance per unit area is exactly proportional to the fourth power of the temperature.

02

Deriving the Stefan-Boltzmann formula for the total energy

From Equation 5.113:

EV=0ρ(ω)dω=hπ2c30ω3(ehω/kBT-1)dω.

Let x=hωkBT.then

EV=hπ2c3kBTh40x3ex-1dx=(kBT)4π2c3h3Γ(4)ς(4)=(kBT)4π2c3h3.6.π490=π2kB415c3h3T4

=π2(1.3807×1023J/K)415(2.998×108m/s)3(1.5046×10-34J.s)3T4\hfill=7.566×10-16Jm3K4T4

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