(adsbygoogle = window.adsbygoogle || []).push({}); 1. The problem statement, all variables and given/known data

The Cosmic microwave background radiation fits the Planck equations for a blackbody at 2.7 K. a) What is the wavelength at the maximum intensity of the spectrum of the background radiation ? b) What is the frequency of the radiation at the maximum? c) what is the total power incident on Earth from the background radiation

2. Relevant equations

lambda(max)*T=2.898*10^-3 m*K

T=2.7 K

f=c/lambda(max)

sigma=5.6703e-8 W/m^2*K^4

R=sigma*T^4 or

3. The attempt at a solution

a) lambda(max)= 2.898*10^-3 m*K/(2.7 K)=1.0733*10^-3 m

b)f=c/lambda=(3e8 m/s)/(1.0733*10^-3 m)= 2.795 *10^11 /s

c)R =sigma*T^4= (5.6703e-8 W/m^2*K^4)((2.7 K)^4=3.013e-6

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# Homework Help: Blackbody radiation frequency problem

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