Compton scattering and collision within blackbody

Bailey
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Homework Statement


Consider a blackbody contain atoms that typically produce photons with energy of about 7eV. Estimate the number of photon-electron collision each photon undergoes before it escape the object. Assume the blackbody has a temperature of 1000K.


Homework Equations



λ2 - λ1 = λcompton(1 - cosθ)


The Attempt at a Solution



Not sure if I have all relevant equation but this is what i did:

calculated total kinetic energy by converting the temperature to kinetic energy using Boltzmann constant: kinetic energy=(3/2)KT. Then dived the total kinetic energy by 7eV
 
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Bailey said:
calculated total kinetic energy by converting the temperature to kinetic energy using Boltzmann constant: kinetic energy=(3/2)KT. Then dived the total kinetic energy by 7eV

I don't understand how this helps.

How much energy does a single photon lose in a single Compton scattering? What is the average energy lost over multiple scatterings (with different angles θ)?
 
Both were not given, but I assume 180 degree for max scattering?
 
Bailey said:
Both were not given, but I assume 180 degree for max scattering?

Assuming 180 degree angle is not entirely correct, but you can certainly do it like that, and it will give you at least a good order of magnitude estimate. Ideally you would like to take an average over all possible angles.
 
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