Finding the mean free path using the given values?

AI Thread Summary
The discussion focuses on calculating the mean free path of electrons given their concentration and temperature. The relevant equations for the mean free path are provided, but key values such as the diameter (d) and pressure are missing, complicating the calculations. There is uncertainty about whether to assume standard atmospheric pressure for the calculations. The user discovers that conductivity can be used alongside mobility and relaxation time to derive the mean free path. Ultimately, the discussion emphasizes the importance of identifying all necessary parameters for accurate calculations.
joemmonster
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Homework Statement



The concentration of electrons per unit volume is given (atoms/m^3), temperature is also given in Kelvins (100 K). Other values were also given such as valence but I'm pretty sure that they are irrelevant.

Homework Equations


λ = 1/ pi * d^2 * n
λ=kT/4∗π∗√2∗r^2*p

The Attempt at a Solution


n is given but I can't find other relevant values to be inserted in the equation since d is missing and the problem didn't provide it. On the second equation, pressure is missing but I don't know if I can assume that the pressure is 1 atm.
 
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joemmonster said:

Homework Statement



The concentration of electrons per unit volume is given (atoms/m^3), temperature is also given in Kelvins (100 K). Other values were also given such as valence but I'm pretty sure that they are irrelevant.

Homework Equations


λ = 1/ pi * d^2 * n
λ=kT/4∗π∗√2∗r^2*p

The Attempt at a Solution


n is given but I can't find other relevant values to be inserted in the equation since d is missing and the problem didn't provide it. On the second equation, pressure is missing but I don't know if I can assume that the pressure is 1 atm.
I assume we are dealing with some random distribution in space of identical bodies, and you want the mean distance one could travel in a straight line without striking another. What parameters do you think will matter?
 
Ok, I just found out that conductivity is also given which I can finally derive mean free path by using mobility and relaxation time.
 

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