Question goes as follows:(adsbygoogle = window.adsbygoogle || []).push({});

"In an ionised gas there are positive ions and electrones moving around in collision with molecules of the gas. Calculate the ratio of the mean free path of the electrons in the gas to the mean free path of the positive ions in the gas."

As far as I can see I only need

lamda = (KT)/(4pi root2 r^2 p)

where everything will cancel except r giving r1:r2 ratio

I could assume r is roughly 1x10^-10 for the molecules, but I don't think I'm supposed to know or find r for the electron since the compton radius ( (e^2/(me c^2) ) is a little beyond what we've done.

What have i missed..?

- Rob

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# Homework Help: Mean Free Paths

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