- #1
albega
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Homework Statement
What is the mean free path of an N2 molecule in an ultra-high-vacuum chamber at a pressure of 10-10mbar?
Homework Equations
λ=1/(√2)nσ
number density n, collision cross-section σ
p=nkT
pressure p, temperature T
σ=πd2
d molecular diameter
The Attempt at a Solution
λ=kT/(√2)πpd2
where we know p and I can estimate d to be around 10-10m. However I am not given T, and I don't really see how I could know what it is...