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Summary
DescriptionCrossSectionFig1.svg
English: In a gas of particles of individual diameter $2r$, the cross section $\sigma$ for collisions is related to the particle number density $n$, and mean free path between collisions $\lambda$.
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=={{int:filedesc}}== {{Information |description={{en|1=In a gas of particles of individual diameter $2r$, the cross section $\sigma$ for collisions is related to the particle number density $n$, and mean free path between collisions $\lambda$.}} |date=...