일반물리학 1 — The Kinetic Theory of Gases: Problem 51

51 The atmospheric density at an altitude of 2500 km is about $1 \text{ molecule/cm}^3$. (a) Assuming the molecular diameter of $2.0 \times 10^{-8} \text{ cm}$, find the mean free path predicted by Eq. 19-25. (b) Explain whether the predicted value is meaningful.