MCQ
If $\mathrm{n}$ is the number density and $\mathrm{d}$ is the diameter of the molecule, then the average distance covered by a molecule between two successive collisions (i.e. mean free path) is represented by :
  • A
    $\frac{1}{\sqrt{2 n \pi d^2}}$
  • B
    $\sqrt{2} \mathrm{n} \pi \mathrm{d}^2$
  • $\frac{1}{\sqrt{2} \mathrm{n} \pi \mathrm{d}^2}$
  • D
     $\frac{1}{\sqrt{2} n^2 \pi^2 d^2}$

Answer

Correct option: C.
$\frac{1}{\sqrt{2} \mathrm{n} \pi \mathrm{d}^2}$
c
$\mathrm{n}=$ number of molecule per unit volume

$\mathrm{d}=$ diameter of the molecule

$\lambda=\frac{1}{\sqrt{2} \pi \mathrm{d}^2 \mathrm{n}}$     (By Theory)

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