# The mean free path is the ________

The mean free path is the average distance covered by a molecule between two successive collisions.

## Mean free path

The mean free path λ of a gas molecule is its average path length between collisions. Mathematically the mean free path can be represented as follows:

$$\begin{array}{l}λ = \frac {1}{\sqrt{2} \pi d^2 \frac NV} \end{array}$$

Where

λ- Average distance travelled by any molecule between collisions

N/V – Number of molecules per unit volume or the density of molecules

d – Diameter of the molecule

### Mean Free Path Factors

Following are the mean free path factors:

• Density
• Number of molecules
• Temperature, pressure, etc