Question

The mean free path and rms velocity of a nitrogen molecule at a temperature 17C are $1.2\times {10}^{-7}$ m and $5\times {10}^2$ m/s respectively.The time between two successive collisions

• A. $2.4\times {10}^{-10}$ S
• B. $1.2\times {10}^{-10}$ S
• C. $3.4\times {10}^{-13}$ S
• D. $3.4\times {10}^{-10}$ S

Answer 1

The correct option is A $2.4\times {10}^{-10}$ S

Mean free path $\lambda =1.2\times {10}^{-7}$

rms velocity $V_{rms}=5\times {10}^{2}m/s$

Time betweem succesive collisions:

$T=\frac{\lambda }{V_{rms}}$

$=\frac{1.2\times {10}^{-7}}{5\times {10}^2}$

$=0.24\times {10}^{-9}$

$=2.4\times {10}^{-10}s$