Mean Free Path and RMS Speed
Mean Free Path and RMS Speed: Overview
This topic consists of various concepts like Time for Successive Collisions between Walls,Mean Free Path,, etc.
Important Questions on Mean Free Path and RMS Speed
The mean free path of molecules of a certain gas at STP is , where is the diameter of the gas molecules. While maintaining the standard pressure, the mean free path of the molecules at is approximately:

Why do gases conduct electricity at low pressure?

An ideal gas is enclosed in a cylinder at pressure and temperature. The mean time between two successive collisions is . If the pressure is doubled and temperature is made one fourth, determine the time between two successive collisions in .

The collision frequency of nitrogen molecule in a cylinder containing at pressure and temperature is approximately: (Take radius of a nitrogen molecule is )

Give the mathematical expression for the time of successive collisions between the walls of the container with.

Time for successive collisions between walls :-
(ii) Time for two successive collision between the walls is.

Time for successive collisions between walls ;-
(i) When there is collision between two walls then charge in momentum per second is .

Derive the formula for time for successive collision between the walls of the container with the molecule.

The mean free path and RMS velocity of a nitrogen molecule at a temperature are and , respectively. The mean time between two successive collisions will be , what is the value of .

The mean free path of a gas sample is given by:

If the temperature and pressure of a gas is doubled the mean free path of the gas molecules

Calculate the time taken between two successive collisions for a helium molecule having a diameter and an average velocity of , consider molecules present per unit volume.

For a molecule of an ideal gas, the number density is and the mean free path is . The diameter of the gas molecule is

Consider an ideal gas confined in an isolated closed chamber. As the gas undergoes an adiabatic expansion, the average time of collision between molecules increases as , where is the volume of the gas. The value of is :-

Define the following
Mean free path

Define the following
Free path

A container is divided into two equal part I and II by a partition with small hole of diameter d. The two partitions are filled with same ideal gas, but held at temperature and by connecting to heat reservoirs. Let and be the mean free paths of the gas particles in the two parts such that and Then is close to.

At any instant, the position and velocity vectors of two particles are respectively. They will collide if :

In the following a statement of Assertion is followed by a statement of Reason.
Assertion: Mean free path of a gas molecule is inversely proportional to the density of gas.
Reason: Path of a gas molecule between two adjacent collision is straight line.

Consider an ideal gas confined in an isolated closed chamber. As the gas undergoes an adiabatic expansion, the average time of collision between molecules increases as , where is the volume of the gas. The value of is
