QJEEM20Ph99c5: JEE Main 2020 Physics - Class 11 JEEM20Ph99c5 Solution: An ideal gas in a closed container is slowly heated. As its…

The mean free path of molecules of an ideal gas is given as:

$$\lambda$$ = $$\frac{V}{\sqrt{2}\pi d^{2}N}$$

where : V = Volume of container
N = No of molecules

Mean free path is independent of temperature hence with increasing temp since volume of container does not change (closed container), so mean free path is unchanged.

Average collision time =

$$\lambda$$

V_av

and V_av $$\propto$$ $$\sqrt{T}$$

$$\therefore$$ Average collision time $$\propto$$ $$\frac{1}{\sqrt{T}}$$

Hence with increase in temperature the average collision time decreases.