Kinetic Gas Theory

1. Nov 19, 2009

prose100

To Anyone,

Note: This is not homework. These are questions that I have come up with during independent study at my job.

Question 1:

The mean speed for escaping molecules from a hole is 1.88*(k*T)/m)^1/2 (Eq.1)

The mean speed for molecules in the Maxwell-Boltz Distribution is 1.596*((k*T)/m)^1/2 (Eq.2

If you were to calculate molecular flux for an ideal gas, which expression would you use?
In my textbook, it uses Eq.2 This does not make sense to me. I would use Eq.1

Question 2:

How does I*dv = 1/4*v*n*dv (Eq.3), using I=1/4*n*vmean (Eq.4)?

Eq.3 represents molecular flux, I (that strike a surface, per unit area and per unit time) with molecular speeds in the range v+dv

Eq.4 represents molecular flux, I

I understand the derivation for Eq.4
I do not understand how can you use Eq.4, which has vmean, to get to Eq.3, which has v?

Any help would be appreciated!