Dismiss Notice
Join Physics Forums Today!
The friendliest, high quality science and math community on the planet! Everyone who loves science is here!

Kinetic Gas Theory

  1. Nov 19, 2009 #1
    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!
  2. jcsd
Share this great discussion with others via Reddit, Google+, Twitter, or Facebook

Can you offer guidance or do you also need help?
Draft saved Draft deleted