1. Limited time only! Sign up for a free 30min personal tutor trial with Chegg Tutors
    Dismiss Notice
Dismiss Notice
Join Physics Forums Today!
The friendliest, high quality science and math community on the planet! Everyone who loves science is here!

Diffusion Constant

  1. Oct 23, 2013 #1
    1. The problem statement, all variables and given/known data
    Ants are release from the center point of a smooth table and after 1 minute a snapshot is taken and the ants are counted at concentric 5cm circles. There are 10 outer circles ( The most outer circle being 50cm from origin). The number of ants at each ring starting from origin: 3, 5, 15, 19, 37, 23, 11, 1, 0, 0, 2, respectively.

    What are the average displacement, root-mean-squared displacement, and diffusion constant?


    2. Relevant equations
    Average displacement is sum of the squared value of each counted # of ants at each ring,, divided by the number of rings? == [(x1)^2 + (x2)^2 + ... + (xn)^2]/11 ? I'm not sure about this, it seems to easy, and I'm not confident that I understand exactly what is being asked for.

    Root-mean-squared displacement: √[(1/11)*(x1)^2+(x2)^2+ ... + (xn)^2].
    This seems straight forward, but then again, I'm not sure that I started out on the right path.

    Diffusion constant: This is where I'm very lost, I have t = (x^2)/2D but my teacher hinted that the solution was the Gaussian distribution and I have no idea how to derive or arrive at that conclusion. Thanks guys
     
  2. jcsd
Know someone interested in this topic? Share this thread via Reddit, Google+, Twitter, or Facebook

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



Similar Discussions: Diffusion Constant
  1. Gas Diffusion? (Replies: 4)

  2. Molecular diffusivity (Replies: 3)

  3. Diffusion constant (Replies: 1)

  4. Diffusion or osmosis? (Replies: 4)

Loading...