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Homework Help: Maxwell speed distribution

  1. May 16, 2012 #1
    halo, I´m stuck in an definite integral...

    P(v)=4π (M2πRT)3/2⋅v2⋅e−Mv2nRT (maxwell speed distribution)

    How can I calculate the fraction of Ar in mars?

    pd. I got already the scape velocity

    But... How can I intregrate and evaluate between (0, 5XE3 m/s) or (5XE3 m/s, infinite) ??

    Is there any tables for evaluate this??

  2. jcsd
  3. May 17, 2012 #2
    You can at least find tabulated values for the error function, erf(x) = 0x dx' exp(-x'^2). It might be easier just to plug in the numbers and integrate numerically, for example by using wolfram alpha.
  4. May 17, 2012 #3
    I calculated in Origin 8.5 (five minutes) trapezoids area... 50 000 intervals... It work as well and "rough" solution, good for giving a fast solution.
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