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Gaussian distribution

  1. Sep 21, 2010 #1
    The conc.of molecules in two ultra-high-vacuum chambers of volumes V1=V2=0.1m^3 is 10^6 molecules/m3

    You count the # of molecules N1 and N2, in each chamber at some moment of time.

    a.find the expectation value and the SD of N1 and N2 . calc [tex]\sigma[/tex][tex]_{N1}[/tex], sketch the prob distribution of N1.


    I used SD= sqt(pq) x sqt(N)

    =sqt(0.5x0.5) x sqt (2,000,000)
    =707.1

    I assume for Expectation value i use

    W= [tex]\underline{N!}[/tex](v/V) (1-v/V)[tex]^{N-n}[/tex]
    n!(N-n)!

    I am just sure if N will be 2million, or even what my n will be...

    any help be appriciated!
     
  2. jcsd
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