The conc.of molecules in two ultra-high-vacuum chambers of volumes V1=V2=0.1m^3 is 10^6 molecules/m3(adsbygoogle = window.adsbygoogle || []).push({});

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!

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# Gaussian distribution

Can you offer guidance or do you also need help?

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