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Velocity of gas

  1. Sep 29, 2009 #1
    1. The problem statement, all variables and given/known data
    Calculate Velocity of an oxygen molecule at height, where the temperature is -50C.
    O2 molecule: 5.4x10^-26 kg


    2. Relevant equations
    1/2mC^2=3/2kT


    3. The attempt at a solution
    => 1/2 (5.4x10^-26) c^2 = 3/2 (1.38x10^-23) x -(50)
    => c2= 1.035x10^-21
    =>c=3.21x10^-11 m/s

    ermmi have a feeling that i messed somewhere lol.
     
  2. jcsd
  3. Sep 29, 2009 #2

    Redbelly98

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    Try that step again. Also, note that you get a negative value for c2, another clue that something is wrong.
     
  4. Sep 29, 2009 #3
    OOhh.. i thought iT being a big negative value would be wrong..
    is this what i did wrong
    -1.035x10^-21/2.7x10^-26=-38.3x10^3m/s
    but it cant be square root =? as its negative
     
    Last edited: Sep 29, 2009
  5. Sep 29, 2009 #4

    Redbelly98

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    That's a little better, but yes that negative is still a problem.

    If I told you not to use -50 for the temperature, even though the temperature is -50 C, does that help?
     
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