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Homework Help: Find the pressure p_1 due to a single particle

  1. Apr 26, 2005 #1
    Please help.

    Find the pressure p_1 due to a single particle. Express the pressure due to a single particle in terms of k_B, T, L_x, L_y, L_z, and any other given quantities.

    I tried using pV=N(k_b)T, but it is wrong.

    Thank you.
     

    Attached Files:

  2. jcsd
  3. Apr 26, 2005 #2
    Care to define those variables?
     
  4. Apr 26, 2005 #3
    k_B is boltzmanns constant. If you look at the picture, you can see that L_x, L_y, and L_z are the length, width and height of the rectangular prism. T is the absolute temperature.
     
  5. Apr 26, 2005 #4
    You can express V in terms of L_x, L_y, L_z
    Is this mastering physics?

    p = kT/V

    No moles here, single particle.
     
  6. Apr 26, 2005 #5
    Yeah, mastering physics. That's what stuffed me up- the moles. Thanks.
     
  7. Apr 26, 2005 #6
    Ok...I've now found the pressure for that, and I also found the pressure fon the wall due to a single particle whose squared speed in the x direction is v_x^2 [the answer to the later is (m*v_x)/V]. Now I need to find the pressure in terms of T, k and V, and any other given quantities, but I can't seem to get it.
     
  8. Apr 26, 2005 #7
    Show me your work for finding the pressure for v_x, and v_x^2.
     
  9. Apr 26, 2005 #8
    p = F/A

    The force is equal to dp(momentum)/dt = (2mv_x)/((2*L_x)/(v_x))

    Area = Ly*Lz

    Therefore, p = (m*v_x)/V
     
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