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Homework Help: Conceptual question about currents and pumps

  1. Mar 18, 2007 #1
    1. The problem statement, all variables and given/known data

    3zk5tvd.jpg


    2. Relevant equations

    I suppose the energy density equation applies here:

    (P2-P1) + pg(y2-y1) + 1/2p(v2^2 - v1^2) = Epump/vol - IR

    and

    I = Av

    3. The attempt at a solution

    My initial thought was that the current is the same. But then, since current is Av, I was second guessing myself that maybe the velocities are different. Any help's appreciated!
     
  2. jcsd
  3. Mar 18, 2007 #2
    Also, I'd appreciate it if you guys can help me on these

    2uf7jwi.jpg

    My guess was that the sewer gas is less than 1 ATM.

    3y80nb5.jpg

    My guess is that the pressures are the same. Using the same energy density equation on the first post, I could eliminate the KE, Epump, and IR. That leaves the pressure and the PE. Since it's measuring the same height, the pressure's the same. Is this correct?
     
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