Dismiss Notice
Join Physics Forums Today!
The friendliest, high quality science and math community on the planet! Everyone who loves science is here!

Homework Help: Fluid mechanics - u tube manometer

  1. Mar 13, 2010 #1
    dont have a picture to show,

    a solution is pumped through a pipe with an obstacle in it, to find the difference in the pressure on either side of the obstacle, a u tube manometer with mercury is fitted to it and a height difference of 19cm is measured. what is the pressure after the obstacle if the solution is pumped in at pressure P1?

    given

    Δh=0.19m
    ρsolution=1070kg/m3
    ρmercury=13520kg/m3

    now in my lecture notes i have 2 equations, one being
    ΔP=g*Δρ*Δh
    and the other being
    ΔP=g*ρmercury*Δh

    so P2=ΔP+P1 (P2<P1)

    which one do i need to use, since ρsolution<<ρmercury i get similar results but which is correct?
     
  2. jcsd
Share this great discussion with others via Reddit, Google+, Twitter, or Facebook

Can you offer guidance or do you also need help?
Draft saved Draft deleted