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Thermodynamics u-tube help

  1. Jan 25, 2007 #1
    Consider a U-tube whose arms are open to the atmosphere. Now water is poured into the U-tube from one arm, and light oil (p=790 kg/m^3) from the other. One arm contains 70 cm high water, while the other arm contains both fluids with an oil-to-water height ratio fo 4. Determine the height of each fluid in that arm.

    any help an explanation would be greatly appreciated
  2. jcsd
  3. Feb 22, 2007 #2
    Ok simple, we know that the pressure exerted by a fluid is explained by the following relation: P= rho * g * height of water. g is the gravity. now on the water side we have P = Rho of water*g*H on the other side we have
    P= Rho water*g*H1 + Rho Oil*g*4H1 (since height of oil is 4 times that of water). since we are in equilibrium then the pressures will be equal. P1=P2. g cancels from both equations, and the rest are known values leaving us with H1 to figure out.Easy ?
  4. Feb 22, 2007 #3
    btw this is not even close to thermodynamics !!
  5. Feb 23, 2007 #4


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