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Gauge Pressure of garden hose

  1. May 17, 2006 #1
    [SOLVED] Gauge Pressure

    A garden hose is attached to a water faucet on one end and a spray nozzle on the other end. The water faucet is turned on, but the nozzle is turned off so that no water flows through the hose. The hose lies horizontally on the ground, and a stream of water sprays vertically out of a small leak to a height of 0.68 m. What is the gauge pressure inside the hose? (Gauge pressure is the amount by which the pressure exceeds atmospheric pressure.)

    how would I find this??
  2. jcsd
  3. May 17, 2006 #2

    Andrew Mason

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    What is its kinetic energy per unit mass when the water is leaving the hose if it rises .68 m? What is the relationship between pressure difference and velocity of a fluid passing from a region of low (no) speed to higher speed? (Look up Bernouilli's equation).

  4. May 17, 2006 #3
    P + (1/2)pv^2 + pgh
    p=density of air=1.29 kg/m^3
    how do I find P and velocity?
  5. May 17, 2006 #4
    p=denisty of water = 1.00*10^3 kg/m^3
  6. May 17, 2006 #5
    nevermind, i got it P=pgh + Patm
  7. May 18, 2006 #6
    No, you didn't (I mean not fully). Just read how you defined gauge pressure.
  8. Sep 14, 2007 #7
    I have to do this question too.

    How do I find the velocity w/o knowing the time?
  9. Sep 14, 2007 #8


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    If one knows or calculates the kinetic energy or mass flow rate (and density and cross-sectional area) or volumetric flowrate and cross-sectional area, the velocity can be calculated.

    Or experimentally, use an anemometer (either UT or laser)
    Last edited: Sep 14, 2007
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