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Homework Help: Fluid problems - pipe like questions

  1. Jan 31, 2010 #1
    Fluid problems - " pipe " like questions

    1. The problem statement, all variables and given/known data
    A fireman climbs a 8 m high ladder carrying a
    5 in diameter hose that has a 1.4 in diameter
    nozzle. The pump has an absolute pressure of
    4 atm.
    What is the water velocity from the nozzle?
    Assume that water is incompressible, its den-
    sity is 1000 kg/m3 , and 1 inch = 0.0254 m.
    The acceleration of gravity is 9.8 m/s2 and 1
    atm = 1.01 × 105 Pa.

    2. Relevant equations
    bernoulli's equation
    volume rate of flow

    3. The attempt at a solution
    ok so first i found the area by converting and doing pie and all that stuff. so after i found A1 and A2, i put A2/A1 which is = to v2/v1 so that means v1 = A2/A1 * v2. with this said its time to plug into bernoulli's equation. P1 + 1/2pv1^2 = P2 + 1/2pv2^2 + pgh.

    P1 = given, just convert atm into Pa
    v1 i plugged into equation
    p = 1000 since its water
    P2 = atmopheric pressure im guessing
    h = 8m

    i plugged everything in but i got it wrong T_T

    i only have 3 other questions besides this one so ill post them as a reply later.
  2. jcsd
  3. Feb 3, 2010 #2


    User Avatar
    Staff Emeritus
    Science Advisor
    Gold Member

    Re: Fluid problems - " pipe " like questions

    Your method appears to be correct. It may be that you made an error in the math along the way. It you post the steps in your calculations, someone might be able to spot the error.
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