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Homework Help: Momentum and continuity equation

  1. Aug 16, 2012 #1
    1. The problem statement, all variables and given/known data

    Follow the link to see the question,

    http://img507.imageshack.us/img507/2246/fluidquestion.png [Broken]

    2. Relevant equations

    3. The attempt at a solution

    currently I can't do part a) but from using part a) I can obtain the forces acting on the cone by using the first part of the equation (ρQ^2/2*A2) and then the force acting on the nozzle by using all of the equation,

    for part a) I currently have used the continuity equation to work out what v1 and v2

    v1= 0.764 m/s and v2= 8.475 m/s

    then I am stuck as what to do with bernoulli's equation if that is the correct next step?
    Last edited by a moderator: May 6, 2017
  2. jcsd
  3. Aug 16, 2012 #2


    User Avatar

    Staff: Mentor

    Is this question from a take-home exam?
    Last edited by a moderator: May 6, 2017
  4. Aug 16, 2012 #3
    no, They are old exam questions to help us revise.
  5. Aug 18, 2012 #4

    You have 3 equations to work with.

    1. Continuity equation relates velocities to flow Q.
    2. Bernoulli's equation relates velocities to pressure.
    3. Momentum equation relates velocities to pressure force and bolt force.

    Use all three and you will get the posted answer.
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