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Fluid dynamics

  1. Jan 26, 2006 #1
    The velocity of the water that comes out of the opening in the attached diagram can be found using Bernoulli equation, as

    v = sqrt (2gh)

    Once the water exits the hole, I am not sure how to answer questions like the following: Can I use conservation of energy and momentum. Also can I use the equations in kinematics (ie. S = ut + 1/2 a t^2, v=u+at,...)

    1. Time for the water to hit the ground,
    2. What is the value of H
    3. What is the horizontal distance of flight of water
    4. What is the acceleration ( acce. of gravity??)

    Thanks a lot.


    Attached Files:

    Last edited: Jan 26, 2006
  2. jcsd
  3. Jan 26, 2006 #2
    Usually the kinematic equations are all you need assuming you know the initial geometry of the set up. I see no picture, so I can't tell.
  4. Jan 26, 2006 #3
    Yes the pic did not show up. It is there now. Sorry.
  5. Jan 26, 2006 #4
    How about conservation of energy and momentum? I can cosider a mass of water that exits the hole per unit time as 'm' and write the conservation lows. Is seems ok to do that.

    edit: May be momentum is not conserved in the vertical direction due to the force of gravity.?
    Last edited: Jan 26, 2006
  6. Jan 26, 2006 #5
    You could use conservation laws also, I presume
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