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Pressure of fluid

  1. Jun 24, 2012 #1
    According to Bernoulli eq Pressure of a fluid in a vertical pipe is lower where area is small.But from General formula P=F/A.Pressure should be higher.Isnt it a contradiction?
  2. jcsd
  3. Jun 24, 2012 #2
    Some fluids have minimal compression, like water. Two vertical pipes joined at the bottom with one smaller than the other would have movement.
  4. Jun 24, 2012 #3
    Sorry I didnt get the point.Im assuming an incompressible fluid.
  5. Jun 24, 2012 #4
  6. Jun 24, 2012 #5


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    It would be if F were a constant. In Bernoulli's equation it is the fluid flow that is constant, not the force
  7. Jun 24, 2012 #6
    Why F is not constant?On which factors does F depends here?
  8. Jun 25, 2012 #7
    Is this explanation correct?
    There are two types of pressures :
    1)Static pressure
    2)Dynamic pressure
    In bernoullis eq we are talking about Dynamic pressure which increases or decreases wd fluid speed.
  9. Jun 25, 2012 #8
    With minimal compression, the fluid doesn't follow PV=P1V1. If you have flow from a small section to large the pressure is lower, if its a compressible fluid that gets changed to velocity F=mv2, if its not velocity slows down.

    I think
  10. Jun 25, 2012 #9
    I didnt get my answer.:(
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