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Can anyone help?

  1. Sep 14, 2007 #1
    Hi, I have a query with an example as I wish to discover if this has a specific name within physics.

    A sealed jar is half filled with a viscous liquid. I then shake the jar continuously with the liquid impacting against the lid.

    Is this merely momentum? energy transfer perhaps?
    All suggestions/answers are appreciated.

    RikkoSuperb
     
  2. jcsd
  3. Sep 14, 2007 #2
    Oil sloshing about a jar? What's the specific phenomenon that's being considered here?
     
  4. Sep 14, 2007 #3
    I am not sure what the question is.
     
  5. Sep 15, 2007 #4
    The liquid uses the motion to exert a force/pressure on the lid. What can this action be described as?
     
  6. Sep 15, 2007 #5
    Newton's third law.
     
  7. Sep 15, 2007 #6
    I once proposed a similar situation, and was shown to use both conservation of energy and momentum to determine whether the maximum miscibility (e. g., energy and momentum transfer) occurred when the jar was half full.

    My guess proved correct.
     
  8. Sep 15, 2007 #7

    symbolipoint

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    From the viewpoint of someone who is not a rheologist and not a physicist:

    You are mixing air with liquid; is it turbulance? Low surface tension in relation to the force placed on the liquid? Does the situation have a name?
     
  9. Sep 15, 2007 #8
     
  10. Sep 16, 2007 #9
    good point, i am not a physics master but would any turbulence be created? If it where and on this scale, surely it would be minimal.
     
  11. Sep 16, 2007 #10
    tom1661, you said,

    "Besides, all physics is relativistic, and conservation of the total energy and momentum always requires the energy and the momentum of an observed part of a system to in- or de-crease as: E = SQR(m2c4+c2p2)
    In fact all added energy of the liquid is kinetic, i.e. the particles get higher velocities with respect to the shaking observer, but also with respect to the particles of the liquid. The last, due to increased angular momentum of the particles and increased relative momentum between the liquid particles themselves."

    Would the energy transfered from the observer be magnified by the liquid once it has impacted with the lid? Sorry if this seems a dumb questions but I am more of a programming expert than a physicist. Thanks for the interesting discussion so far guys :)
     
  12. Sep 16, 2007 #11
    tom1661 said,

    "Besides, all physics is relativistic, and conservation of the total energy and momentum always requires the energy and the momentum of an observed part of a system to in- or de-crease as: E = SQR(m2c4+c2p2)
    In fact all added energy of the liquid is kinetic, i.e. the particles get higher velocities with respect to the shaking observer, but also with respect to the particles of the liquid. The last, due to increased angular momentum of the particles and increased relative momentum between the liquid particles themselves."

    would the energy transfered from the observer be magnified by the liquid thereby increasing the impact on collision with the lid? sorry if this is silly but i am a programmer and not a physicist.
     
  13. Sep 16, 2007 #12
    All liquid molecules together collide as a liquid. As a result of the shaking of the jar the wavelike character will become turbulent. But this is just a way in which the added energy due to the shaking of the jar is observed. There is no magnification of the energy due to the liquid. Energy cannot be created out of nothing. Most physical processes describe nothing else than energy transfer between observed bodies. This is called work. A little part of the energy transferred to the liquid during collision with the shelf is transferred into sound waves through which you hear the liquid colliding with the jar. So not all energy used to shake the jar will be transferred to the liquid, but almost all will be transferred.

    Greetings Tom.
     
  14. Sep 16, 2007 #13
    It sounds like a milk shake

    --------------------

    oh and if it were eggs, it would eventually be an omelette
     
    Last edited: Sep 16, 2007
  15. Sep 17, 2007 #14
    many thanks tom1661
     
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