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Is the force produce by precession reactionless?

  1. May 6, 2005 #1
    Some studies point so.
    Besides i suposse it´s not against classical physics since nobody important said that spinning forces had reaction
  2. jcsd
  3. May 6, 2005 #2

    Doc Al

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    Do you even know what precession is?
  4. May 6, 2005 #3
    hmm.. could it be that aviator is back?
  5. May 6, 2005 #4


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    I don't doubt that at all... and he still has no clue what "conservation of angular momentum" is.

  6. May 6, 2005 #5
    You are not answering my question, I´m not sure I came to the right place.
    Rotation produces wobbling that produces precession that produces rotation in a different plane than the original rotation.
    I´m better at concepts that at words, but I still find my question easy to answer. Does the force produced by precession have a reaction? If you say that it does not produce a force do you mean that the torque produced by precession is not produced by a force? Then by what is produced the torque induced by precession?
    By the way I´m not an aviator
  7. May 6, 2005 #6


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    Don't know who the original poster is, but I would like to make sure that my own understanding is accurate. Someone please check me on the following response:

    I would have responded that gyroscopic procession is one of the ways in which centrifugal force effects objects. As such, it would not be considered an actuall force, but rather a "pseudo force", just like centrifugal force. Both of these phenomena are simply ways in which inertia manifests itself in an object that has been set spinning by some other, "True" force.

    Would you guys consider that response to be accurate?
    Last edited: May 7, 2005
  8. May 6, 2005 #7
    I dont like to get lost understanding physical forces because of linguistic problems.
    I think the use of concepts like pseudo force makes you lose track of the original concept so I´ll set my question to the minimal physical concept:
    I give torque to the gyroscope, the earth aquires an opposite torque, precession causes a secundary torque in a plane situated 90º from the first plane in the giroscope.Does the earth aquire an oposite torque to this secodary torque of the gyroscope?
    My question can be answered with a simple yes or no
  9. May 6, 2005 #8


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    I don't like the term "pseudo force, but let me explain it anyway: If you are inside a centrifuge, you feel a force pulling you toward the outside of a centrifuge (in a line away from the center). In fact, the force being applied to you is the centrifuge pushing you toward the center.

    The short answer to your first question, however, is that no, there is no such thing as a reactionless force. Any energy loss from a gyroscope being restrained from precession comes from the spinning - ie, it slows down.
    Last edited: May 6, 2005
  10. May 6, 2005 #9


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    I don't really think so. This fellow is far too coherent.

    edit: It's obvious that he's familiar with aviator's questions, though. I just spotted a post about the bicycle wheel/chair example farther down the page.
    Last edited: May 6, 2005
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