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Centirpetal And Centrifugal Forces

  1. Jun 25, 2003 #1
    Centripetal and centrifugal forces

    What do you think about the following division, i.e. distinction between centripetal and centrifugal forces?


    Every known force can function as a centripetal force, and has inevitable reaction in centrifugal direction. The terms CENTRIFUGAL AND CENTRIPETAL are only denominations of direction of actioning - toward center or away of it.

    E.G. Astronauts which are orbiting Earth are levitating due to gravifugal force. In a case of levitation of astronauts is erroneus to say: they are levitating due to "centrifugal force" because that term is to general, or to large.

    For more,CLEARER and EASIER to understand, please see at the site:

    Thank you!
    Last edited: Jun 26, 2003
  2. jcsd
  3. Jun 25, 2003 #2
    Good idea, althought i don't really agree with it.
    Scientists try their best to make science 'simpler', with fewer terms, etc ...
    Now, in the case of an astraunot orbitting round earth, the gravitional force on the astraunot works as a centripetal force (for a person watching from an inertial frame of refference), so, the force that the astraunot feels as levitating force is actually a centrifgual force (remember he is not in an inertial frame of refference), so i don't see where the problem comes up.
    You said :
    Can you explain this more, why is it erroneous to say "They are lifted due to centrifugal force, that is due to a centripetal force which is the gravitional force" ?
  4. Jun 25, 2003 #3
    """a case of levitation of astronauts is erroneus to say: they are levitating due to "centrifugal force" because that term is to general, or to large."""

    It is more correct and more precize and clearer to say "gravifugal force", because it is the reaction to the gravipetal force action.

    If we rotate the little stone on the string, we also deal with centrifugal and centripetal force (speaking generaly), but it is much better to say: cohesipetal and cohesifugal or solidopetal and solidofugal force.

    There are some esential differences between the two pair of force

    Gravipetal - gravifugal
    Cohesipetal - cohesifugal

    Equation for the first pair - grav.:
    GMm/R2 - mv2/R
    Equation for the second pair - cohesi.:
    mv2/r - mv2/r

    Behaviour of the rotating mass and forces is also quite different.
    Please see details at:
    Thank you
    Last edited: Jun 25, 2003
  5. Jun 25, 2003 #4


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    No... you still misunderstand the idea of centripetal effects. What happens is best seen as falling but missing the ground. The object in orbit is continuously falling under the unbalanced force of attraction, but constantly missing the ground.

    Have you done calculus?
  6. Jun 26, 2003 #5
    Dear sir,
    your opinion is not incorrect, but it is only simplicication for schoool-children.
  7. Jun 26, 2003 #6


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    That is why I asked if you know calculus. I can give you the full complex version if you desire.

    And you didn't say why the model isn't correct.
  8. Jun 27, 2003 #7
    OK, OK
    You are right
  9. Jul 3, 2003 #8
    But there is no centrifugal force.......
  10. Jul 4, 2003 #9
    I do not understand what are you talking about, but you are right.
    Last edited: Jul 5, 2003
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