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Homework Help: Explanation of Bernouilli's principal of lift?

  1. Jan 8, 2005 #1
    Does anyone have a diagram and/or explination of Bernouilli's principal of lift?
  2. jcsd
  3. Jan 8, 2005 #2


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  4. Jan 8, 2005 #3
    Ummm, maybe somethin g less complicated, i am new to physics and i do not understand all of the lingo yet.
  5. Jan 9, 2005 #4


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    Take a look at the link posted there by pervect. It is from a NASA site.
  6. Jan 9, 2005 #5


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    I STRONGLY advise you to follow Clausius2's suggestion of using pervect's link.
    It's an excellent source.

    Just a hint, though:

    Let us take the simplest case, and just assume that the air always flows smoothly over the wing. (much of the technicality in my thread is to problematize just that assumption)

    Because a wing is typically "downwardly curved", saying that the air always follows the wing is the same as to say that the wing pushes the air downwards. (Think about that..)

    But since then the wing push the air downwards, the air will push the wing upwards, according to Newton's 3.law.
    That is, we have lift!

    This is, I think, the simplest way of visualizing how the lift is achieved;
    note, however, that more detailed arguments is needed to make your ideas rigourous (Jeff Reid&Clausius make several important observations here).

    So, as long as you haven't learnt all the maths yet, I advise you to forget about the "Bernoulli equation".
    Its role in an actual lift situation is rather tricky, many have misunderstood how it should be applied.

    Again, go to pervect's link; it's one of the best non-mathematical sources I've seen which visualize the lift situation.
    Last edited: Jan 9, 2005
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