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The next thing you'll be telling us is that space curves around dense
objects, window glass doesn't flow (see
<http://www.cmog.org/index.asp?pageId=745>), and the color of the sky is
determined by more than Rayleigh's law but is also dependent on
non-molecular particles and particle volumetric density (see Sky in a Bottle
by Pesic). :-)
It seems like this corrective movement about flight and Bernoulli has
surfaced in recent years. How did it get started? NASA?
Well, here's one source <http://amasci.com/wing/airfoil.html>
Natasha Aristov wrote:
> ISEN-ASTC-L is a service of the Association of Science-Technology Centers
> Incorporated, a worldwide network of science museums and related
> institutions.
> *****************************************************************************
>
>
> Uh-Oh.
>
> Bernouilli's principle states, or rather observes, that the pressure in
> a moving fluid is lower than the pressure in a standing fluid. This is
> hard to believe at first glance, but I use the analogy of cars on a
> freeway: when they are moving fast, the distance between them is larger
> (low pressure), when they are in a traffic jam, the "car-fluid pressure"
> is high.
>
> So much to Bernouilli.
>
> The only ONLY way to get anything to fly is by making the air pressure
> below the object higher than the air pressure above the object. It has
> nothing to do with wing SHAPE -- the wing shape can help make flying
> more efficient, but it is not decisive in whether a thing will fly.
> Check out some pieces of trash one day on a windy day.
>
> So: you set up a pressure differential above and below a plane wing.
> You do this by moving the plane through the air at very high speeds so
> that the air gets shoved up under the forward part of the wing. The
> wing blocks (part of) the air from flowing behind it: So you have high
> pressure below and low pressure behind.
>
>
> SO.... it turns out (it is a CONSEQUENCE, not a cause!!!) that the air
> particles below the wing are slower than the air particles above the wing.
>
>
> Still don't believe this?: a terrible, common "explanation" of flight
> is that because the wing is shaped the way it is, the air above the wing
> has a longer distance to travel than the air below the wing. So it
> moves faster to keep up.
>
> WHAT???? How does air know how far it has to go? And ... why does it
> need to keep up with the other air????
>
> Bernouilli is OK, but it doesn't make planes fly. Flying planes make
> Bernouilli.
>
>
>
> But what do I know? I'm just a chemist.
>
> Natasha
>
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Wayne T. Watson (Watson Adventures, Prop., Nevada City, CA)
(121.015 Deg. W, 39.262 Deg. N) GMT-8 hr std. time)
Obz Site: 39° 15' 7" N, 121° 2' 32" W, 2700 feet
--
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