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Subject:
From:
Wayne Watson <[log in to unmask]>
Reply To:
Informal Science Education Network <[log in to unmask]>
Date:
Sat, 2 Dec 2006 09:30:25 -0800
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ISEN-ASTC-L is a service of the Association of Science-Technology Centers
Incorporated, a worldwide network of science museums and related institutions.
*****************************************************************************

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
> 
> ***********************************************************************
> More information about the Informal Science Education Network and the
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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
-- 
           "I have made this letter [e-mail] a rather long one, only
            because I didn't have the lesiure to make it shorter."
                                 -- Blaise Pascal
                     Web Page: <home.earthlink.net/~mtnviews>

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