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==Explanation==
 
==Explanation==
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{{incomplete|Created by a SPOOKED OUT BOT - Please change this comment when editing this page. Do NOT delete this tag too soon.}}
  
This comic is a parody of the incomplete explanations given to physics students on how wings produce lift. Specifically, it parodies the {{w|equal transit-time fallacy}}, which states that the air flowing above the wing and the air flowing below the wing have to travel from one side of the wing to the other in equal time, so the air above the wing has to travel faster to keep up with the air below. This assumes that the air above the wing is somehow conscious of what the air below the wing is doing. <!-- It also parodies the other two, as mentioned below, but...meh. Someone else can make the narrative flow better. --> This assumption of consciousness is taken to extreme parody by the comic, suggesting that the bottom air can be frightened by skulls, that the top air is curious to see what's going on, and that air can panic. In real life, this is not the case.{{Citation needed}}
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Wings can produce {{w|Lift (force)|lift}}.{{Citation needed}}
  
Wings can produce {{w|Lift (force)|lift}},<ref name="Prandtl & Tietjens (1952)">Tietjens, Oskar Karl Gustav; [https://en.wikipedia.org/wiki/Ludwig_Prandtl Prandtl, Ludwig] (1957). [https://books.google.com/books?id=4KtFcuCZ3VsC&pg=PR1 ''Fundamentals of Hydro- and Aeromechanics'']. Courier Corporation. ISBN 978-0-486-60374-2</ref> i.e. an upwards force with which an aircraft is held in the air. One or more of three main reasons may typically be given as to why airplane wings produce lift:
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Randall previously dealt with explanations of wing lift in [[803: Airfoil]].
* {{w|Bernoulli's principle}} (Perhaps the most frequently cited/demonstrated as a basic introduction to wing-physics.)
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* {{w|Angle of attack}} (The airplane wing angles up so that air is deflected downwards, by the {{w|Newton's sine-square law of air resistance|'ski effect'}}.)
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There are three actual reasons why airplane wings produce lift:
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* {{w|Bernoulli's principle}} (which is the most frequently cited)
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* The airplane wing is angled up at the front so that air hits the bottom and is pushed downwards.
 
* {{w|Coandă effect}} (The top is curved, so air going over the wing must curve downwards in order to avoid creating a vacuum above the back of the wing, and by Newton's third law, this results in an upwards force on the wing.)
 
* {{w|Coandă effect}} (The top is curved, so air going over the wing must curve downwards in order to avoid creating a vacuum above the back of the wing, and by Newton's third law, this results in an upwards force on the wing.)
The comic references all three of these reasons. Airflow splitting references Bernoulli's principle, while the air at the bottom being scared and fleeing downwards is similar to the effect of air hitting the angled bottom of the wing. The air going over the top curving down references the Coandă effect, although the comic claims that this effect is instead caused by the top-air noticing the bottom-air fleeing downward and goes down to investigate why the bottom-air is fleeing. The mention of Newton's third law is indeed correct, even if the movement of the air is for the wrong reasons. In the title text, it additionally suggests that the top-flow also end up glimpsing the printed skulls, causing it to also chaotically flee, generating a wing's classic turbulent wake.
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The comic references all three of these reasons. Airflow splitting references Bernoulli's principle. Air at the bottom being scared down references air hitting the bottom of the wing being angled down. Air at the top curving down references the Coandă effect. Newton's third law references the latter two.
  
[[Randall]] previously dealt with explanations of wing lift in [[803: Airfoil]].
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==Transcript==
 
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{{incomplete transcript|Do NOT delete this tag too soon.}}
<references/>
 
  
==Transcript==
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[Caption at the top of the panel:] How a wing produces lift
:[Caption at the top of the panel above the drawing:]  
 
:How a wing produces lift
 
  
:[The drawing is a diagram of the cross-section of a plane wing. It is large and rounded on the left end and flat on the bottom while the top curves down to meet it at a sharp point to the right. There are many small arrows indicating the flow of wind, in front of, above and below and behind the wing. Four sections of the wind have captions.]
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[A diagram of the cross-section of a plane wing. It is large and rounded on the left end and flat on the bottom while the top curves down to meet it at a sharp point. There are many small arrows indicating the flow of wind, as well as captions.]
  
:[The arrows come from the left of the panel, point towards the wing, and then half begin to go over and half begin to go under. There is a caption in the middle of this flow:]  
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[The arrows come from the left of the panel, point towards the wing, and then half begin to go over and half begin to go under. A caption in the middle of this flow reads:] Airflow splits around the top and bottom of the wing
:Airflow splits around the top and bottom of the wing
 
  
:[The arrow flowing above continue to the back without caption. But the arrows going under the wing goes by a circle underneath the wing. The circle is connected to an arrow which points to the underside of the wing indicating that the content of the circle represents the underside of the wing. The circle shows a repeating pattern of small black (simplified) skulls, that not only fills the circle but can be seen on the arrow pointing to the underside of the wing. There is a caption to the right of this:]  
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[A circle underneath the diagram is connected to an arrow which points to the underside of the wing. A repeating pattern of small black (simplified) skulls fills the circle and arrow. The caption to the right of this is:] Spooky skulls microprinted on the bottom of the wing frighten the air, which flees away downward
:Spooky skulls microprinted on the bottom of the wing frighten the air, which flees away downward
 
  
:[The arrows going above the wing begins to curve downward at the end of the wing. In the middle of these arrows is a caption:]  
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[The arrows begin to curve downwards after this caption, and are joined by the top arrows which have also begun to curve downward. In these arrows is a caption:] Top air goes to see what's wrong
:Top air goes to see what's wrong
 
  
:[After the spooky skulls the arrows under the wings also begins to curve downwards and both streams of arrows from above and below have joined at the end of the wing and are all pointing to the bottom right of the panel. In front of them is a caption:]  
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[Both streams of arrows have joined and are pointing to the bottom right of the panel. In front of them is a caption:] By Newton's third law, downward deflection of air pushes wing upward
:By Newton's third law, downward deflection of air pushes wing upward
 
  
 
{{comic discussion}}
 
{{comic discussion}}

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