Talk:List of common misconceptions/Archive 3

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Page of Random Trivia

While mildly interesting to read, isn't this just a page of random trivia? There's no observable theme throughout the article, other than being a list of 'commonly' held misconceptions. If all such misconceptions were listed, the page would be virtually endless, and I also have serious doubts that anyone can truly verify what is a 'commmonly' held misconception. At the very least, I suspect this page will be a Western-centric list of trivia that certain editors find interesting, rather than a page of any encyclopaedic value. Blaise Joshua (talk) 12:49, 25 February 2008 (UTC)

Talking of which, why are so many entries unsourced? Unless something is done to correct this, this really is Wikipedia at its worst and most unrealiable. Although I would question the validity of this article existing in any form, surely while it is up every single 'fact' should be sourced. Otherwise it's just a collection of unverified trivia. This page really does need attention. Could we please enter into some kind of discussion regarding these points. Blaise Joshua (talk) 09:39, 27 February 2008 (UTC)

Why has the above not been addressed, in particular the fact that many entries are unsourced? Is it in the hope that this will sneak under the radar and that we all know such unsourced trivia shouldn't be on Wikipedia? I'm sure that's not the case, but this needs to be addressed and sorted out. Any entries that cannot be reliably cited should be removed. Blaise Joshua (talk) 08:27, 4 March 2008 (UTC)

Then remove it. No sense in repeatedly posting that unsourced information needs removed. If it needs to be, remove it. ~QuasiAbstract (talk/contrib) 12:34, 4 March 2008 (UTC)

i'll take sometime later in the week to ind citations for those without -Ishmaelblues —Preceding unsigned comment added by Ishmaelblues (talk • contribs) 18:03, 4 March 2008 (UTC)

I was giving people a chance to respond and, more importantly, to reference material that they've added. I'm not one for unilateral action : o ) 86.45.193.55 (talk) 12:56, 5 March 2008 (UTC)

I had noticed that you had been posting these for about a week, plenty of time for people to at least say they're going to look for cites. In any case, a {{fact}} tag could have been placed on each of the items that need to be cited. Seems to me that if after over a week of posting without response, it's no longer a unilateral decision, as people have made their choice by not responding...but that's just me. ~QuasiAbstract (talk/contrib) 13:03, 5 March 2008 (UTC)

I'm leaving gaps between deleting unsourced material. For those that are putting them back in (two, I think), saying that's it's easy to source, could you please just go ahead and source them. I don't know where the sources for these things are - if you're saying that you do know where they are and they're easy to find, then it's nice and easy for you to do them. As for the sources being in links, surely that's not good enough. Why should any casual reading of Wikipedia have to go searching for verification that what they read is true? It should be sourced right there! Blaise Joshua (talk) 17:18, 17 March 2008 (UTC)

I replaced the thing about the moon's phases not being caused by the shadow of the Earth. That is such common knowledge that I'm not even sure it needs to be sourced. Even so, some children's science books get this wrong, so I think it's appropriate to include it. If you're looking for sources, you could check out the Moon article. Rracecarr (talk) 18:04, 17 March 2008 (UTC)

I've no problem with points being replaced, but what you say doesn't really make any sense. If it's such common knowledge, why is it on a page about common misconceptions? For persons like me who have very little scientific knowledge, these items need to be sourced, and should really be sourced by the people that include them in the first place or people that no about the subject. 23:12, 17 March 2008 (UTC) —Preceding unsigned comment added by Blaise Joshua (talk • contribs)

Factual error in physics

It says: "Bicycles and motorcycles don't use gyroscopic forces to balance.[23][24][25]. The stability of a bicycle is a result of its geometry and the rider's ability to counteract tilting by steering."

I do not know of other definitions of gyroscopes or other alluded false beliefs , but bikes DO use the angular momentum of their massive spinning wheels in order to maintain the Vector's position in space. The same basic principle applies to gyroscopes. The sources cited were probably misunderstood. -01:50, 17 March 2008 (UTC)~

I changed the wording (note that I didn't put the entry into the article). The angular momentum is not necessary for a rider to balance a bike. However, a bike pushed fairly fast on a smooth surface will balance itself, and that stability does depend in part on precession. Rracecarr (talk) 02:17, 17 March 2008 (UTC)

Recent changes

I have commented out (again) the thing about space not being cold. Anything you put in interstellar space will cool to the temperature of the microwave background radiation, 3.2 K or so. That's cold. If the point is that "space" by definition is empty, so doesn't have a temperature, that's more a semantics/definition thing than a misconception about astronomy. Also, the entry had half a dozen typos.

BJ has eliminated the entry about reading in low light not causing bad vision. That can be cited. It would be better to add a {{fact}} tag than simply to delete. Rracecarr (talk) 18:26, 20 March 2008 (UTC)

guidelines for "common misconceptions"

With any other article, I would normally agree with Blaise Joshua -- if it can't be verified, it doesn't belong in Wikipedia. However, I feel this article is different enough from normal articles that I would prefer a slightly different guidelines for this list of common misconceptions: --68.0.124.33 (talk) 04:34, 25 March 2008 (UTC) :

• Each misconception has one link -- to a Wikipedia article about that subject that describes the misconception. (If that article is long, a direct link to the specific section that describes the misconception).
• That Wikipedia article about that subject describes the misconception in context, and holds all the scholarly references to verify (Wikipedia:Verifiability) that it is a misconception.
• For this one "common misconceptions" article, a link to some other Wikipedia article is the only reference necessary for each misconception -- unlike normal articles, where Wikipedia is not an acceptable reference (Wikipedia:Reliable_source_examples#Are_wikis_reliable_sources?).

Benefits of these guidelines:

• Eliminate controversy over whether something is or is not "encyclopedic enough" to warrant a place on this page. If some other Wikipedia article mentions that something is "a common misconception", it is encyclopedic enough for this page -- and if it's not encyclopedic enough to make it into that other article, it's not encyclopedic enough for this page, either.
• Eliminate controversy over whether something is a misconception or is actually true, or at least a valid alternative viewpoint. If some other Wikipedia article says that something is "a common misconception", that's close enough for this page. And if that other Wikipedia article can't get consensus that something is really a misconception (possibly because it can't get any references), then it doesn't belong here on "common misconceptions".
• Makes it much easier to fix inconsistencies where this page says one thing, and the article about the subject says the opposite. First careful Wikipedians move all the scholarly references to that article, and then adjust that article to be consistent with its references. Later, other (or perhaps the same) Wikipedians update this list of "common misconceptions" to match that article.
• For people that want to go into excruciating detail, far more detail than is appropriate on a page like this, the link points directly to a more appropriate place to go into the details.

Earth's Core

I've just removed the following edit, which I assume was made in good faith:

Earth's iron core is not liquid (like the mantle) but solid, due to the pressure at the center of the Earth. Furthermore, the core may not be round as shown in textbooks but exists in a cube-shaped crystalline state of iron.

My reading of the article to which this links is that it is regarding the positioning of individual atoms within a cubic lattice, and does not speculate upon the overall shape of the core. I felt this warranted more comment than could be given in the edit summary. --Neo (talk) 21:49, 6 April 2008 (UTC)

Yeah ...it should be made clear that the core as a whole isn't cubical; rather, the arrangement of the atoms is. That's kind of a big difference. --FOo (talk) 21:57, 6 April 2008 (UTC)

How to get rid of this page.

I think this page should be removed. Pardon the harsh words but I think it serves little purpose other than for Wikipedians to flaunt their supposedly better knowledge than the "common" person.

There is no need for this article in the sense of being informative since a person does not think "Hmmm... maybe some of the things I think I know are false. I should go on Wikipedia to find me a place that tells me just how wrong I am... oh lookie here, a page that lists 'Common Misconceptions'... super!". To borrow a phrase from the computer software industry: there is no solid use case where this article is needed.

Further more we must ask: What is a "Common misconception"? The very title of the article shows its inherent POV problem when it tries to be a list of them since it is very difficult to show just what a "common misconception" is in the first place. Not only that but some of the explanations I have found here are common misconceptions themselves, such as that about space being cold... which it is not... or maybe it is(!) depending on how you define a temperature of vaccuum. This of course demonstrates that this issue is not "undisputed" as the article head claims.

Any information found on a specific subject in this article can - and should - be moved to the appropriate article for the subject. Once the information is "at home", it should be removed from this page to avoid duplicate information. And eventually this list will be empty.

After that is completed, this article can talk about the concept of 'Common misconceptions', such as modern urban legends, faulty information in chain emails and so forth. It should also show how a common misconception can arise through word of mouth, incomplete information being passed on, outright lies, et cetera. At most it should have one or two examples of a "common misconception" and these examples must be verified that they are indeed "Common misconceptions".

I think that this article should not be nominated for deletion. Instead it should be thuroughly reformed by careful and meticulous work. The information in this article should not be lost, only moved to its appropriate places.

Comments? What do you think? --J-Star (talk) 08:15, 7 April 2008 (UTC)

On the other hand, it could just be interesting and informative reading. I'll grant that a certain amount of editorial discretion is required to decide what's "common" and what isn't, though that hasn't turned the page into a disaster. I'm sure much of the information it contains is in other articles specific to the what the misconception involves. However, that doesn't preclude having it all collected into one interesting page as well. I didn't know half this stuff, and I should have, but I wouldn't have come across it just by randomly browsing the encyclopedia.

The article that you speak of, about the general origins and types of widespread misconceptions, could be a separate article, or appear at the top of this one. But I don't see how the encyclopedia would be better without this article than with it.--Father Goose (talk) 08:28, 7 April 2008 (UTC)

I'll grant you that it can be interresting read, and that you can stumble upon it... but that makes it a trivia article. Wikipedia discourages trivia.

I think that while the article isn't "disastrous", it certainly has quality problems, especialy with the concept of a "common misconception" being subjective. And as was shown recently on the page about Bernoulli's Principle sometimes there isn't even a concensus among those knowledgable about the subject what the actual explanation is.

Any information on a subject found here should be in the subject's article. It is unreasonable to think otherwise. Thus this article can supply only duplicate information found elsewhere in Wikipedia, which means this would be a Wikipedia article referenceing another Wikipedia articles, which is not acceptable by policy. And then there is the problem of syncronizing the information between the different pages since not everyone that edits an article on a subject knows that this page exists too.

I could find this page acceptable under the following conditions:

1) it is renamed "List of common misconceptions",

2) the bulk of the information is moved to the appropriate articles on the respective subjects

3) this list only headlines each misconception and then wiki-links to the respective articles. --J-Star (talk) 08:45, 7 April 2008 (UTC)

This list is useful as a means of keeping the junk out of other articles, and avoiding long lists of "what X is not" or "how X is misunderstood" in those other articles. A handy link to here serves better than clogging up the article about X. So I think it's better to retain the detail here - but I do think changing the title to "List of..." is a good idea. Snalwibma (talk) 09:06, 7 April 2008 (UTC)

If the information is "junk" as you put it, then why should it be in Wikipedia at all? Further more this page does not prevent "What X is not" to appear in the main articles anyway since not everyone is away this list exists. And a good written debunk-section in the main article does not "clog it up". In fact, I think this article here is a heck of alot more clogged by trying to debunk too many misconceptions in a much too small space. --J-Star (talk) 12:01, 7 April 2008 (UTC)

Wikipedia discourages trivia sections, as they are typically host to disorganized and unsourced information. I'm not sure it's right to declare that the information in this article must be in other articles as well, as some of this information may constitute an "aside" relative to other subjects (or go into too much detail), but still be an actual common misconception. Some of it does duplicate content found in other articles, though duplication is not against policy, nor necessarily a bad idea, depending on the subject(s) you're trying to present.

Renaming it "list of" is unnecessary, though not particularly objectionable.--Father Goose (talk) 10:40, 7 April 2008 (UTC)

I can't say I think this page is any more organized than the discouraged Trivia sections. Also, can you point to any information on this page that should not be in the subject's main page and specifically listed there as a common misconception (such as the Equal_transit_time_fallacy) or even as its own separate article? Please, give me examples. --J-Star (talk) 12:01, 7 April 2008 (UTC)

The "trains running on time" misconception might be too tangential a reference for Mussolini's article (it is in there, but only as an external link). But I would say it's a fairly common misconception, very worthy of this list.

The "10% use of the brain" factoid is also probably too hokey to put in the brain article, yet it's definitely an old popular myth also worthy of this page.

I think this page works fine with a mix of entries that are repeated in other articles as well as ones that are uniquely located here. It needs a bit of editorial intercession to keep it on-topic (the Thomas à Beckett one, for instance, is probably not "common" -- though I have heard of it), but most of it looks fine to me.--Father Goose (talk) 03:54, 9 April 2008 (UTC)

Editors frequently create lists of things to compare different information, or to collate information to make it easy to access. For example, many articles acquire "X in popular culture" sections. There are huge fights on WP about whether these sections, which are basically lists of trivia, should exist or not. If they are trimmed back, they reappear 50, 100, 1000 times again. There is no clear consensus that states these sections should be removed, or retained. For example, look at Frère_Jacques#Cultural_references and Frère Jacques in popular culture. Should this all go in the main article? Maybe, but it might be awkward to fold it in. People clearly are interested in it; it gets about 300 page views a month. And it might even be useful to someone.

Now consider the article, List of world's largest wooden ships. It gets about 4000 page views a month! All this information in this list could be put in the main articles. It is all redundant in a certain way. But people like to have a list like this to compare information and details. And there has been a lot of interest in this article by many people.

This article, or something like it, has existed on Wikipedia for quite a while. I have seen articles similar to this deleted, and then something like it was recreated. People obviously want this sort of article. It was viewed almost 2500 times last month, so people are obviously interested in it. We operate by consensus here, and by giving the public what they want, in a certain way. As redundant as this information is, obviously the public wants it in this form for some reason. And so, we have it.--Filll (talk) 12:35, 7 April 2008 (UTC)

Uhm, just because we get page hits doesn't automatically mean that this format is the optimal one or even a desireable one. If we went by the reasoning "page hits shows us the peple want it this way" Wikipedia would never evolve as long as poeple read the pages. And we don't know why they come here... is it because they seek information or - as I bluntly put it in the original post - to flaunt?

I'd also like to point out that while List-articles exist, they are named as such in the "List of..."-format (this article isn't); they also commonly have a bit of information about the subject listed (this article hasn't); and each list item is commonly short and links to the item's main article page if it exists (this article doesn't, at least not very often). The example you provided shows this clearly. --J-Star (talk) 12:57, 7 April 2008 (UTC)

Lot of recent changes to be checked.

• [1]--Filll (talk) 17:13, 28 April 2008 (UTC)

For the record, I agree with most of the simplifications performed during those edits (everything that was put in html comments), disagree with the change to British English (the policy on that is leave an article as you found it), and do not know the science well enough on the factual changes made to be able to express a useful opinion.--Father Goose (talk) 22:07, 28 April 2008 (UTC)

is this correct?

in the Evolution section, it says: "However, fossil discoveries of "recently" (as in, only millions of years ago) extinct species are, in the experience of paleontologists, rarely direct descendants of living species."

well, duh. surely "ancestors" was intended, rather than "descendants"? 71.248.115.187 (talk) 20:48, 10 June 2008 (UTC)

Edit war between User:Rracecarr and User:Jetstream_Rider over lift entry

I copy the discussion below from User_talk:Jetstream_Rider to help others follow the dispute. Rracecarr (talk) 19:21, 23 June 2008 (UTC)

Please discuss changes to common misconceptions rather than reverting. Basic physics says that the force required to defect air downward from a wing is EXACTLY the same as the lift force produced. Whether you say the lift is a result of the downward deflection or of pressure differences is a matter of semantics, but the claim that the downward deflection of air accounts for some of the lift but not all of it is simply wrong. Rracecarr (talk) 13:10, 10 June 2008 (UTC)

-See what I have written on your other discussion page. Excuse me for not quite getting the edit right and leaving it unsigned, but still getting used to the way Wikipedia works.

-If you are right, then how to you explain lift generated without downwash? (its possible and easy to demonstrate).

- The page on lift disagrees with you.

The lift page does not disagree with me. I just went and read it and it explicitly agrees. I copy from that article:

From Bernoulli's principle, the pressure on the upper surface where the flow is moving faster is lower than the pressure on the lower surface. The pressure difference thus creates a net aerodynamic force, pointing upward and downstream to the flow direction. The component of the force normal to the free stream is considered to be lift; the component parallel to the free stream is drag. In conjunction with this force by the air on the airfoil, by Newton's third law, the airfoil imparts an equal-and-opposite force on the surrounding air that creates the downwash. Measuring the momentum transferred to the downwash is another way to determine the amount of lift on the airfoil.

Rracecarr (talk) 16:39, 10 June 2008 (UTC)

Lift

Rracecarr keeps stating that lift is caused by air being deflected downward. This is not the case. The classic Fundamentals of Aerodynamics by Anderson refers, as does the Wikipeida article on Lift and many other academic books on the subject (although some simpler books contain the false assumption that we are trying to correct in the first place). Lift can be generated without deflecting air downward, and integrating the pressure across a wing section gives a value almost identical to lift. This is easily visualised by using a bank of liquid manometers connected to pressure tappings on a wing in a wind tunnel.

If lift were to be generated only by deflecting air downward, the wing section would be almost incidental, instead of being pivotal. If a thin wing section is used or simple plate is used, that deflects air downward, the amount of lift generated incredibly small compared to an aerodynamic wing section with a curved top surface that produces the same amount of downward deflection. If lift were to be caused by conservation of momentum, then in steady state the amount of air deflected downward would be far larger than the actual amount of air accelerated by the top surface of the wing. My background is in Aerospace Engineering and flying and deflection of air downward is just not sufficient to explain lift, it is a common misconception though. Where do you get your information Rracecarr? —Preceding unsigned comment added by 92.233.116.39 (talk) 14:09, 10 June 2008 (UTC)

I copied the above from my talk page.

The best way to explain how lift is generated is up for discussion. I don't care whether or not the article says "lift is caused by downward deflection of air". From one perspective, it's true, but it's a little like answering the question "how does a car work" by saying, "the wheels push backward on the road". Well, duh--a better answer would explain something about where that force comes from. So if you want to take out that phrase, that's fine with me. But it is not fine to claim that the wing is pushed up more than the air is pushed down. That is not true. A given lift force acting for a given time on the wing implies an equal and opposite force acting for the same amount of time on the air, and that impulse causes a corresponding change in momentum of the air. That's fundamental physics: to every action (lift) there's an equal and opposite reaction (downward force on air). The rate of change of momentum of the air as it flows around the wing is exactly equal to the lift created. As long as you don't imply otherwise in the entry, however you want to explain the generation of lift (i.e. by pressure differences etc) is fine with me. Rracecarr (talk) 16:29, 10 June 2008 (UTC)

"-But it is not fine to claim that the wing is pushed up more than the air is pushed down."

- Why not? It must be. For there to be a resultant force on a wing, that is exactly what happens. In steady flight the wing is pushed up more than it is pushed down, it doesn't accelerate because the "equal and opposite force" is the weight of the aircraft. Lift opposes weight in normal flight, the aerodynamic force on the wing is bigger in the lift direction, otherwise lift wouldn't be produced. Lift is after all a resultant force of all the forces working on the aerofoil adding up in the direction normal to the free flow. In a climb, the lift produced by the wing is actually less than in steady straight and level flight as the downward component of the engine thrust adds to the resultant force to oppose the weight.

The equal and opposite counterpart to the lift force is not the gravitational force on the plane, it is the downward force the wing exerts on the air. According to Newton's third law, if A pushes on B, then B pushes back on A equally hard in the opposite direction. So, the air pushes up on the wing (lift) and the wing pushes down on the air. The equal and opposite counterpart to the weight of the plane is the gravitational force exerted by the airplane on the earth. The earth pulls the airplane downward, and, equal and opposite, the plane pulls the earth upward. That is not important in the discussion of lift, I just point it out to underline that the third law counterpart to lift is not weight.

NASA disagrees with you, see here http://www.grc.nasa.gov/WWW/K-12/airplane/lift1.html. Weight does oppose lift. Newton's law of "equal and opposite reaction" is NOT "equal and opposite force". When an aeroplane tugs a glider into the air, the equal and opposite force initially manifests itself as acceleration of the glider (see Mechanics of Flight by Kermode). After a while, when there is no acceleration, the force is the tension in the rope pulling equally on the glider and the tug aircraft. Similarly Lift opposes weight - when they are equal the aircraft remains level, when they are unequal, the aircraft climbs or descends, the "opposite" reaction manifesting itself in the climb or descent. Of course in a vertical climb lift is perpendicular to weight, in which case the thrust opposes weight, but in level or nearly level flight, lift opposes weight.

Downward force on the AIR does not imply downward force on the WING, as you seem to imply. Yes the WING is pushed up more than it's pushed down--I never said it wasn't. But the AIR is pushed downward exactly the same amount. Did you read the excerpt I copied from the lift article above? In particular the sentence Measuring the momentum transferred to the downwash is another way to determine the amount of lift on the airfoil.? Rracecarr (talk) 14:57, 16 June 2008 (UTC)

Yes I did, this is over simple and not quite actually true - see below.

-There is a component of lift generated by downwash. This can be removed from a wing (by having a slightly upturned trailing edge), yet lift is still produced. It is produced by pressure changes. This can be further explained by boundary layer control devices. If you have a suction slot in a wing, you can keep the downwash almost identical, but dramatically increase the lift by sucking away the "lazy" air of the boundary layer, allowing the air to stick to the aerofoil instead of separating. This separation control allows the pressure distribution (ie the pressure drop above the wing) to contiune for most of the wing surface instead of being destroyed. Taking away the downwash reduces the amount of lift, but it does not destroy it. In fact you can have upwash from the trailing edge and still generate lift - its inefficient so not used in practice. The main way lift is produced is by pressure chages, but downwash does have an effect.

Some of the mathematical tricks to explain lift are just that - tricks. They are models to help predict the flow. Since flow is so complicated, it is at the moment beyond even the fastest computers to solve analytically. The Navier-Stokes equations remain unsolvable, but the fact remains, if you fiddle with the pressure distribution around a wing and keep the downwash the same, lift is dramatically altered. That's why I initially edited the entry. Looking forward to your further comments. Regards.

Integrated pressure and downwash are not two separate components that each contribute to lift. They are two different ways of calculating exactly the same thing--the total lift. Ignoring downwash and integrating the difference in pressure between the bottom of the wing and the top gives the total lift--downwash may be ignored. On the other hand, you can ignore pressure and calculate the total lift just from the downwash--you'll get the same answer. Rracecarr (talk) 14:57, 16 June 2008 (UTC)

Have a look at http://www.grc.nasa.gov/WWW/K-12/airplane/foil2.html

Set angle to 3.88, camber to -2.6 and Thickness to 25.75. You'll see there is no downwash, but a force of 539lbs on the wing. Your theory falls short here.

Also have a look at: http://www.grc.nasa.gov/WWW/K-12/airplane/presar.html http://www.grc.nasa.gov/WWW/K-12/airplane/right2.html http://www.grc.nasa.gov/WWW/K-12/airplane/wrong1.html - follow the forward arrow for some extra theories http://www.grc.nasa.gov/WWW/K-12/airplane/downwash.html http://www.grc.nasa.gov/WWW/K-12/airplane/bernnew.html

you'll see that Newton and Bernoulli (Force and Pressure) both have validity. HOWEVER, the Newton explanation does not talk about mass flow in a downward direction, which would be required for the "air deflected downward" theory of lift. Newton's equations can be used to determine lift, but the key is that the flow is turned, causing a velocity change, causing a presssure change.

I'll quote here: "Lift and drag are mechanical forces generated on the surface of an object as it interacts with a fluid. The net fluid force is generated by the pressure acting over the entire surface of a closed body. The pressure varies around a body in a moving fluid because it is related to the fluid momentum (mass times velocity). The velocity varies around the body because of the flow deflection described above."

So turning the flow is important, but only because it generates a change in velocity which in turn generates a change in pressure. There is no mention of "air being deflected downward" only air being deflected causing a pressure change due to velocity changes.

I repeat: Newton's third law requires that the downward force on the air is equal to the upward force on the wing.Rracecarr (talk) 19:41, 19 June 2008 (UTC)

No it doesn't. You have a fundamental misunderstanding of Newtons Law. The force on the aeroplane in steady flight is the same, lift being one force and weight being the other. If the upward aerodynamic force on the wing were the same as the downward aerodynamic force on the wing, there would be nothing to counteract weight. Lift and weight are equal and opposite in steady flight. In fact there has to be a resultant force on the air, as it accelerates. F=ma, so there must be a force for acceleration to happen. If all forces were equal and opposite, then nothing would ever speed up or slow down. I say again, the "equal and opposite" reaction is not nescessarily a force, but could be an acceleration.

Did you look at the flow simulator? Did you read the bold bits from NASA's website? NASA disagrees with you, the flow simulator shows you are wrong. In fact, you can see on the flow simulator that the upwash is greater than the downwash for the example I gave, so by your theory there should be negative lift. This is not the case. Lift is not caused by "flow being directed downward" and using Newton's laws to calculate lift is about conservation of momentum, energy and mass leading to pressure changes. It is not about the vertical component of downwash. I can't think of a better place to show you that than NASA themselves - if you don't agree with them, then take it up with them yourself, but please don't edit my wiki entries, as I have experience and the academic backup to prove what I write is true.

I do not have any more time to argue. I will continue to revert bad physics. That's what I do.Rracecarr (talk) 11:48, 20 June 2008 (UTC)

If you can give me a place (not Wikipedia) that shows lift is created buy "air being deflected downward" I'll agree. Until then (and there won't be a time) you are simply wrong. Newton and Bernouilli can be used to investigate lift, but its not a "downwash equals lift" argument.

Here you go. Rracecarr (talk) 23:55, 22 June 2008 (UTC)

Please stop adding unsourced original research (i.e. misinformation) to the common misconceptions article. It is not true that the lift force on a wing is different in magnitude from the force on the air required to create the downwash. But the fact that it's wrong is almost beside the point. It is against wiki guidelines to add material without a source. If you can't find a source that supports the crap you want to add, you must not add the crap. Rracecarr (talk) 00:25, 23 June 2008 (UTC)

What do you mean? Is referencing NASA material not sourced? What about Mechanics of Flight by Kermode mentioned above? I'll add some more references, but you pointing me toward an amateur RC yacht racers page is hardly likely to trump NASA and the most respected Aerodynamics author of our generation. I've now reference the US Navy, a world renowned test pilot, a basic aerodynamics teaching book, the standard text for most university aerodynamics courses and NASA. I'm keen to get the right thing down here, and not for personal gain. I keep bringing up references, bringing forward intellectual discussion and you keep reverting citing a single Wikipedia source, which is in itself unreferenced for the sentence in question. Can we take it to a third person who is a specialist and get another opinion? Just reverting each others stuff is hardly progress. My changes are now properly referenced to textbooks I have to hand and to websites with good technical basis. I could find others should it be required. I have no problems if you show me to be incorrect, but I will need proper sources from reliable places to convince me, as I spent 4 years at University and countllss times in windtunnels researching and learning about lift and the factors that effect it. I'll say again, Newton's equations can be used to determine lift, but its not about "downwards" momentum, you need to consider the momentum of the whole control volume around the wing, which in turn deals with pressure change albeit not in a particularly obvious way. If downwash is causing lift, then pressure changes cannot, otherwise the two would algebraically add and you would have twice the force actually measured. Bernoulli and Newton's equations eventually land up in the same place, even though the initial approach is different.

Please supply further references for your reversion, stating why you think the sources I have stated are wrong. What I have referenced here is taught at graduate and postgraduate level and is experimentally verifiable. I cannot see why you need to continually revert, stating one unreferenced sentence in the Wiki lift (force) article.

You are trying to institute the change to the article, so you are the one who needs to supply a source, which you have not done. Yes, you've supplied plenty of sources, but none of them support what you say. You claim that the force required to create the downwash is different in magnitude from the lift force. You have never supplied a reference for that incorrect statement. If you persist in adding unsourced material, you may eventually be blocked from editing. Rracecarr (talk) 18:53, 23 June 2008 (UTC)

(outdent) I have requested a third opinion. Rracecarr (talk) 19:02, 23 June 2008 (UTC)

I have also requested input from WikiProject Physics. Rracecarr (talk) 19:12, 23 June 2008 (UTC)

It doesn't seem appropriate to continue copying discussion from Jetstream's talk page here. If interested, read it there.Rracecarr (talk) 04:22, 24 June 2008 (UTC)

Technology / Transportation -- on flight

Please mention Gustav Whitehead (Weisskopf). It appears even he has been able to fly a "heavier-than-air craft capable of controlled and sustained powered flight" before the Wright Brothers did. It also appears that the Wright Brothers have met with Whitehead to discuss his (Whitehead's) work on flight.

src: http://en.wikipedia.org/wiki/Gustav_Whitehead

08:06, 16 December 2008 (UTC)