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Comment Book Archive: Year 2000

K-6 Science Misconceptions Page

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i see where your going with the misuse of the word electricity. with a public school education im used to being treated like i dont matter. but how you said the scientist just gave up of correcting this mistake almost proves that no one cares about the public school educatinal system. a stand should be take. at least to give the learned a chance to learn and understand right.
ryan <3434>
fellsmere, fl USA - Saturday, December 30, 2000 at 00:34:03 (PST)
Have you done much "work" on energy misconceptions taught in grammer school science? How should we teach kids about what energy is (ie., a property of objects, or a magical "substance") and how it is transfered?
don yehling
columbus, oh USA - Friday, December 22, 2000 at 10:01:14 (PST)
What is "back EMF"? Is it related to "time reverse" waves?
Roy Smith <Synchron4ataol.com>
Riverside, MO USA - Thursday, December 21, 2000 at 11:04:02 (PST)
Build your own high brightness white light solid state lamp only $1.75 each 5mm over 5 candle power 33 AA batteries will last days of none stop use. Will light up a whole room. easy to build I give plans and free resistor per order.
Paul R. Wilcoxson <whiteLEDsataol.com>
Watervliet, MI USA - Thursday, December 21, 2000 at 09:10:00 (PST)
I would disagree slightly with your explanation of why wings generate lift. The best explanation of the subject can be found in John Anderson's "Introduction to Flight." He explains how the only physical way that the air and body can communicate with each other is through the pressure and shear stress distributions acting on the body surface. It is these quantities that produce the aerodynamic forces of lift (pressure) and drag (shear stress). What you call the Newtonian explanation is really an effect of lift, not a cause. What really happens is that the air pressure pushes on the surface generating lift (as in the Bernoulli explanation), and in the act of generating lift the airfoil pushes back on the air creating the downward deflection you speak of. Thus it is not the downward deflection of air that is creating lift, but the production of lift through the pressure distribution that creates the downward deflection. You are correct in believing that the most fundamental explanation for how any thing works can be derived from basic Newtonian physics, but in the case of an airfoil, you must consider those Newtonian forces acting at the molecular level at the body surface, not at the macroscopic level of the body in the flowfield. If anyone wants to learn more about aerodynamics or aircraft design, visit the AircraftMuseum dt com Question of the Week.
Jeff Scott
Ridgecrest, CA USA - Monday, December 18, 2000 at 10:55:08 (PST)
Hey you Airfoil fanatics!

Drs. Anderson and Eberhardt just came out with a new book. I haven't seen it yet, but if it's like their paper , it has to be good. See it at amazon
William Beaty <>
Seattle, WA USA - Sunday, December 17, 2000 at 13:49:06 (PST)


i AM IN THE LAST STAGES OF developing A device that removes pollutants from burning of almost anything.Now I need help in electrocuting the remaning gasses,(possibly electrostatic high voltage.)Please advise. Howard
Howard Plouff <digitaldataaataol dt com >
Morriston,, FL. USA - Friday, December 15, 2000 at 07:36:12 (PST)
I recently played a little mind game with myself. I tried to imagine a world totally void of inertia. Think about it, absolutely NOTHING works! Thank God for inertia!
Mike Gray <mikeatxrayheads.com>
Amery, WI USA - Wednesday, December 13, 2000 at 06:51:43 (PST)
Does a witches broom produce lift like a wing? Do we even know what the birds and the bees do?
Mike
USA - Tuesday, December 12, 2000 at 10:00:33 (PST)
Bernoulli vs. Newton (airfoil controversy) - In other words, bees can't possibly fly?
Bill Momsen <nbrass1atearthlink dt net >
N. Ft. Myers, FL USA - Tuesday, December 05, 2000 at 19:31:21 (PST)
Carlton, Isn't 50% of a perpetual motion machine still a perpetual motion machine? (Half of infinity is infinity.) If you seriously need funding, I can help you out in exchange for your soul. But if you're just another swindler trying to make a buck, I've got a job opening for you down here. Of course, we'll have to teach you how to spell first...
Satan <satanathell.com>
Hell, MI USA - Monday, December 04, 2000 at 18:16:00 (PST)
Two notes about scientific method: Designing an instrument of improved sensitivity is not "doing science" but "doing technology". Scientific method is not concerned about ways used for proposing hypothesis, "...it's funny" is a good one. Scientific method is not concerned even about what's funny and what's not.
Goyo <goyodiazatteleline.es>
Albacete, Spain - Sunday, December 03, 2000 at 10:10:03 (PST)
why do you not have any pictures of electricity? you need to add pictures to your web site
Harry Dooley <harrydooley18athotmail dt com >
USA - Tuesday, November 28, 2000 at 05:42:35 (PST)
I Have found the key to perpetual motion.The reason Perpetual motion has never worked is the fact of gravity and bearing resistance but I have found a way to work with gravity to make this a reality. I am aproximatly 50% completed and have ran out of funds and I'm looking for an invester.If you are interested in talking with me on this matter then Email me or you may write or call at 912-496-3201. Seriously, Carlton Dasher
Carlton Dasher <1dowlingatbellsouth dt net >
Folkston, Ga USA - Friday, November 24, 2000 at 11:47:46 (PST)
this is really excellent material. i have forwarded your url to two lists that serve the needs of parents and educators of gifted and highly gifted children. they are going to love this material.
Jim Shirey <jshireyatfrognet dt net >
athens, oh USA - Tuesday, November 14, 2000 at 03:56:03 (PST)
Nasa says that lift is created when a fluid is "turning." They show a fluid flow past a cylinder. When they "turn" the cylinder lift is created. I interpret "turning the fluid" as the same thing as "stretching the streamsheet." An airplane flies be cause of "stretched streamsheet" above its wings. The more the stretch, the more the lift. Stretch it too much and it snaps like a rubber band and lift is destroyed. Hot air has more "stretch" than cold air. Place hot air in a hot air balloon and you will fly. How is "flight" defined? again. I don't remember what you said.
Mike Genereaux <mdgenereauxativillage dt com >
Las Vegas, NV USA - Monday, November 13, 2000 at 08:35:13 (PST)
Here's some more: A typical cruise angle of attack is something like three degrees. Twelve to fifteen degrees is where airfoils usually stall. But textbooks (and your web page) show a picture of an airfoil at either zero angle of attack or about ten to twenty degrees. The angle is purposely exaggerated to show that it's not zero. But at cruise speed, airplanes only need a small lift coefficient (angle of attack) to achieve the same lift (equal to weight for level flight), since lift is proportiona l to velocity squared. So a small change in angle of attack (say one degree) can have a large change in lift (say 30%).

Stall is when the flow over the upper surface no longer follows the curve of the airfoil. It separates and creates turbulence. A stalled wing can still produce lift, but not as much and at much higher drag. Drag is counteracted by thrust from the engin es, so higher drag means higher fuel consumption, which means higher cost to the operator. Stalled wings are also are more difficult to control.

Another thing I think might be confusing is that an airplane climbing at fifteen degrees does not have an angle of attack of fifteen degrees. The angle of attack is the difference between the attitude of the plane and the direction it is traveling. So w hen the plane is on a constant fifteen degree climb, the angle of the wing from horizontal minus fifteen degrees is the angle of attack. It's kind of like popping a wheelie on a bike. If you're going up a thirty-degree hill with both wheels on the road, you're not popping a thirty-degree wheelie. You're at zero angle of wheelie.
Greg Schmidt <g__schmidtathotmail dt com >
Seattle, WA USA - Saturday, November 11, 2000 at 17:02:12 (PST)


Things that should be stressed: 1) Aerodynamic lift is a force perpendicular to velocity. Drag is a force along the same direction as velocity. Do not confuse up with lift. In a vertical dive, drag is up. 2) The curvature of the camber line is what matters, not the curvature or length of the upper and lower curves of an airfoil. Camber is a measure of relative curvature between the two. The confusing thing to some people is that a symmetric airfoil and a very thin curved wing each have the same curvature for the upper and lower surfaces, but one in opposite directions and the other in the same direction. This difference in direction is taken into account with camber. 3) Air flowing above and below the wing does not have to rejoin at the trailing edge. The air over the top of a lifting wing does move faster, but not fast enough to catch up totally. So where does the extra air piling up on the bottom go? Around the e nds of the wingtips. This is where wingtip vortices come from. 4) The assumed incorrect implications on your web page are a result of ignorance - attempting to use a single example airfoil and angle of attack value to explain a range of scenarios. 5) F=ma. The lift on a wing is a result of the air trying to get out of the way of some object coming through it (downwash). 6) F=PA. The higher pressure on the underside of a wing is literally pushing it up. The lower pressure above is not pushing down as hard, so the difference is lift. This is also why air tries to escape from the lower (high pressure) surface to the uppe r (low pressure) surface around the wingtip, creating vortices. Wingtips are specially designed to take advantage of this flow to create more lift/less drag. 7) It's best to learn how things work, rather than assume something you think is right and try to prove it. Look at evidence. See what trends emerge. If new evidence conflicts with your current understanding, try to figure out what is different about t he situation than what you experienced before. This may require a whole new theory or just modifying the old one to a special case of a more inclusive theory. In this case, I think it's more the latter.
Greg Schmidt <g__schmidtathotmail dt com >
Seattle, WA USA - Saturday, November 11, 2000 at 12:34:43 (PST)
Just to clarify, the lift coefficient is not constant for a given wing, it still varies with angle of attack. But the relationship between lift coefficient and angle of attack is always the same for a given wing. The relationship changes if you use a different airfoil or extend flaps.
Greg Schmidt <g__schmidtathotmail dt com >
Seattle, WA USA - Friday, November 10, 2000 at 17:42:33 (PST)
I've read a lot on this page on the debate about why an airplane wing produces lift, and I'll try to explain the best I can for everyone. There are a lot of things at work here, since aerodynamics is complex. The argument of Bernoulli's principle vs. angle of attack cannot be resolved by one being right and the other being wrong. They are both right, and they work together to produce lift. But the angle of attack component is often overlooked.

Aerodynamic lift force is proportional to the local density of air, the velocity squared, the wing area, and the lift coefficient of the wing. The lift coefficient is a constant for any given wing, but changes if you modify the curvature of the airfoil or add flaps or winglets or other high-lift devices. As long as the wing isn't stalled, the lift coefficient is essentially a linear function of angle of attack. But the value of the lift coefficient (and therefore the total lift) when the angle of attack is zero (level flight) is not necessarily zero. This value depends on the airfoil curvature of the wing.

The camber line is defined as the curve halfway between the upper and lower curves of an airfoil. So at any point on the camber line, the upper surface and the lower surface are the same distance away. When the upper surface is curved and the lower surface is flat or less curved, the camber line is curved and we say it has positive camber. For a symmetric tear-drop-shaped airfoil (common for aerobatic airplanes), the camber line is flat. The amount of camber (how curved it is and in which direction) is what determines the lift coefficient at zero angle of attack, not the relative length of the upper and lower surfaces. A flat camber line has zero lift at zero angle of attack, but an airfoil with positive camber has a small amount of lift at zero angle of attack, though usually not enough to get off the ground.

But even if a wing has camber and flies at zero angle of attack, it still produces downwash, which is not shown in the "wrong" diagram on your web page. Downwash happens for any heavier-than-air vehicle producing lift. It's simple Newtonian physics. The mass of air being accelerated downward equals the lift force upward, which holds the aircraft from falling to the ground due to gravitational attraction. The difference between the higher pressure of air on the lower surface and the lower pressure of air on the upper surface multiplied by the wing area also equals the lift force upward. And that pressure difference can be created by both Bernoulli's effect (camber) and by tilting the wing at some angle of attack.

Here's the angle of attack perspective. A molecule of air far above or far below the wing will be undisturbed, so imagine these molecules as like a fixed ceiling and floor. The air above the wing has more space above the trailing edge and below the ceiling than above the leading edge, so it expands, lowering the pressure. Conversely, the air below the wing has less space between the trailing edge and the floor than below the leading edge, so the pressure is increased.

Lift force can also be downward. If the wing is at a negative angle of attack (more so than compensated for by any positive camber), the lift force is also negative. For an aerobatic plane flying upside down, the lift force is "down" to the pilot, but the weight to be offset is pulling "up," so they balance. To do this, the pilot points the nose "below" the horizon to fly at a negative angle of attack. The same maneuver could be seen from an upright nearby plane as a plane flying at a positive angle of attack with lift upward, weight downward, landing gear on top and an upside-down pilot. It's all a matter of perspective.

This has kind of grown from an explanation to a short thesis, so I'll end here.
Greg Schmidt <g__schmidtathotmail dt com >
Seattle, WA USA - Friday, November 10, 2000 at 17:35:01 (PST)


NOTICE: Nasa Glenn Research Center offers this cool JAVA-based airfoil simulator:
FOILSIM II
http://www.grc.nasa.gov/Other_Groups/K-12/airplane/foil2.html
They also have a page about the lifting-force controversy:
BERNOULLI VERSUS NEWTON
http://www.grc.nasa.gov/Other_Groups/K-12/airplane/bernnew.html

Bill Beaty <>
USA - Wednesday, November 08, 2000 at 19:11:31 (PST)
Your concept of Bernoulli's Ideal of an airfoil being incorrect are flawed. Although yes the downforce pushes the plane up not nearly enough to LIFT if (explain a 0x0 planform with your theory) also you lose effeciency since thsi down force does not push down souly it produces a rotational moment which is why we have a tail. Which brings us to tailess aircraft. This is where you theory really falls apart. Please explain how your AOA Theory can explain a reflex airfoil? It produces lift and yet NONE of the airflow is directed down ?
Chris Taylor Jr.
USA - Wednesday, November 08, 2000 at 15:52:57 (PST)
Your comments about the misuse of the word electricity contains the following statement "Instead it flows in the empty air surrounding the wires." What is "empty air"? Perhaps "empty space" would be better.
chuck
USA - Friday, November 03, 2000 at 22:07:36 (PST)
But cant you even prevent this static shock from happening.
Imran Shabir <badboys_118atyahoo dt com >
UK - Tuesday, October 31, 2000 at 06:20:14 (PST)
But cant you even prevent this static shock from happening.
Imran Shabir <badboys_118atyahoo dt com >
USA - Tuesday, October 31, 2000 at 06:19:47 (PST)
Why is it thought that a wing is the source of its own support, that it "produces lift?." Instead of as a tool that controls the support that already exist. Does science dabble in magic?
Mike G <mdgenereauxativillage dt com >
Las Vegas, NV USA - Saturday, October 28, 2000 at 09:01:26 (PDT)
i amdoing a report for school i need info about pyrotechnology thanks
jack <jack913099ataol>
USA - Wednesday, October 25, 2000 at 10:57:22 (PDT)
To whom it may concern, My friend and I are doing a project on water purification. We have to design and build a water filter that can remove solid particle from the water. My Friend has a machine that injects electrical charges into the water safely. The water turned a yello w at first, then green, then dark green and then, finally, almost a black. I was wondering, why would something like this happen? Is it because the electricity forms a visible barrier around the microscopic partcles making them visible. Why does it chan ge different colours before it turns to a black? Please write back as soon as possible,for my project is due soon. Thank you for your help. P.S. Our filter was able to change the yellow/green and black water back into the clear water you may drink at home! Good huh? Sincerly, Adam Guerra
Adam Guerra <adamwarathome dt com >
Brampton, ont Can - Thursday, October 19, 2000 at 18:28:11 (PDT)
Dear Mike, If a non-viscous fluid does not exist, then there is no way to place a wing in it to find out if it can fly. How can science make a statement of fact without physical proof?
Mike Genereaux <mdgenereauxativillage dt com >
Las Vegas, NV USA - Monday, October 16, 2000 at 07:26:21 (PDT)
In the most basic sense, lift is generated due to the fact that all fluids are viscous. The presence of viscosity properly fixes stagnation points on a body and allows a pressure difference across the body to be generated, resulting in lift. If fluids were inviscid, nothing would fly!
Mike Kerho <mikeateideticscorp dt com >
Torrance , CA USA - Friday, October 13, 2000 at 16:48:07 (PDT)
The problems with technical textbooks in general (including the K6 horrors) is that they are either written by physicists/chemists/Specialists or written by witless twits (like the K6 material). So, naturally the material will either be presented in o bscure poorly written language, including a demonstration of the writer's profound ignorance, if said writer turns out to be a wormheaded hack (not a true professional in the areas of science presented). Of course, all this is synergistic (harmonic), loo ping in on itself from generation until it produces a generation of ignoramuses at a moment when both teachers and textbooks become a homogneous mix of claptrap. Perhaps it also stems from man's desire to worhsip something, any-damn-thing if possible. And nature is no exception. Perhaps if we were to view nature's amazing laws in a different light, perhaps with some healthy disrespect, and call such laws cheap l ittle tricks, we can reduce their mystique, hence power to awe and confuse us. I, for one, tend to take the calmer Asimovian approach to science -- ingest it as you would plain humble brown toast. Keep everything out in the open, as plain as a brown bag lunch; and, yes, despite how the material can appear obscure and abstract, you can keep everything simple -- but not too simple or else you'll lose vital information. We need competent teachers and competent authors. And we shall get neither until we offer the same scale of pay in those job slots which the overblown salaries that our so-called entertainers get for the pig slop they put out over the airways and in nove ls have for too long enjoyed. Now I will drop off my soapbox to the next contender....
Mike Varela <mike.varelaatyale dt edu >
West Haven, CT USA - Wednesday, October 04, 2000 at 09:34:57 (PDT)
"I for one believe that there is a god, but he DOES play dice. But the Dice are loaded" Anthony W. Prince(1999)
Anthony Prince <capprinceatavalanchenet dt com >
West Jordan, Utah USA - Tuesday, September 26, 2000 at 16:38:58 (PDT)
if you like aviation visit www.aerodinamica.hpg dt com .br theory, galery, history and much more se vc gosta de aviação visite www.aerodinamica.hpg dt com .br teoria, faça vc mesmo, história e muito mais
Wally
USA - Monday, September 25, 2000 at 20:28:21 (PDT)
As I have understood BERNOULLI, air or any gas passing through a constriction increases velocity and decreases pressure. It is why ships passing too close collide, a person jumping from a building will tend to crash into the building, or why plumbing works the way it does. So if a wing has a longer path on top than on the bottom than the air on top is constricted and therefore lower in pressure causing the wing and anything attached to it to be pushed aloft. Isn't it true that no matter what the shape of the wing, be it flat on bottom or curved, as soon as you pass it through the air, one side will have high pressure and the other low?
Kevin Palan <tigger2atvoicenet dt com >
Hawley, PA USA - Monday, September 18, 2000 at 20:24:36 (PDT)
Flying, regardless of how it is done or who is doing it, will always and forever be magical and mysterious. However I will leave you with a challenge. Find me a non-aerodynamic shape and I'll show you something that flys. Show me a wing and I'll show you the Bird.
Michael D. Genereaux <mdgenereauxativillage dt com >
Las Vegas, NV USA - Thursday, September 07, 2000 at 08:16:59 (PDT)
Is someone able to give me some tip about where to find interesting articles about the Yusmar thermogenerator. Also if there are some interesting sights at the web. Thanks!
Andreas <ivarssonandreasathotmail dt com >
Sweden - Tuesday, September 05, 2000 at 07:26:52 (PDT)
The speed of light IS always 186,000 miles per second. In a medium, atoms absorb and re-radiate the light. This slows the propagation of light through the medium, but between the atoms the speed of light is constant.
C Conner
Mercer, PA USA - Thursday, August 31, 2000 at 12:11:55 (PDT)
A common misconception or misstatement by sports announcers is that someone "flexed their muscles". (I've never seen this in a textbook but it printed on sports pages) Muscles don't flex but they do cause a body movement called flexion when they contract!
Steve Clanton <slclantoatednet10 dt net >
Canton, Tx USA - Wednesday, August 30, 2000 at 11:47:42 (PDT)
Does Circulation Theory say that it possible to fly by using wings? Or does it say you cannot fly unless you have wings?
Mike G
Las Vegas, NV USA - Monday, August 21, 2000 at 08:15:53 (PDT)
love your site. but you should clarify the air-filled balloons experiment. actually, the air in the nearly-full ballon is compressed more than the air in the full-to-the-point-of-feeling-hard balloon (although your assumptions about the weight may be c orrect. You can test this effect by attaching two filled baloons together by means of a hose so that no air can escape. Rather than equilibrating to equal size, the balloon with less air will push its contents into the full balloon. This is due to the increased pressure of the thicker rubber in a less-full balloon.
scott <hirschathaas.berkeley dt edu >
berkeley, ca USA - Tuesday, August 15, 2000 at 22:38:43 (PDT)
Suppose one were to build a helicopter with blades at a permanent angle of attack. The helicopter is then controlled by speeding up and slowing down the blades. Now suppose we get the helicopter at a very high altitude, and then, cut the power, as the helicopter descends will the blades remain spinning? Or will the blades slow down, stop and then reverse direction? Will the blades slow the descent like a conventional helicopter would? What if the blades were flat like a ceiling fan, would that make a difference?
Mike
Las Vegas, USA - Tuesday, August 15, 2000 at 20:37:59 (PDT)
Thank you for the excellent articles. I found, that similar misconceptions are aboundant on the effect of te V-for of a wing. I fopund these wrong explanations in old textbooks and also, they can be found in books about model ariplanes. The wrong explanation is, that if an airplane tilts, the projection of the lower wing increases. Everybody, who has observed the effect of just a small V-form can see, that the effect is much bigger. Also, there are many wrong articles about the induced drag and totally wrong pictures of the airflow around a wing with elliptic lift distribution. Also, there are experiments of model builder who try to give the wing a geometry, where the vortices which produce the induced drag cnacel. I would like to get more data about the boundary layer, how thiock is it for a normal model airplane and do laminar airfoils really work for model airplanes.
Johann Joss <johann.jossatuptrend.ch>
Zurich, Switzerlans - Monday, August 07, 2000 at 11:45:30 (PDT)
About recombining a prism's rainbow of colors using the same prism: If I directed several beams of individual colors into the prism, at the angles where each color would emerge if a white light were shone into the prism, would the prism then combine th e colors into a beam of white light?
Richard Gabel <richardgabelatnetscape dt net >
state college, pa USA - Wednesday, August 02, 2000 at 10:52:21 (PDT)
When you place a helicopter inside a sealed box, the helicopter is in another field, if that field is the same as the earth's field, it can fly inside the box. A helicopter cannot reduce atmospheric density inside the box to make it become supported by the field outside its box. Take a helium balloon and place it inside a box, and then place that box on the moon. The box will not rise when it is on the moon because there is nothing on the moon to push it up. However, if I take a lightweight box, on the earth, I will find it in a field surrounded by random moving air particles. If I apply a force to these particle I will form streamlines. If I apply even more force to the streamlines they will accelerate. If streamlines accelerate, atmospheric pressure will drop in that region, via Bernoulli's principle. By placing these accelerating streamlines on the topside of a lightweight box, that box will hover. Since the box is not contributing any force to keep itself hovering I have to conclude the atmosphere is supporting it. I furthermore conclude that airplanes are not supported by their wings. Rather they are supported by the atmosphere, and they control that support by their wings. Thanks, Mike
Mike Genereaux <mdgenereauxativlillage dt com >
Las Vegas, NV USA - Saturday, July 29, 2000 at 07:37:36 (PDT)
About gases (see below): the goal is not to be correct, the goal is to EXPLAIN something to students without confusing them. In this case, the goal is to explain how gases differ from liquids and solids. Gases do not expand to fill a container, instead GASES IMMEDIATELY EXPAND TO FILL A VACUUM. Liquids do not. This explanation only works properly if the "container" contains a vacuum. If you put some air into a vacuum, it expands at hundreds of meters per second. That's one way to prove that air is a gas. If you put some liquid or solid into a vacuum, it does not expand like that.

Bringing the topic of diffusion into the explanation will cause confusion. If you squirt some CO2 into a room, it sits where you put it, and only after minutes or hours will it DIFFUSE throughout the rest of the air. This slow diffusion has nothing to do with the compressibility of gases. And besides, diffusion is not a characteristic of gases, it is a characteristic of fluids in general: put some dyed water into a water-filled container, and after a few hours the dyed water "expands" to fill the container. So, have we proved that water is a gas, since all gases "expand" to fill their containers? No.
bill beaty <>
USA - Friday, July 28, 2000 at 10:26:08 (PDT)


Thank you so much for this site. I never cared much for the specifics of how things worked until now.
Lute
USA - Wednesday, July 26, 2000 at 18:09:02 (PDT)
I don't believe the misconception about gases filling their containers is a misconception at all. The carbon dioxide fire extinguisher example you quoted, if analyzed properly, shows the point. The carbon dioxide will in fact fill the room-it does no t stay at the floor where it was squirted. A better way to state the idea is to say that a gas will fill its available space, which in the context of the definition of an ideal gas, is the entire container. This filling may not take place instantaneousl y, but the gas will eventually diffuse so that it's concentration is uniform throughout. The Ideal Gas Law (definitions), Dalton's Law of Partial Pressures, and the Second Law of Thermodynamics all point to a gas having no volume of its own. This, then IS the macroscopic difference between liquid and gas. Regards, JR
John Riley <dsbscienceatcetlink dt net >
Rock Hill, SC USA - Wednesday, July 26, 2000 at 05:44:05 (PDT)
I just wrote up a brief version of the CORRECT explanation of airplanes based on Bernoulli's concepts. See:

AIRFOIL EXPLANATIONS

Here's a thought. If airfoils work like balloons, if they work by static forces only, then a helicopter could still fly if its rotor was placed in a box. After all, if we place a balloon into a large box, the balloon does not push downwards on the interior of the box as the balloon rises. If the box has low weight, then the balloon can lift the entire box upwards! So, if a helicopter attains lift only because of pressure fields and not because it flings air downwards, then we can place a helicopter into a sealed box, and the whole box will rise into the air! There will be no downdraft coming from the sealed box as it hovers in the air! If the box was fairly thick (but light), the helicopter would be totally silent. Now wouldn't THAT make a great toy, if you built a small one.


In reality, Newton's laws insist that a helicopter can do no such thing. Helicopters don't fly by bouyancy, they fly because they launch a stream of air downwards, and they are lifted by the reaction force. Bernoulli's equation is important because it describes how the deflected air creates a pressure difference on the wing's surfaces. But without deflection, the circulation pattern vanishes, and without circulation, the upper and lower flow velocities become the same.


Another thought: Bernoulli's equation is based upon Newton's laws, and it therefore will describe the same things that Newton's laws describe. If a stream of air is blowing across a surface, and its low pressure applies an upwards force to the surface, AN EQUAL DOWNWARDS FORCE MUST APPEAR ELSEWHERE. Newton's 3rd law is not violated by the "Bernoulli effect." It is impossible to lift yourself by pulling upwards on your shoelaces. For the same reason, whenever the "Bernoulli effect" sucks an object upwards, it must fling some air downwards at the same time. The trailing edge of a cambered wing will create a downwash at the same time as it causes the "circulation" which forces air to flow faster over the upper surface of that wing.
W. Beaty <>
Seattle, WA USA - Saturday, July 22, 2000 at 14:57:10 (PDT)


To Bill Beaty: F=ma -- everytime. Thanks!
Alton <altonjatflash dt net >
Plano, Tx USA - Sunday, July 16, 2000 at 17:40:15 (PDT)
To Mike Genereaux -- Mike a wing acts just like a fan-blade or propeller, which moves air. A wing simply thrust the air down and the resulting force on the wing is lift.
Alton <altonjatflash dt net >
Plano, TX USA - Sunday, July 16, 2000 at 17:29:39 (PDT)
Another misconception is that all things exist in three forms, solid, liquid and gasseous. The typical example is Ice, water, and steam. However, the borderline between the three states is much less dramatic than the example of water. Many substance s go though a transition between phases, like butter, or ice cream, which become progressively softer as the temperature rises. The transition between solid and liquid is one of the most interesting phenomena to investigate, as the deformation of soft solids (greases for example) and highly viscous liquids (glass for example) are interesting to measure. This is the field of rheology, which even has several journals and a society (Society of Rheology) devoted to its study.
Dave Alexander <VQUEST95atAOL dt com >
Wappingers Falls, NY USA - Sunday, July 16, 2000 at 12:38:05 (PDT)
Hi Bill, Have you ever seen a lumberjack on a log in a lake? When he gets the log spinning he will try to stay on for as long as he can. When the log is spinning just as much water will go upwards as downwards right? Does the log sink or float higher? I still don't see how you expect your huge spinning heluim disk will be different? When a carpenter makes a cut, the "cut" is made where the blade makes contact with the wood correct? Lift, is made where the air makes contact with the wing, correct? Contact forces, right? Try this. Take a flat wing. Mark off two points a few inches apart on it. Now place an accelerating air flow between those two pionts, at the surface. Lets say at one point you had 100 m/s and at the other 125 m/s. Will the pressure be lower at the 12 5 m/s point? Will I see an upwash, downwash or a vortex? How do you get a mass of air to go from 100 m/s to 125 m/s on a flat surface? Or even a curved surface? I still do not see the downwash theory as holding any water. If a wing throws air downwards so it can go upwards where does it get the air so that it can throw it downwards? How does it grab these packets you talk about and how does it throw them downwards?
Mike Genereaux <mdgenereauxativillage dt com >
Las Vegas, NV USA - Thursday, June 29, 2000 at 09:52:10 (PDT)
You say "Many books contain a incorrect experiment which purports to demonstrate that air has weight. A crude beam-balance is constructed using a meter stick. Deflated rubber balloons are attached to the ends, and the balance is adjusted. One balloon i s then inflated, and that end of the balance- beam sags downwards. Unfortunately this experiment lies. When immersed in atmosphere, buoyancy causes full and empty balloons to weigh the same. The experiment secretly relies on the fact that the air within a high-pressure balloon is denser than air within a low pressure balloon." But if the air was weightless, the weight of the baloon with more air would be the same as that of the other one, i.e. zero! So in my opinion the experiment proves what it's supposed to.
Peter <savelievattctc dt com >
USA - Sunday, June 25, 2000 at 12:31:07 (PDT)
Mike G. wrote:
> Dear Bill, I do not follow the difference between 2d and 3d

Hi Mike! In a "2D" situation the air can only move up and down or forwards and back, it does not move along the wing. If you place a crossection of a wing into a narrow wind tunnel, and the ends of the wing are against the walls of the tunnel, that's a "2D" situation. If you place an entire model airplane into a wind tunnel, and the tips of the wings are far from the walls, that is a "3D" situation. > Also, I have extreme difficulties believing a "wing"
> launches packets of air downwards

My explanation is here
Also look here for photographs of the downwards-moving air.

> What is your definition of flight? Does a hot air balloon fly?

In physics we have forces caused by F=MA, but we also have "contact forces". When a rocket hovers above the earth, it is flying because of F=MA, since the rocket accelerates exhaust parcels downwards and is lifted upwards as a result. When a ship floats on the ocean, no mass is accelerated, and the ship stays up because of contact forces between the ship, water, and earth. The same is true of a balloon: it hovers because of contact forces between the balloon, the air, and the earth.

Airplanes, helicopters, and rockets are different. All of these fly because of F=MA forces. All of these are accelerating gasses downwards in order to be forced upwards. The rocket provides its own gasses, but this makes no real difference, since the ACCELERATION of the gasses and the F=MA law are critical, and the source of the gasses is not.
Bill Beaty <>
Seattle, WA USA - Thursday, June 22, 2000 at 12:32:57 (PDT)


Well! Is light composed of radiations of the sun or particules of photon... Both theory explain different effects in biology and physical sciences... Why couldn't we accept that both Bernouilli and Newton were right in there different conceptions of lift! If You show a cup of coffee from under to somebody he'll tell you it's a circle while others will see a cylinder... Who's right? I think that there's not a reality but realities that coexist depending of point of views! Are you ready to accept other point of view than yours... it just depends if your open minded or not!!! Anyway! It's a fact that vortices are down after wings so there's a downwash stream after a wing passage in the air And the vortices are created by a difference of pressure at wing ends between "intrados" an "extrados" so this difference of pressure exists and is created by something like Bernouilli's principle... Of course there are problems of viscosity and thermal exchanges that change the problem and we also must remember that air is a complex fluid with differences of density, moisture, temperature .... in very short distances or volumes.... So i'm not shocked that results aren't exactly wath was expected in theory based on perfect gases laws!
Philippe LE TIEC <tyfilouatnetscape dt net >
LA TUQUE, Qc CANADA - Tuesday, June 20, 2000 at 22:19:44 (PDT)
Technetium - not found on earth? It may not be naturally occuring, however it is found in the Nuclear Medicine department of many hospitals.
Linda Beauchamp <BeauchampLMatbigpond dt com >
Townsville, QLD Australia - Friday, June 16, 2000 at 22:14:50 (PDT)
> I'm pleased to find some agreement, any agreement, on the
> upwash/downwash matter, if only as it applies to 2-dimensional
> flow. I'm with you that far.

I've also heard that it applies to "ground effect" flight, where the aircraft is less than one wingspan from the ground. In this situation the field of pressure/flow supposedly causes most of the lift, and the surface of the earth can "feel" the pressure- footprint of the aircraft.

> What happens when we, say, cut a finite bit of span out of
>infinite wing, is that air flows around the ends, n'est-ce pas?

But other things also occur: the air was flowing downwards at the time it left the trailing edge of the wing, and because of inertia it keeps going down. Air did try to flow around the ends of the wing, and therefore after the wing has passed, the air is left with a structured flow: moving down in the center, and upwards at the edges, but with an overall downwards motion. It forms a pair of huge vortices.

> There is no reason for this trailing vortex to do anything but
> trail straight back, no up, no down.

The reason it moves down is inertia, and experiments show that the air behind an aircraft is moving downwards. When an aircraft flys horizontally over fog, it throws air downwards, which punches a slot in the fog. See this famous GIF IMAGE. Also see the index of fluid dynamics photos

> Do you not see that the wing CANNOT force air downwards. There's
> air already there. If air were forced down it would pop back up, like a roostertail behind a boat

Aha! That is a very important point. In a 2D world, your reasoning is correct: if the wing tries to push a stream of air downwards, it must force the entire atmosphere to move downwards as well. But in 3D the air has an extra dimension of freedom, and it can get out of the way of the downwards-moving trail. The wing leaves behind a long, double-cylinder of air which moves downwards, and the rest of the atmosphere can easily slip upwards as these cylinders move downwards. While it's true that there is ZERO net motion of air, the cylinders do move down, and momentum follows the cylinders of air, so SOMETHING is truely moving downwards.
Bill Beaty <>
Seattle, Wa USA - Monday, June 05, 2000 at 19:35:35 (PDT)


Dear Bill, I do not follow the difference between 2d and 3d. Is 2d a computer model? And 3d is a wind tunnel simulation? Also, I have extreme difficulties believing a "wing" launches packets of air downwards. How much air is a packet? What is its volume? What is its mass? What is the machinerey the wing uses to grab these packets of air and throw them downwards? Noticing that air leaving a wing has a horizontal component, what effect does this have on the wing? Does a wing gain a mass of air like a jet engine, and loses it as it is launched downwards? Why isn't this air traveling faster leaving the wing than it was from the leading edge of the wing to its highest point on the wing? Does not Bernoulli's principle work on top of the wing? Ho w do you explain flight from start to finish? What is your definition of flight? Does a hot air balloon fly? Does a wing experience buoyant forces? What is induced drag? What is parastic drag? Is overcoming parsitic drag a prerequisit for the develop ment of your definition of flight? Is a wing essential for flight? When a hurricane launches a car through the air, is the car "in flight"? I've got many more questions, this is enough for now, all I want to do is understand flight.
Mike D. Genereaux <mdgenererauxativillage dt com >
Las Vegas, NV USA - Saturday, June 03, 2000 at 14:04:21 (PDT)
I am a 13 year old student researching on how chemical reactions produce electricity. I would like to ask if you can email me some science information on the particular subject as the Internet does not have specific sites for this
Grace <grace_115athotmail.com>
singapore - Saturday, May 27, 2000 at 06:53:51 (PDT)
Dear Bill, I'm pleased to find some agreement, any agreement, on the upwash/downwash matter, if only as it applies to 2-dimensional flow. I'm with you that far. What happens when we, say, cut a finite bit of span out of infinite wing, is that air flo ws around the ends, n'est-ce pas? There is no reason for this trailing vortex to do anything but trail straight back, no up, no down. The wing must now, if it is to maintain the same amount of life, must increase its angle of attack slightly to compensate for that loss. Still the upwash equals the downwash, or v.v. Do you not see that the wing CANNOT force air downwards. There's air already there. If air were forced down it would pop back up, like a roostertail behind a boat, as soon as it passed the trai ling edge. Richard
Richard Miller <richardmilleratrocketmail dt com >
Santa Cruz, Ca USA - Friday, May 26, 2000 at 18:00:13 (PDT)
About the field theory of airplane flight...
I discovered an interesting thing this year. Flight in two dimensions is fundamentally different than flight in 3D, and if we focus too much on a 2D windtunnels or 2D computer simulations, we miss some important things. One of the important things: in 2D, the upwash exactly equals the downwash, and the wing does not deflect the air in the long run... but in 3D things are different. In 3D, the wing launches packets of air downwards. These downward-moving packets are found in the wake vortex behind the aircraft.

In two dimensions, there is no wake vortex. In two dimensions, a vortex is locked to the airfoil and extends to infinity (or extends to the distant ground.) In two dimensions, an aircraft can stay up because it makes contact with the ground via a field of dynamic pressure. But in 3D an aircraft does not do this. Instead it stays up by launching pieces of air downwards.

Here's a crude animation of moving chunks of air.

Why does smoke 'ring?' http://amasci.com/wing/smring.html
In the above webpage, refer to figure 2. Imagine it to be rotated 90deg so the red vortices move downwards. If air was visible, and if you flew behind an aircraft in flight, that's what you would see: the wings divert the oncoming air downwards, and it forms itself into a pair of counterrotating vortices which behave something like a "rocket exhaust". The wing throws air downwards, and it is lifted against gravity.

bill beaty <>
Seattle, WA USA - Thursday, May 25, 2000 at 18:43:36 (PDT)
In your section explaining how gases don't expand to fill their container, you state "All our containers come prefilled with air." I deduce from this you have never pumped up an inner tube, which, by the way, makes an excellent demonstration of the pr inciple.
Henry J. Hruby <hhrubyatattglobal dt com >
USA - Wednesday, May 17, 2000 at 22:06:45 (PDT)
Dear Bill Beaty, I have read two of your statements about "suction" and "blowing" in relation to airplane flight. Starting with your statement dated 11/3/1999 to H. Hurn you write "In theory it is possible to drink through a straw even in a vacuum en vironment." On 10/26/1999 you write "a "backwards rocket" which only sucks into an intake cannot fly. First of all where did you get the theory you can drink through a straw in a vacuum environment? I know "by experiment" that you cannot drink through a straw in a vacuum environment. That doesn't mean your "theory" is wrong it just means I can't prove it by experiment. Can you? If a "backwards rocket" can't fly but you can drink through a straw in a vacuum environment then that means one or both of your statements are wrong, you can't have it both ways. I asked Richard Miller what way an "S" shaped sprinkler should spin when you reverse the flow, do you know? Can you elaborate your explanation?
Mike Genereaux <mdgenereauxativillage dt com >
Las Vegas, NV USA - Friday, May 12, 2000 at 00:56:19 (PDT)
As a truck goes down the road it picks up a charge. The dirt on the road is attracted to this charge. You try to wash it off with a pressure washer and the stuff will not budge. You use a brush and the stuff will eventually come off. If you use a mild acid followed by an alkali it rinses off with a water hose. Are we dealing with static electricity? Ions? What? I'm told the process I stated reverses the polarity. Is this true? Is there a way to do the same thing without using chemicals? Maybe changing the polarity of the water before it hits the truck? Like an electrostatic paint sprayer in reverse?
John DeRosa <Hotwaterwizardataol.com or hotmail.com>
Stockton, Ca USA - Saturday, April 29, 2000 at 17:06:08 (PDT)
Dear Richard, It was is my intent to rush you to conclusions. I in no way thought the sprinkler problem was to simple or to obtruse for your understanding. The swimming pool is that field. Our job is to shed light upon the field effect of lift that i s in that field. When I did the sprinkler expierment I did not find a dynamic pressure. I increased the velocity vector to a very high degree. I searched for the acceleration vector and could'nt find it. The only vector I could find was the velocity v ector, mabe you can find the dynamic pressure when you do the expierment. I strongly disagree that the distribution of matter between planets and galaxies can support a lift field. One of the requirements is that the field at hand be under pressure. Wh en in space, Space Shuttles cabin still has the field effect of lift even though a lift against gravity is not neccessary. Streamlines, photos, and smoke representations will not represent what I had in mind as a field effect of lift. Many examples of th e field effect of lift allready exist. A hot air ballon, a boat floating on water, bubbles rising in a wine glass etc. I was thinking more along the lines of my expierments showing a flat board at zero angle of attack, that is flying, or a wing flying a t a negative angle of attack. These are the kinds of thing that need to be shown because, it is common beleif that those expierment are impossible. If the experts will just stop for a moment, a wing is a tool, the position of that tool to relative wind, angle of attack, are not Laws of Physics. Its to bad I don't have money, a large shop, or lots of time. Because you know what would happen Richard, improvments on my current inventions would happen, but the biggest part I would turn aviation upside down , that I can promise. I have probably given away many of my inventions by this discussion. I have always felt that the theory was more important than the inventions, because without proper guidence by a theory you will probably only spin you wheels. Unl ess you have some unique way of demenstrating the field effect of lift our discussion is over. Thanks a lot, its been fun. Mike
Mike D. Genereaux <mdgenereauxativillage dt com >
Las Vegas, NV USA - Saturday, April 29, 2000 at 09:12:16 (PDT)
Dear Mike, A proper response to your letter would require a lot more writing than I'm able to do at the moment. I like to take things one at a time, if possible, and nail them down. First the "S" shaped sprinkler, which, anchored to the ground, would turn in a c'clockwise direction as seen from above. With the flow reversed, which is to say drawing in water in your swimming-pool example, it would turn in the opposite direction, clockwise. That seems simple enough unless I've missed something to simpl e or too abstruse for my understanding. +++ Next Point: an experiment that will demonstrate the reality of a field effect. My first observation is that birds gonna fly and fish gonna swim whatever our theories are. Second observation is that there are to ns of illustrations, photos and smoke flow representations, which clearly show field effects. A typical such photograph will show the streamlines rising to meet the airfoil and separating or converging as they head for the lower and upper surfaces. They are obviously subject to discontinuities of some sort, and these discontinuities are aspects of the pressure field. +++ There are scalar as well as vector fields. Such things as the temperature of the room in which you sit can be, and typically are, given scalar representations. This would apply as well to any space, such as the regions between planets or galaxies, in which there was some distribution of matter. I wanted to stick, first, to dynamic pressures, then to vector fields, because these relate to the issue under discussion, lift. Richard
Richard Miller <richardmilleratrockemtail dt com >
Santa Cruz, Ca USA - Thursday, April 27, 2000 at 17:38:15 (PDT)
Dear Richard, Can you cut paper? Not without the application of a force. Can you create a vacuum within a field? Not without the application of a force. Can you reduce the required force to cut paper by first applying a force to a tool (scissors, k nife, shears etc.) then apply that force to the paper? Can you reduce the force required to create a vacuum in a field by first applying a force to a tool and then apply that force to the field? YES, YES, AND YES!!!! Dynamic, I believe means "in motion ", in comparision to static meaning "at rest". I do not believe you can have a dynamic pressure, either postive or negative without the application of a force. I believe that the "motion" in a dynamic pressure is an acceleration. Negative acceleration (slowing down) for positive dynamic pressure, positive acceleration (speeding up) for negative dynamic pressure. A pressurized tank is an example of static pressure. Before any pressure of any kind can be made a field must be defined. Outer space is no t a field. OK. We cannot have a low pressure without a high pressure within a field. I asked you for the results of an experiment. What direction does an "S" shaped sprnkler spin when you reserse the flow? Do you not know the answer to this dynamic fl uid flow problem? I did an experiment where I found the "field effect" of lift. It is very important to understand these experiments I present because it leads to an understanding as to how I arrived at my conclusion. Do you Richard, have an experiment to show and prove the "field effect" of lift? If so what is it?
Mike D. Genereaux <mdgenereauxativillage dt com >
Las Vegas, NV USA - Thursday, April 27, 2000 at 09:03:01 (PDT)
Dear Mike; Yesterday, writing to you, I had a minor epiphany, a slightly new way of seeing the matter and the kind of thing that sometimes happens when you keep going over and over the same point. Fill a space with litte 1/4" arrows, head to tail, go ing left to right. These represent a uniform freestream flow, a uniform field. Give to each arrow - vector - the value of 10, and to the total flow the summation of all the 10s in it. Place an object in the field immediately in front of one of the vector s. Our first approximation is that the object, or its surface, is subject to a force = 10. This is the assumption of classical [Newtonian] fluid mechanics. The total force, as when a free flow encounters an inclined plane, is assumed to be a succession of 10s. This is obviously not the case. The resultant by this method is far too little to account for measured values. The arrestation or deceleration of the vector immediately following bears on the first, those following on it. There is an accumulatio n or acrual of momentum, and it is that total, say 10 +9 +8 +7 and so forth, that bears on the surface, although, as already noted the progression is exponential. That's the field concept, with all the vectors affected by deceleration part of the POSITIV E DYNAMIC PRESSURE FIELD. +++ There is a corresponding NEGATIVE DYNAMIC PRESSURE FIELD on the downwind side. +++ Now that word DYNAMIC, and the distinction between static and dynamic pressures. Your vacuum is either in a container of some sort, or not, and if not it must be everywhere, as of a void, full of nothing, and no possiblility of anything leaking into it. Dynamic pressure is different. It occurs in a free atmosphere, one that, by definition, is not contained. Lift is the consequence of the function of dynamic pressures, positive and negative. This is evidently a difficult concept for the average individua l to grasp, and I continually find confusion on the point, most recently in the AOPA Pilot, Barry Schiff talking about the static pressures that sustain a wing. He is not answering my e-mails. This is the next big point, understanding that DYNAMIC PRESSUR E FIELDS are distinct from those that are static, and Ill leave it at that for the moment. Richard
Richard Miller <richardmilleratrocketmail dt com >
Santa Cruz, Ca USA - Tuesday, April 25, 2000 at 12:56:01 (PDT)
Dear Richard, Now that we have a defined "field", we need to know the very important concepts of vacuums, and low pressures. I define a vacuum as a space devoid of matter. Can a vacuum exist in our field? Is a low pressure a partial vacuum? Suppos e we reverse the flow in an "S" shaped sprinkler, put it into a swimming pool and hook it up to the skimmer, what direction would we expect our sprinkler to spin? If we created a vacuum where is it? If we created a low pressure where is that? Just how i s low pressure defined in our field?
Mike D. Genereaux <mdgenereaux>
Las Vegas, NV USA - Tuesday, April 25, 2000 at 08:27:16 (PDT)
Dear Mike, I was a little pressed for time when I wrote the previous entry and left it incomplete. The Newtonian/Mechanistic interpretation - that paragraph from von Karman I mentioned - is that the first fullback in line conveys his force, which is the primary force of the freestream flow, to the tackle dummy, then the next and the next and the next. This provices too little to do the job. In fact, part of the force of the second man in line, and a still smaller part of the third, fourth, and on to the last, i s being conveyed to the dummny through the contiguous bodies. Field is now defined, first as the uniform or mother field of a uniform flow (sort of like the yogurt, but dynamic) and the pressure field, all those elements of the orignal field that have, o r exert a pressure OTHER THAN that of the mother field. In other words, when any object impedes a flow the air backs up, it accumulates upwind of the obstructing surface. That's just too obvious for anyone to contest. All the backed up air, from the sur face (first fullback in the line) out to the margin, or periphery of the process, is, by definition, a pressure field, and all the elements in it, along a line parallel to the freesream flow, are contributing to the pressure exerted by the element in cont act with the surface. [The diminution in pressure along the line is ruled by the exponent - Vel-sq. - in the lift equation.] There, I've said it, yet again, about as simply as it can be put, but not really with much hope that anyone will understand what I'm talking about. R ichard
Richard Miller <richardmilleratrocketmail dt com >
Santa Cruz, Ca USA - Monday, April 24, 2000 at 14:39:04 (PDT)
Bill I am not here to argue with you on some nit-picking point. I'd like to say that your'e pages are exactly why the internet in unique. The choking-control of the dissemination of the sort of knowledge which is represented by western science is somewhat annulled by your pages. Yours is the first link on my site. Good on you...Good luck and keep this site up!!!! Regards, Loki Sorrenson TKF.
Loki Sorrenson <lokissonat1earth dt net >
USA - Saturday, April 22, 2000 at 22:08:13 (PDT)
Mike, Field, for current purposes, is defined as the continuous distribution of some quantity or quality. A big plate of yogurt would be a white color field. Some chocolate poured on it would represent the absense of that field, and another, with the darkness of the chocolate fading off into the original white. The quantity or quality in the atmosphere is DYNAMIC pressure, the force of molecules, if you want to conceptualize the air that way, on other contingents molecules. Imagine a line of fullbac ks, all in a row, hitting a tackle dummy. The first guy in line feels the great pressure, the full force of all those behind him. Subsequent bodies feel progressively less pressure. That's the way air stacks up, as wind, when it bears on a surface. Try that, see if you have any problems with it. Richard
Richard Miller <richardmilleratrocketmail dt com >
Santa Cruz, Ca USA - Saturday, April 22, 2000 at 17:00:03 (PDT)
Dear Richard, You claim that lift is a "field effect." I agree if our "field" is well defined. My perception of a field for the "field effect" is an atmosphere under pressure. One cannot hope to fly a balloon, airplane or hovercraft on the moon, because we do not ha ve a defined "field" to do so. How do you define "field" for the lift effect?
Mike D. Genereaux <mdgenereauxativillage dt com >
Las Vegas, NV USA - Saturday, April 22, 2000 at 10:29:19 (PDT)
Dear Mike, The matter is a little more complex than that, as most matters are. Book II of the Principia, you will find if you put your mind to it, is The Great Lost book. Few people read it or even refer to it, and that's because there is almost nothing of valu e in it. Followers of Newton derived, by inference, what they felt to be Sir Isaac's intent in the matter of fluid mechanics, which is what the book is supposed to be about. They made the assumption that a fluid made direct contact with an inclined surfa ce and derived the resultant force by means of trigonometric functions. These give a result too small by at least an order of magnitude, a fact discovered when practical tests were made in the following century. The interested parties should have gone b ack to the drawing board at that point and figured out that there was, is, no such direct contact. Lift is a field effect, as I've been saying for some time now, although without anyone paying the least attention. For a fuller exposition and a critical quote from vonKarman's book on Aerodynamics, go to GOOGLE dt com and type in Richard Miller Wings and run down the list till you find my Homepage. Sometimes it's at the top, sometimes second on the list, sometimes furt her down. What we typically get, Mike, when we begin, with common sources, is a very slipshod and superficial explanation of the facts. It is necessary to dig into original sources, and do a good deal of thinking for onself to get anywhere neat the - exc use the expression - truth.
Richard Miller <richardmilleratrocketmail dt com >
Santa Cruz, Ca USA - Wednesday, April 19, 2000 at 15:00:28 (PDT)
Dear Richard, I know you are up on Newton, did you know that he claimed he had mathematical proof that heavier than air flying machines are impossible? Aparently apples fly, birds do not? Mike
Mike D. Genereaux <mdgenereaux>
Las Vegas, NV USA - Saturday, April 15, 2000 at 07:47:17 (PDT)
nice site but you dont go into much technical detail. dont you know much, or what? look if you want ,well a more technical hand send me an email, ok.
steve hope <steveathotmail dt com >
leeds, uk - Wednesday, April 12, 2000 at 06:56:31 (PDT)
regarding panthony's bit about 'a comin or a goin' on black holes and big bang effects. it might be illuminating to note that although objects do get attracted to black holes at ever increasing rates(owing to newton's gravitation, not einstein's), for an outside observer, this process takes a very long time (in fact, infinitely long as time is dilated). to the person falling into the hole, it takes no more time than is 'usual'. this may be of use in consideration of the 'a comin or goin' business... mike gleeson
mike gleeson <djmikegleesonatcrapmail dt com >
sydney, AUS - Thursday, April 06, 2000 at 21:55:34 (PDT)
I have a question for the experts. There are six simple machines, the axle, lever, pulley, screw, wedge, and wheel. None of these machines produce a force, rather they change and manipulate the force applied to them. Why then do engineers define a t ool (a wing) and claim that this mere tool produces a force called lift? I don't understand.
Mike D Genereaux <mdgenereauxativillage dt com >
Las Vegas, NV USA - Wednesday, April 05, 2000 at 08:57:25 (PDT)
WARNING WARNING WARNING I mentioned earlier that one could put a wing on a plane with the trailing edge as the leading edge. Though I believe the plane will still fly I also believe the plane will be highly unstable without fly by wire equipment. Ple ase do not try this on a real airplane. Consult with trained experts. You will be seriously injured or killed if you try this. I accept no liability for injuries or death.
Mike D Genereaux <mdgenereauxativillage dt com >
Las Vegas, NV USA - Tuesday, April 04, 2000 at 02:43:34 (PDT)
Dear Mike: That's a healthy attitude you have, checking up on the things you know, or think you know. I'm going to undertake to help you, and I'm going to try to keep your attitude in mind. You mention Bernoulli with regard to Newton's Laws. That d oes not seem appropriate, and here's why. Newton devoted the second book of his Principia to the subject of fluid mechanics, the first having covered the actions and the reactions of solids. Those three laws. He did not, however, grasp the essential diffe rence between the two sciences. Bernoulli stated the basic, or First Law of Fluid Dynamics, the one that states the reciprocal nature of pressure and velocity. It is ironic that the majority, if not all the theoreticians, when they set about to explicate the process of lift, turn to those eponymous laws, the Great Three, without the realization of their irrelevance to the subject. Yes, within the Bernoulli formulation there are actions and reactions; they act as a kind of subset to the fluid dynamics. The key in all this, what Newton did not grasp, is the concept of the field, that there is no DIRECT TRANSMISSION of force in fluid phenomena. That for starters.
Richard Miller <richardmilleratrocketmail dt com >
Santa Cruz, Ca USA - Monday, April 03, 2000 at 17:56:46 (PDT)
Newton wrote 3 laws. The first being once at rest remains at rest. Once in motion remains in motion. Inertia, resistance to change. It is a statement about matter being in a position. Rest or motion. The second law is force equals mass times acceleration. If acceleration is equal to zero then our force is also equal to zero. The second law says that force and acceleration are exactly the same thing you cannot have one without the other. When it comes to Bernoullis Principle, according to Newton, to change from one pressure to another a force will be required. An example of a first law motion, is an orbit. The moon has been in orbit for billions of years. First law motions do not have a reaction to them. Isaac Newtions, greatly misunderstood, third law says that for every action there is an equal and opposite reaction. It would be better said, for every force there is an acceleration. Upwash and downwash are first law motions, therefore they do contribute to lift. I always worry about what I do know because there are always mistakes in it. But I really like experiments. Nature talks to me.
Mike D. Genereaux <mdgenereauxativillage dt com >
Las Vegas, NV USA - Sunday, April 02, 2000 at 22:25:04 (PDT)
In Alistair B. Fraser Bad Meteorology it was mentioned that" the cap cloud(on Mt Rainer), when the wind (coming from the right) blew against the sloping side of the mountain and was forced up."

But why did the cloud form? To quote:

"If that explanation is not simple enough for your students, just present the facts: when the temperature drops below the dew-point temperature, there is a net condensation and a cloud forms." This explanation is incomplete and ignores that the fact that the "Dew Point" in a volume of air is also dependant upon pressure. As in the case of the summit cloud on Mt. Rainer...these are caused by the due point being reached due to the reduction of air pressure as the wind blows over the summit (Bernoullis Principle). Notice the cloud only over the summit not in air at the same temperature(elevation).

It is all well and good to offer a 1 dimensional explanation; but in a gas there are actually 3 dimensions that are required to explain the phenomena. Atmospheric science is not trivial.
Hartmut von Gaza <hvgathvgsys dt com >
Ed, Ab Canada - Saturday, April 01, 2000 at 16:36:13 (PST)


A thrust is a loss in mass with a gain in momentum. Since air passes a wing, the wing never gains a mass nor does it lose a mass therefore it (the wing) does not produce a thrust. Neither do propellers because propellers are also wings. Most of the kinetic energy from a rocket is wasted because thrust is only achieved at the moment when mass is lost. I consider aerodynamic flight when an object is suspended and supported by its atmosphere. I consider a floating boat to be ideal flight, because it displaces its mass, with the mass of the of the water without any loss of kenitic energy. The key word for airplane flight is displacement. The wings displaces the mass of air equal to the mass of the plane. If it displaces more mass than the mass of t he plane, the plane risses. When we take a finite quantity of air particle in a streamline and accelerate that streamline by changing its course the average distance between the particles increases, this causes low pressure. If areodynamic flight is def ined as an object that is suspened and supported by its atmosphere, then I and everybody can suspend and support an object in an atmosphere regardless of its shape or angle of attack. All you gotta do is accelerate the fluid above the object with a until it flies. Airplane flight is the mechanical version of maniplating buoyancy.
Mike D Genereaux <mdgenereauxativillage dt com >
Las Vegas, NV USA - Thursday, March 30, 2000 at 12:16:03 (PST)
My daughter won 2nd Place Honorable Mention for her 7th grade Science Fair with one of your experiments, Electrostatic Motor. My husband and I worked diligently on this with her but the instructions were a little unclear but due to the lateness of tim e we submitted the project inoperable. I don't know what could have gone wrong but she won anyway. We used a black&white 17inch television set as the power source, 3 2-liter bottles, rod, metal cap, stiff wire, caulking and we couldn't ground it because we have wood floors. Unfortunately, it didn't work in the school which has concrete floors. We can't imagine what may have been the trouble but thanks anyway.
Sylvia Kearney <bishopjbkataol dt com >
East Orange, NJ USA - Tuesday, March 28, 2000 at 20:40:46 (PST)
I consider flight when an object is suspened and supported by its atmosphere. Birds, planes, hot air balloons, pollen, dust, people cars and houses during hurricanes and tornadoes all fly. How to areodynamicist explain human flight during a tornadoe, when humans do not have wings? Is uncontrolled flight not flight? Bull. Wings are not necessary for flight. Wings are merely a tool used to control flight. Wings are not the only tool that can.
Mike D Genereaux <mdgenereauxativillage dt com >
Las Vegas, NV USA - Tuesday, March 28, 2000 at 08:41:37 (PST)
Thanks for your topic on the make-your-own maglev. I am trying to build a levitating car for a science projects but all of my ideas failed. I'm going to try your idea and i'm sure it will work. Thanks a lot, you're a life saver!!!
Matt <Spudin8rataol dt com >
Gig Harbor, wa USA - Sunday, March 26, 2000 at 16:08:35 (PST)
I can get an airplane to fly with a negative angle of attack. Take a plane with a NACA6316 or similar flat bottom curved top wing. Take the trailing edge and make that your leading edge. Put it back on the plane and fly it level. Lift is caused by a positive accelerating fluid flow on top of the wing and a zero or negative accelerating fluid flow under the wing, in an atmosphere that is under pressure. A wing is a tool that controls the magnitude of the accelerating fluid about a wing. A wing, like all tools, do not produce forces. It transfers a force to the air and as a response the atmosphere will support the plane.
Mike D Genereaux <mdgenereauxativillage dt com >
Las Vegas, NV USA - Saturday, March 25, 2000 at 21:41:31 (PST)
your,site is impresive and is appering to make an impact sombody should sue the school system for it's ignorance being an idiot is ok but not even trying to aviod it is shamful
et <splmflyatjps dt net >
USA - Thursday, March 23, 2000 at 18:06:35 (PST)
this page really helped me out with a report thatnks alot
john
warwick, ri USA - Wednesday, March 22, 2000 at 12:33:11 (PST)
i am currently doing a research project for high school on mag-lev trains for my ap physics class, could you send information on then to me, thank you very much.
jake vanderhom <rednekcsa1ataol dt com >
memphis, tn USA - Tuesday, March 21, 2000 at 09:46:02 (PST)
Your page was good, but it was really hard to understand what you were writing. I suppose I've been misleading myself for too long. Keep up the wonderful work!
Carmen Hallis Green <-->
USA - Saturday, March 18, 2000 at 19:09:44 (PST)
I whish that you folks would stop messing around, and actually produce something. What I mean is, stop talking, like that JerryDeckeratKeelynet dt com . He is so full of it, I can't even think. what a liar he is, not to mention that he likes boys! He l ikes young boys, I hear; around 16!!
Jim Parker <90876atnu_energy.com>
Rumney, NH USA - Friday, March 17, 2000 at 21:48:35 (PST)
Does electricity flow better thorough a battery or lemon? Please answer.
Stefan
USA - Thursday, March 16, 2000 at 15:10:29 (PST)
Does electricity flow better thorough a battery or lemon?
Stefan
USA - Thursday, March 16, 2000 at 15:08:24 (PST)
Two textbook misconceptions: 1)arterial blood always seen as red and venal blood as blue on charts, thus teachers and students perpetuate the misconception that "blood is blue till it hits oxygen." 2)exaggerated ellipse representing earth's orbit (a perspective drawing in nearly every textbook I've ever seen) perpetuates the misconception that the orbit is a very long thin oval, with an eccentricity close to 1.
Kathy B
WI USA - Thursday, March 02, 2000 at 18:09:41 (PST)
At first, congrats to your excellent explanations. I wonder about just one thing: Who ever came up with that definition that electrical energy is transported through the electric and magnetic fields? [J.C MAXWELL, I THINK -billb] I know this is usually ported by the technicians and when I was at engineer's school my teachers tought me the same. But I'd rather say it in another way: energy flow _can_ be described by electromegnetic fields but _also_ it is valid to say that energy flow is expressed by voltage and current. (energy flow per second = Watts = V times I) Both expressions are equivalent as voltage forms an electric field and vice versa, and current in a wire forms a magnetic field around that wire. But in my opinion it is not valid to claim that energy is _only_ carried by the fields. Instead say: voltage, current and the fields act together as the energy carrier, or even better: the "charge" (=matter) expression of electricity is interchangible with the "fields" expression. (sorry if this is bad english) (To the people now thinking of radiating energy with an antenna: here the antenna acts as the conductor and carries the flowing charge - well, flowing forth end back. And thus form the electromagnetic field that travels out into space. The receiver antenna also becomes a part of this "circuit" [in fact it is more like the field of one wire induces a voltage in a parallel wire])

Also I found a somewhat erraneous sentence:

"Electric energy is very similar to radio waves, but it is very low in frequency." This is a very misleading sentence, in fact can lead to wrong conclusions. What you wanted to say is: The mode of energy transfer to the power outlet and by radio waves is basically the same, except the frequencies are different. [despite the difference in the amount of power that is usually received] This is not so wrong, is it? Greetings, M.
[I'VE ADDED THIS TO THE F.A.Q] Markus Petz <markus.petzatkfunigraz.ac.at>
Graz, AT Austria - Saturday, February 19, 2000 at 17:08:44 (PST)


Isn't the biggest misconception that we should ACTUALLY thank Nikola Tesla INSTEAD of Benjamin Franklin for discovering electricity!!!!!!!!!!!!!!!!
Dana Culic <daculicatindiana dt edu >
USA - Monday, February 14, 2000 at 09:48:32 (PST)
Static electricity can pick up dust, hair, & plastic. No amount of regular electricity from a wall socket or a car battery can. I say they are different on a molecular level & schools have been missing this fact for decades. I believe gravity is directly related to the ability of static electricity to pull non-magnetic objects, and likewise anti-gravity will be directly related to the ability of static electricity to push non-magnetic objects. Paul Scherffius schrffsatprodigy dt net
paul scherffius <schrffsatprodigy dt net >
holiday, fl USA - Thursday, February 10, 2000 at 20:08:10 (PST)
From the above: Static electricity can pick up dust, hair, & plastic. No amount of regular electricity from a wall socket or a car battery can. Not true, since I have a 30,000 volt DC power supply right here which picks up lint and attracts plastic. In other words, STATIC ELECTRICITY means the same as HIGH VOLTAGE. (And when static electricity flows, it can still pick up lint, even though it's no longer static electricity!) A car battery cannot pick up lint because it only provides 12 volts, and it needs to be at least several thousand volts. I tried this (hazardous) experiment: connect about sixty 9v batteries in series to obtain almost 500 volts. (Warning: this can easily electrocute you!) Hang a small sheet of charged plastic between two metal clipleads spaced about 1cm apart. When the other ends of the clipleads are touched to the battery terminals, the plastic moves slightly! The 500 volts is just barely enough act like "static electricity." With a 5,000 volt power supply, the attract/repel forces become much stronger. A physicist would say "in the everyday world, electric forces noticably move objects only when the fields are strong than approximately 1,000v/cm"
Bill Beaty <>
Seattle, WA USA - Sunday, February 20, 2000 at 09:48:20 (PST)
After reading the erudite comments of 'Dragon Boy Eddy', it looks as though textbook misconceptions may be gaining the upper hand and it bodes ill for the rest of us if he represents the type of individual leaving the educational system these days! Le t's pray that 'Eddy' is the exception!!! Good luck with your crusade!!!
L A Waygood <adrian.waygoodathct.ac.ae>
Abu Dhabi, UAE - Wednesday, February 09, 2000 at 02:22:23 (PST)
I failed to notice anyone who questions the "Big Bang Theory". First, my comment(s): If matter cannot move faster than light, how did the entire contents of the universe escape from the "Gran'daddy" of ALL black holes? As for the theory that matter can exceed the speed of light for a short distance, (seemingly for the purpose of supporting this theory) is there any proof? If all matter was created in one event, or explosion, why do some of our planets revolve on their axis one way, some the other? (Is this conservation of angular momentum?)
oldmobie <oldmobieathotmail dt com >
USA - Thursday, February 03, 2000 at 17:57:31 (PST)
Being a victim myself of previous, erroneous science regarding environmental toxins, I suggest visiting my website for a truer cause of the immune epidemics. The numbers of chemically injured, unsuspecting citizens are growing at frightening numbers. Government, medical systems and media ironically never mention these details. Allene R. Wahl, Ph.D., C.N.C. Int'l. Resource Center for Chemically Induced Immune Disorders Ph. (847) 678-5934 FAX: (781) 240-2404 e-mail: allenewatjuno dt com Website: http://members.tripod dt com /immune_disorders/index.html
Allene Wahl, PhD <allenewatjuno.com>
Chicago, IL USA - Tuesday, February 01, 2000 at 16:47:40 (PST)
We are engaged in a study of "electricity" and are using PASCO Scientific sensors with an interface linked to our computers to measure the voltage of various "fruit batteries". My ongoing concern has been that we conduct our experiments correctly and do not teach "bad science" Your site was enlightening. Can students email questions to you? We will be presenting our results at the NYSC&TE COnference in March. We are also presenting at the M/SET Conference in San Diego this weekend. After reading information posted at your site, I will again review and edit any notes that I have written. Any advice is welcome. Thanks, Lori
Lori <lori_grasselliatfc1.nycenet dt edu >
New York, NY USA - Monday, January 31, 2000 at 05:56:28 (PST)
You state: "I hope that very few students will attempt to perform the color recombination experiment depicted in their books, for disappointment awaits. " I hope the exact opposite. I want people to attempt to validate experiments. Science requires a rigorous thought process. Simply taking something on blind faith defeats the purpose behind the science. Of course this would require that the instructor b e able to explain why the experiment failed and illustrate how the book is wrong. I am making the fundamental assumption that your assertion is correct (that it takes three prisms to recombine the color.) Obviously that assertion requires validation. Regards, Dan
Dan Maslowski
Den Haag, The netherlands - Friday, January 28, 2000 at 02:41:22 (PST)
I wouldn't say "an atom is made of particles of charge", since charge is a PROPERTY as those definitions you mention say. If you say so it's like saying "a red balloon is made of red".
Student
Mexico - Tuesday, January 25, 2000 at 11:40:58 (PST)
Referring to the above... yes, charge is a property, but it is more than that. It is like mass: it is a CONSERVED QUANTITY. Whenever charge goes missing from one place, it MUST have moved elsewhere. This is very different behavior than something like "red" which is purely a property and is not a conserved quantity. We can have a flow of matter, and we can have a flow of charge. Do particles of mass (of matter) exist? Yes, and so do particles of charge, although obviously those particles are not ONLY charge and nothing else. Another way to say it: the entity "charge" is made from particles, just as the entity "matter" is made from particles. It is a misconception that charge is nothing but a property. Instead, charge is substance-like.
Bill Beaty
Seattle, WA, USA - Tuesday, January 25, 2000
Dear Idiot, I am a final year electronic engineering student and would just like to say: YOU ARE A COMPLETE AND UTTER GIMP!!!! Your 'misconceptions' are a pile of crap - a high school physics student could tear your arguments to threads. 'In AC ccts the charges wiggle back and forth', 'In an AC system the electricity...sits inside the wires and vibrates','In a simple electric cct, ...no electricity is ever gained or lost','light bulbs destroy electrical energy' What a pile of steaming shit!!!

Please don't propagate your dumbass genes, (That means don't have any kids idiot!), Dragon Boy Eddy
Dragon Boy Eddy <mdonohoeatnetsoc.ucd.ie>
Dublin, Ireland - Tuesday, January 25, 2000 at 11:00:06 (PST)


I've invited the above person to defend his assertions on a civilized forum (PHYS-L). My, but "misconceptions" can trigger emotions, no? It's like religion or politics: some concepts threaten our most deeply-held beliefs. When this happens, it is essential to maintain respect for one's opponent.
Bill Beaty
Seattle, WA, USA - Tuesday, January 25, 2000
I really like the principle behind this site. Wouldn't it be great if we could have a worldwide clean-up of all of those text books to weed out the myths and susperstitions that have crept into them over time?
Dr. Gareth Davies <dr_gareth_daviesatyahoo dt com >
London, UK - Wednesday, January 19, 2000 at 05:34:11 (PST)
HOMINIDS DID NOT EVOLVE UPRIGHT WALKING TO FREE THE HANDS FOR TOOL USE.
Most K-12 textbooks ignore the purpose of bipedalism or present some way-off-the-mark theory that had long ago been cast into the scientific trashcan. The above hypothesis that we stood up to use stone tools (supposedly to scare off predators and eek out a living on the savannah) is fairly sound except that there are no known stone tools or tools of any kind older than 2.5 million years ago. Furthermore, there is no evidence that either Ardipithecus ramidus or Australopithecus anamensis used tools.

WE DID NOT BECOME BIPEDAL BECAUSE THE THINNING FORESTS FORCED US OUT ONTO THE SAVANNA
This is false because in fairly open terrain, where the maximum possible speed is much greater than that in forested regions, the evolutionary advantage would go to the swiftest, not to the most energy-efficient. That is why partially bipedal primates are more numerous in woodlands than on prairies or grasslands. Also, while a bipedally-adapted creature might be more efficient on two legs, a quadruped will actually be less efficient. Evolution is only concerned with the present, which means that our distant ancestor would not have been interested in standing up in order to benefit his great-great-great-great-great-great-great-great grandchildren.


Mary Craig <viner2012atnetzero dt net >
Belmont, MA USA - Saturday, January 15, 2000 at 12:42:02 (PST)


Ice Friction, skates, and melting I read the section on ice skates not running on a thin layer of water. I've often wondered about this theory and it seems that it would not be difficult to test..... But anyway.

I do find one fault in the explanation given in the linked e-mail and again in BAD CHEMISTRY. The authors state that the ice skate rides on an area of about 11 cm by 3-4 mm. That would be the total length of the blade. The ice skate is curved (that's how you can turn it) and the contact area between the blade and the ice is much smaller. If we make the wild assumption that the actual contact area is 2 cm long by 3 mm wide, that gives an area or .6 cm^2 and a resulting pressure (80 kg skater) of 133 atm. That would raise the melting point of the ice a little over 1 degree C.

That's still not enough to provide a pressure melted area for the skate to slide on unless the ice is at -1 C. But the how about the friction from such a large pressure! That energy has to go somewhere.... How about into melting ice?

Iceman! <cadkathotmail dt com >
Silicon Valley, CA USA - Wednesday, January 12, 2000 at 10:37:11 (PST)


me dont like your site
egtsbryn
USA - Tuesday, January 11, 2000 at 10:05:45 (PST)

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