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Comment Book Archive, year 2001

K-6 Science Misconceptions Page

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Antigravitational, i.e. gravifugal flying craft is a scientifical project. I believe this project will be a general base of the future MATURE human civilisation, which will float in atmosphere and in space sorraunding planet Earth. Since, unfortunately, nobody likes scientifical projects, gravifugal flying craft is unknown. I asc any help to promote this project. Linking... Larger information at the site:http://www.geocities dt com /agravity/ANTIGRAVITY.htm Thank you very much, Prof. Petar Bosnic Petrus
petar bosnic petrus <petar.bosnicatinet.hr>
samobor, ?upa Croatia - Friday, December 28, 2001 at 08:41:15 (PST)

ost of the things you find errors with are just simplified models. These models were created so that we can conceptualise the scientific principals. The creators of the models are not saying; "This is what's happening." They are saying "What is happening is _like_ this." I think that when it comes to scientific issues at an atomic and subatomic level (such as behaviour of light and electricity) we are looking into a world that is utterly foreign to us to a degree that we simply do not have anything to compare it too. It really is too strange in comparison to our everyday perceptions.
liam k.
USA - Monday, December 24, 2001 at 00:59:57 (PST)
NO, IN THE EVERYDAY WORLD, GASES DO NOT EXPAND TO FILL THEIR CONTAINERS In regards to your text associated with the title above: Please address what would happen if a gas of approximately the same density as air were injected into a container of air. Maybe Nitrogen would be a good example for this, or perhaps describing the mixing of the same gas of different temperatures. A simple experiment that anyone can perform with two people and a stop watch. Determine how fast and in what directions flatulence spreads in a room with minimal air currents. Air currents could be checked with smoke of some kind. This is kind of gross but I think it gets the point across. Are you sure that you are explaining misconceptions or just pointing out poor choices of vocabulary? In other words, I think you are trying to be very precise with word usage. For example In relation to gas: The word "expand" could be synonymous with the words "spread" and "mixing". Thank you for reading, A. Robert Whitman
A. Robert Whitman <kaerob1atattbi dt com >
Portland, OOR USA - Saturday, December 22, 2001 at 02:40:39 (PST)
where can i find a table of the amount of electricity my home appliances use?
maggie <mmcclellatroosevelt dt edu >
crystal lake, IL USA - Thursday, December 20, 2001 at 06:37:38 (PST)
You wrote: In a simple electric circuit, the electricity flows in a circle, while the energy flows from the source to the load. The energy does not follow the flow of electricity; electricity and energy are two different things. No electricity is gained or lost as it circulates within the wires, yet batteries create electrical energy from chemical energy, and light bulbs destroy the electrical energy as they convert it into light. Electrical energy is a one-way flow from battery to bulb Comment: In the above paragraph, you say that the energy batteries create electrical energy from chemical energy. I would refrain from the term creating since the process is you mean is really conversion. More paradoxically, the paragraph says that that the energy is created in the battery and "destroyed" in the bulb while simultaneously stating that it was converted to light. Was it detroyed or converted? Unfortunately, these kinds of terminology are the things that cause confusion. If you use the idea of creation and destruction as meaning conversion into and conversion out of the phenomenological domain, then that has to also be made explicit to the reader. The ideas are sufficient confusion. However, compounding that confusion with an idiomatic vehicle makes it impossible for the reader to decipher. One day I would like to write a physic book that would be extremely procedural, and rigourous. It doesn't have to be dry to get the point across, just thorough. Also, I have made every type of physics error that there is to make. Wilfredo Colon PS I will write more once I have had a chance to review more.
Wilfredo Colon <colonateng.usf dt edu >
Tampa, FL USA - Friday, December 14, 2001 at 09:43:03 (PST)
What are electricity's components?
sumbody... <dunno>
Plano, TX USA - Wednesday, December 05, 2001 at 16:20:34 (PST)
I would like you to put this question up. Who was the first to use electricity, and when. thanks
Fernando <explozaoathotmail dt com >
wblomfield, ma USA - Wednesday, December 05, 2001 at 12:36:49 (PST)
I love this site! Before our (Science Teachers at my school)"battle of the Text Book" was finally ended, I would have students refer to this site to help them identify the misconceptions printed (Prentice Hall Series). Thank God we have a terrific principal that faught with us to get better texts for REFERANCE! Thank you a great deal.
Sherry Mitchell <Equus04ataol dt com >
Northford, CT USA - Monday, December 03, 2001 at 15:19:22 (PST)
Help me please i know nothing about remote control im a young teen and need it for a robot im building how can i learn before im much older please help!
Slash <heavenly3atklis dt com >
NA, NA Canada - Monday, December 03, 2001 at 14:03:36 (PST)
Wow... I would've avoided so much confusion in physics and EE classes had the textbooks explained things your way. I always thought "static electricity" was some kind of oxymoron, but I could never win people over to my cause. Great website!
PA USA - Thursday, November 01, 2001 at 11:59:40 (PST)
b>your idea really sucks :)
jan and amber <hunniebun55athotmail dt com >
USA - Monday, October 22, 2001 at 11:14:40 (PDT)
I would like to know what are ballons made up of and what kind of air pressure one of my expierments need it's the expierment where you put a straw on a balloon and put string though the straw and see how far the balloon will go?
Eric <ViperfreakGTataol dt com >
USA - Sunday, October 21, 2001 at 16:30:07 (PDT)
Hi from Canada!
Mila Jackson <mila.maxatsympatico.ca>
Toronto, ON Canada - Wednesday, October 17, 2001 at 11:51:49 (PDT)
You will be hearing from me soon. Thanks
Milton Lewis <
kdlatfastransit dt net >
Lake Charles, MI USA - Tuesday, October 16, 2001 at 22:06:51 (PDT)
Good web with cool info. Thanks.
Everd Linten <elin345ataol dt com >
Henderson, KY USA - Tuesday, October 16, 2001 at 19:07:36 (PDT)
Good job! Thanks!
Gary Shafer <jdb183atradar dt com >
Naches, NY USA - Tuesday, October 16, 2001 at 16:41:14 (PDT)
Can anyone tell me what to use as a conductor so i can tell how high the electric fields are in a thunderstorm???I have a Voltmeter and cable but thats all at the moment.
Jamie <spongesurferathotmail dt com >
sandown, hampshire, isle of wight U.K - Sunday, October 14, 2001 at 01:02:00 (PDT)
I found your site very interesting. Thanks!
American Engineering <robertwillyatyahoo dt com >
Salem, USA - Thursday, October 04, 2001 at 18:12:53 (PDT)
love this site
tony [SPAMMER PORNO LINK REMOVED] <tonyfranatwebtv dt net >
San Clemente, CA USA - Thursday, October 04, 2001 at 16:45:45 (PDT)
Can you tell me if electricity has weight?
Peggy <mcavalloatchsd.k12.pa.us>
Patton, , PA USA - Thursday, October 04, 2001 at 08:47:12 (PDT)
i have some questions to ask: When high voltage power is transmitted to towns and cities it first goes to a terminal and then a substation. What is the purpose of the substation? What are the most important things found in a meter box and why are they important? When acting together, some chemicals produce electricity. what are some examples? if anyone knows the answers to these questions (they are for a school assignment) could you please email the answers to me. thanks very much ~KARLIE~
~KARLIE~ <bee_visathotmail.com>
Perth, WA Australia - Friday, September 21, 2001 at 13:48:52 (PDT)
I have a question for you concerning electrical plugs. Why are there holes in the end of the plug? And are the holes the same distance from the insulated end of the plug. Do you know?
Jay <jayatcaceng dt com >
USA - Monday, September 10, 2001 at 10:42:28 (PDT)
For hundreds of years it was thought that a rock always falls faster than a feather, come to find out the experiment was contaminated by the atmosphere. In many college level physics text books it is thought that two pieces of paper will come together when faster moving air is blown between them. Contaminated experiments can fool a lot of people, huh?
Mike Genereaux <mdgenereauxativillage dt com >
Las Vegas, NV USA - Monday, September 10, 2001 at 08:07:59 (PDT)
Liked the site. Thanks!
Felicia Boutin <tex2309atcfl.rr.com>
Toronto, ON Canada - Thursday, September 06, 2001 at 14:07:20 (PDT)
i just red sum ov da utha comentz u guyz write in ere, god, CHILL! think, u have your whole life ahead of ya, even if u r way into ya 40s! science isnt everythin ya know, (well it iz really, haha!) luv ya loadz from the peeps in wales luv Ree X
Ree (again)
USA - Thursday, September 06, 2001 at 10:47:37 (PDT)
your site is... neva mind! im trying to do homework on metals, this is the best that came up on "ask jeeves", im miffed, and also bored of homework and assignments! the luvlee peepz from wales (where i live) say hi to America, i wanna c more Welsh peep z on comment bookz and stuff! Ok, im bored,and easily distracted... OOOH! A BUTTERFLY!.... sorry, im back! Luv all u science peeps, i have a personal grudge against science, it appears to return that thought. good luck rebuildin ya site and stuff, k? Luv Ree x
Ree <not tellin ya, HA HA!>
Wales, uk - Thursday, September 06, 2001 at 10:42:54 (PDT)
Is it possible to generate serious electrical power using a concentration cell? Such as the dilution of a large volume of salt water with fresh water - using the sun to concentrate by evaporation. And is anyone doing it or experimenting with it? This s eems to me to be a practical means of producing solar energy at a competitive cost?
keith rex <biochemrexatnetscape dt net >
Sydney, NNSW Australia - Wednesday, September 05, 2001 at 23:11:28 (PDT)
Splendid web page! I have another theory to add to your collection that was offered to me in my 11th grade physics class: When I asked the question, "Why or how does ice float?", my teacher replied,"Well, we all know C. that ice floats so that the fis hies can live during the winter." Everyone laughed at how stupid I was of course.
c. Castronovo
OR USA - Tuesday, September 04, 2001 at 11:11:41 (PDT)
Hi from france !
trance mp3
France - Saturday, September 01, 2001 at 02:42:17 (PDT)
I would like to see 'rectified' the reletionship betwwen your red/green gel sub-particle explanation with..the revelation using transformers, of what a 'magnetic circuit-A-fields' science RELLY IS! I am imagining a demonstration using thick gels on a c ookie sheet,filled with small round white beads; where motions of the gels would interact with the spacing(waves?) of the white beads(WHICH ARE THE 'AETHER') Yes,I believe in the either and that it's understanding IS the new science. (In my anology, the a reas of cookie sheet visable as the either moves would have to be the illusive "nothing".good stuff..) C.B.
Robert Bertok
USA - Friday, August 31, 2001 at 17:25:27 (PDT)
Great site! Thanks!
Rosa Alex <rosa.alexatcanada.com>
USA - Thursday, August 30, 2001 at 09:11:55 (PDT)
Informative site - just this nitpicking comment: your explanation of water vapour states that fog is a liquid. It is a suspension of a liquid in a gas.
Bill Logan <james_bombedathotmail dt com >
USA - Monday, August 20, 2001 at 01:04:29 (PDT)
Now I perfectly understand why I was a hitting a block always in my high school as far as physics was concerned.I had sailed through most of the chapters till I hit on electricity.That killed it, for the other kids were just memorising the stuff and so I felt I really din;t understand a thing.It is really amazing to see how textbooks in India also carries the same misconceptions as here.I wonder is the phenomena true worldwide? I can at least see much similarity in the way electricity is explained in the physics book in my country and the k-6 books out here in USA.
Abhishek Lahiri <abis1234athotmail dt com >
san jose, ca USA - Saturday, August 18, 2001 at 13:45:44 (PDT)
I must say that I find your papers very interesting. I have been a student of Physics and related subjects for most of my life. One of my favorite sciences is the principles of statistics. Data can be percieved in many ways, most of them different, but still share a common truth. This is much how I view your approach to the explanation of your topics. In general I have not read anything you have written that I would strongly contest. I would hope that everyone that reads your work should be inclined to reaserch the subjects and determine if your concepts are accurate. I have learned much as a result of reading your work and would like to offer my sincere thanks for your no bull approach.
Robert Cox <biaxidentatnetzero dt net >
Evansville, IN USA - Wednesday, August 15, 2001 at 21:13:01 (PDT)
Nice site...
fonts <hgkcfocatcyberbabies dt com >
USA - Wednesday, August 15, 2001 at 14:38:05 (PDT)
I commend your effort, even though I do not agree with all your corrections. A science model should be sufficiently self consistent and consistent with observations and experimental results. But I am afraid that even some professional scientists, in "c utting edge" science have serious misconceptions (in this sense). For example one of the strange myths is that the speed of light relative to a moving object is constant and isotropic. This is not what Special Relativity says, does not agree with mathemat ics, does not agree with experiments and observations. And as far as I know even these scientists treat the velocity of light as a vector in their calculations. It is an amazing example of "the emperor's new clothes" (H. C. Anderson). So it is a good thin g to teach students to be critical, to check for themselves when feasible, and not to swallow everything they read in textbooks. As regards the airplane: consider angular momentum, energy and the position of the centers of mass (plane, air, earth etc. as well). And note that the plane is pressed up, not sucked up (the air above actually presses it down!)!
Percy N. Kruythoff <Percy.Kathome.nl>
The Netherlands - Monday, August 13, 2001 at 06:07:25 (PDT)
Slash again please i must know the ansewer to my qustion my email will work now
slash <heavenly3atklis dt com >
Canada - Wednesday, August 08, 2001 at 07:15:32 (PDT)
please tell me must wire be atracted by magnets to be used in a electric generator. P.S PLEASE I MUST KNOW!
Slash <?>
Na, an USA - Tuesday, August 07, 2001 at 14:09:43 (PDT)
Whenever I want or need a bernoulli effect I always have to use Newtons second law of motion F=ma to achieve it. So I do not understand the controversy of Bernoulli vs Newton with respect to airplane flight. I have found that the more of Bernoulli's principle is used the graeter the lift per watt. The less Bernoulli's principle the greater the power per lift. I would want to think that flying machines efficiency should be rated by its lift per watt. What I find in text books is the effiency is rat ed by its lift to drag ratio. Isn't drag a nuisance, anyway? If you fly slow then drag is low. So overcoming drag should only be a high speed problem, right? Buoyancy can ultimately be traced back to Newtons second law of motion. So all things fly by F=ma. Unfortunately that does not always lead to understanding. If I stretch a streamsheet over a one ton object, and the sheet is stretched until a perfect vacuum is formed and then I lift the sheet upwards will the object follow? Would I be lifting a vacuum or a one ton object? I can demenstrate stretching a streamsheet and lifting objects with it. The low pressure on top of a wing must be rising for the airplane to rise. It turns out to be much more complex than I ever imagined.
Mike Genereaux <mdgenereauxativillage dt com >
Las Vegas, NV USA - Saturday, July 28, 2001 at 10:03:34 (PDT)
i have some questions to ask: When high voltage power is transmitted to towns and cities it first goes to a terminal and then a substation. What is the purpose of the substation? What are the most important things found in a meter box and why are they important? When acting together, some chemicals produce electricity. what are some examples? if anyone knows the answers to these questions (they are for a school assignment) could you please email the answers to me. thanks very much ~KARLIE~
~KARLIE~ <bee_visathotmail dt com >
Peth, WA Australia - Friday, July 27, 2001 at 19:44:05 (PDT)
I have really enjoyed reading the site, which I stumbled upon while doing research for a "Teaching High School Science" course. I think much of my difficulties in teaching electricty units stems from the fact I have many conflicting conceptions of key concepts. Thanks also for your suggestions for vocabulary use to prevent vernacular misconceptions. Thanks!
Emily Gesner <ekgesnerathotmail dt com >
Toronto, ON Canada - Monday, July 23, 2001 at 12:26:51 (PDT)
I have really enjoyed reading the site, which I stumbled upon while doing research for a "Teaching High School Science" course. I think much of my difficulties in teaching electricty units stems from the fact I have many conflicting conceptions of key concepts. Thanks also for your suggestions for vocabulary use to prevent vernacular misconceptions. Thanks!
Emily Gesner <ekgesnerathotmail dt com >
Toronto, ON Canada - Monday, July 23, 2001 at 12:26:00 (PDT)
I have really enjoyed reading the site, which I stumbled upon while doing research for a "Teaching High School Science" course. I think much of my difficulties in teaching electricty units stems from the fact I have many conflicting conceptions of key concepts. Thanks also for your suggestions for vocabulary use to prevent vernacular misconceptions. Thanks!
Emily Gesner <ekgesnerathotmail dt com >
Toronto, ON Canada - Monday, July 23, 2001 at 12:25:23 (PDT)
I have really enjoyed reading the site, which I stumbled upon while doing research for a "Teaching High School Science" course. I think much of my difficulties in teaching electricty units stems from the fact I have many conflicting conceptions of key concepts. Thanks also for your suggestions for vocabulary use to prevent vernacular misconceptions. Thanks!
Emily Gesner <ekgesnerathotmail dt com >
Toronto, ON Canada - Monday, July 23, 2001 at 12:24:52 (PDT)
great site!
ajith <heroajithatmultimania.com>
USA - Sunday, July 15, 2001 at 17:41:39 (PDT)
great site!
ajith <heroajithatmultimania.com>
USA - Sunday, July 15, 2001 at 17:40:32 (PDT)
Very interesting site. But I have to say my opinion differs as to how a lot of 'popular science' is wrong. Most of the things you find errors with are just simplified models. These models were created so that we can conceptualise the scientific principals. The creators of the models are not saying; "This is what's happening." They are saying "What is happening is _like_ this." I think that when it comes to scientific issues at an atomic and subatomic level (such as behaviour of light and electricity) we are looking into a world that is utterly foreign to us to a degree that we simply do not have anything to compare it too. It really is too strange in comparison to our everyday perceptions. In order for us to understand anything about it we have to create models that are 'similar to' what we believe is happening. These models are obviously simplified and may even be contradictory (e.g. light wave/particle duality), but they do the job. To pick them apart and point out where they are 'wrong' is missing the point of their existence. Can you really say this is what is _really_ happening, or are you just constructing another (perhaps more sophisticated) model that inevitably can be picked apart by another? Thanks for an excellent site that got me thinking.
UK - Sunday, July 15, 2001 at 05:43:40 (PDT)
> Most of the things you find errors with are just simplified models

Hi Gav! I think something isn't too clear about my list of textbook "errors." This list contains concepts which caused *ME* to have major misconceptions that seriously interfered with my own later learning. When I embarked on a mission to fix the errors in my understanding of simple physics, fixing these misconceptions led to "aha" experiences which allowed me to rapidly understand physics much more deeply, and let me see numerous enlightening interconnections which until that moment had been invisible. It would have been better if I had never encountered these misconceptions, because it's a major task to root them out of one's brain; to undergo "un-learning." This list of misconceptions is not just nitpicking. These are the things which gave me "cancer of the mind" as far as physics understanding is concerned.

As you say, in many cases it's not a question of right and wrong. But am I just complaining that simplified models must be simplified? Certainly not. I'm well aware that in science, ALL models are simplified, and ALL of them are "wrong" because they fail outside of certain limits, and they never contain everything that the real-world example contains. But this sort of "error" is not what I complain about. Instead it's a question of whether a particular explanation causes both students and educators to aquire serious misunderstandings which act as barriers to future learning.

For example, all chemistry textbooks start out with the Bohr model of the atom, where the atom is like a little solar system. This is completely "wrong" as far as chemistry and quantum mechanics is concerned, yet in my experience it has strong explanatory power and does not produce serious misconceptions. Therefore I don't mention it in my list. It's a simplified model, and it does its job without causing serious learning barriers. A similar situation occurs when we imagine that electric current is like a flow of liquid in a hose. This "wrong" idea has great explanatory power; it is not a "toxic misconception."

On the other hand, if you believe that electric charges flow through wires at nearly the speed of light, then your entire gut-level understanding of electric circuits will be profoundly distorted. For people who are certain that electric current is a fast flow, many other concepts which should fit together seemlessly, and produce important insights, will not fit together at all because the misconception blocks them. It's like trying to fit together a picture-puzzle when some of the pieces are from some other puzzle. It's like trying to get a machine to work, where some of the gears are bent or have extra teeth. It skews everything, and creates "conceptual tumors" in the midst of otherwise tightly-coupled conceptual networks. I know this is true because I once believed that electrons flow through wires at the speed of light. When I finally realized that this was a very serious error, my entire understanding of electric circuits shifted, and all kinds of other misunderstandings evaporated.

The "errors" in my list are not like the Bohr model of the atom, or the fluid analogy of electricity. Instead, it is a list of mind-viruses which do more harm than good (at least this was true for me personally.) In addition, it is a list of bad ideas which have "infected" the minds of educators, and which have spread widely throughout school textbooks.

The best way to find out if a simplified model is helpful or harmful is by exploring one's own conceptual networks for flaws, and by observing the consequences of removing those flaws. My list of misconceptions may read like a list of simplified models, but experience shows that it is something quite different.

Also check out Electricity Misconceptions
Bill Beaty <>
USA - Sunday, July 15, 2001 at 12:04:59 (PDT)

RE: The red/green gels in subparticle shapes to explain charge; And putting them in a cookie-sheet with round-beads-to-represent the 'aether' : indeed if the beads could be used to represent the surrounding either in which the 'A-field' is propagated, I think this works well as a 2-dimentional model. For Overhead-projector use, I envision a cookie-sheet with clear, flat bottom; or plexiglass with shallow rim. Anyways ,after some thought,it seems that the beads might not necessarily have to be round. I am talking about the actual properties of this either. Perhaps only EGG-SHAPED BEADS would allow A-field propagation(in our model) . It should be said,that in my 'musing' about this, Ther May Be No spaces allowed betwwen the beads, in that the real either eal-existances" might be truly continuious ,as in, geometric "clusters",completely filling space.(It's been shown by bucky fuller ,I think,that space can be filled completely with 2? regular geometric polygons. In this regard, I've seen a lot of theoretical work in sub-atomic physics ,,but you'll eventually run into works such as (Mr.)Cartan's theories. He seems to be trying to apply mathamatical properties to these eitherial propensities. But, it's like tryin g to sit down with eskimos,and enjoy their delicasie of smashed up duck-meat-and-maggot mix in a bag,,The 'understanding' just ain't there . Also,I believe Tesla lied about cutting the fish in half with the slinged rock,but there you go..good (best) site.CB
CRAIG BERTOK <cbertokathotmail dt com >
edmonton, canada - Saturday, July 07, 2001 at 10:50:48 (PDT)
I would like to see 'rectified' the reletionship betwwen your red/green gel sub-particle explanation with..the revelation using transformers, of what a 'magnetic circuit-A-fields' science RELLY IS! I am imagining a demonstration using thick gels on a cookie sheet,filled with small round white beads; where motions of the gels would interact with the spacing(waves?) of the white beads(WHICH ARE THE 'AETHER') Yes,I believe in the either and that it's understanding IS the new science. (In my anology, the areas of cookie sheet visable as the either moves would have to be the illusive "nothing".good stuff..) C.B.
craig bertok <cbertokathotmail dt com >
edmonton, canada - Saturday, July 07, 2001 at 10:23:22 (PDT)
Although I found your page on electricity to be interesting, it was a bit hard to follow. You jumped between the "right" way and the "wrong" way in the same paragraph and continually followed that pattern the whole way down, in each section. It wo uld be much easier to follow if you would explain what you believe is the correct way to state a concept (or define a term) and then used the same "correct" terms the whole way through the page. I have a view of electricity that I believed to be true and have been following for many years now. When you repeatedly bring up what you say is the "wrong" way, which is the way I was taught was the "right" way....oi! It makes it hard for me to diff erentiate. Maybe it's just me, but it seems that repeatedly bringing up the wrong ideas is only perpetuating what you seek to dispel. Give me a definition in the beginning...then I can adjust my meaning of the word. Then we can at least be using the same terms to explain the remaing sections.
Joe <xcam_1999atyahoo dt com >
PA USA - Wednesday, July 04, 2001 at 18:33:07 (PDT)
Thanks for the great Electricity FAQ. I think you should include the question, why does the US use 120V rather than 220V? Also, I wasn't able to easily find out what the relationship is between amperage and wattage, although you do mention that there is one, and any physics book would have it.
Robert R Schneck <schneckatmath.berkeley.edu>
Oakland, CA USA - Thursday, June 28, 2001 at 12:09:35 (PDT)
great site!
kamal <kamalattripod.cl>
USA - Tuesday, June 26, 2001 at 01:38:39 (PDT)
4 a whole bunch of crap about science, u made this site pretty interesting! good job i have just 1 question, whut xactly is THC? i know it is whut gets u high, but whut xactly is it, whut are all tha chemicals & such involved? well thanx anywho ~!peace!~
blac haze <blac_hazeathotmail dt com >
EDMONTON, CANADA - Sunday, June 24, 2001 at 20:56:49 (PDT)
4 a whole bunch of crap about science, u made this site pretty interesting! good job i have just 1 question, whut xactly is THC? i know it is whut gets u high, but whut xactly is it, whut are all tha chemicals & such involved? well thanx anywho ~!peace!~
blac haze <blac_hazeathotmail dt com >
EDMONTON, CANADA - Sunday, June 24, 2001 at 20:56:42 (PDT)
I've looked through your site before and, although I believe the Bernoulli explanation is more accurate, I think your theory is generally on firm ground. That is until I read some of your recent comments on the Kutta Condition and lift having somethin g to do with the angle of the trailing edge. If you are claiming, as I understand your comments, that the generation of lift somehow results from the aft portion of the airfoil being angled downward, then how do you explain the reflexed airfoil? On this shape, the aft portion of the airfoil is twisted upwards to reduce the moment generated by the airfoil and provide stability (see here http://www.apogeerockets dt com /education/images/Wing_Figure_03.gif for an example). By your logic, this airfoil should p roduce negative lift except at very high angles of attack (probably beyond the stall limit). In addition, the Kutta Condition has nothing to do with the angle of the aft section of an airfoil, but tells us that a stagnation point (i.e. a point where velo city is zero) must exist at the trailing edge for an airfoil to produce circulation and, by extension, lift. Thus, KC says that the trailing edge must be sharp, but has nothing to do with the overall shape or slope of the aft portion of the airfoil.< br> Jeff
USA - Thursday, June 21, 2001 at 17:37:27 (PDT)
cool site
hemanth <dthworldathotmail.com>
USA - Sunday, June 17, 2001 at 20:25:43 (PDT)
grea site!
rajini <rajiniattripod.de>
USA - Thursday, June 07, 2001 at 19:29:11 (PDT)
I am 28 years old and my son is 9. sense I was a child I was fascinated by electricity and other sorts of power.... my husband passed away 8 months ago so I am educating my son on what his father wanted him to no about plumbing and I am educating him on electricity... we did an experiment with the telephone line and batters .... and found that we could recharge batters from the low voltage. Have you ever heard of this being done before or are we the first . my son and I are buying a farm house out side of Redlands and I was wondering if you could tell me what would be the best way to go in creating are own electricity ( weather it be wind or solar panels or what have you) I would really appreciate any advice you could give. your web site is awesome keep it up thank you steve
steve benton <steveshutatyahoo dt com >
elsegundo, ca USA - Thursday, June 07, 2001 at 04:42:53 (PDT)
great site!
sathish <sathish_7atemail dt com >
USA - Friday, May 18, 2001 at 21:18:40 (PDT)
I'm interested in building a science fair website and I'm looking for good sources of ideas for science fair projects. If anyone could point me towards some I'd reall appreciate it. Thanks!
science fair projects <ihardriveathotmail.com>
San Francisco, CA USA - Tuesday, May 15, 2001 at 19:01:23 (PDT)
Good info! I LOVE the quotes. I'm sure my science-teacher friends are tired of me sending them the quotes. Too bad!
Robert <ka9vszatchorus dt net >
Madison, WI USA - Monday, May 14, 2001 at 12:40:59 (PDT)
> I have a couple questions left, though: (1) is there
> really a body of downwardly moving air behind an airfoil,
> or, as a comment a while ago said, is it not really moving
> down (relevent to the direction of motion?

It's really moving down. However, it "moves" in the same way that a smoke-ring moves. For every bit of fluid in a smoke ring that moves down, somewhere else there is another bit that's moving up, and the NET motion of fluid is zero, yet the smoke ring s till moves along. Or in other words: all the motions of fluid have closed-loop streamlines. Yet a smoke ring MOVES, and it transports smoke as it goes, and it can knock over objects when it strikes them. It behaves like a moving object, even though the overall transport of mass is zero. But the overall transport of MOMENTUM is not zero. As a smoke ring moves along, a region of nonzero momentum moves along, as if the smoke ring was a massive moving object.

With airplanes, the wings create downward-moving pairs of vortices, like two horizontal tornados side by side. The vortex pair moves downwards, and it transports momentum just like a moving hunk of matter. But people get confused when they find that the overall transport of mass is zero. But the motion of the mass is not important, it's the transport of MOMENTUM that's important. We can say that "wings throw air downwards." But then we must add something like this: "well, some air goes up at the same time that other air goes down, but the WHOLE PATTERN of swirling air moves downwards, and it carries momentum just like any massive object would."

People who have an emotional bias against the "Newtonian" description of flight will latch onto the fact that wings do not transport air downwards. They miss the fact that a moving smoke-ring is an example of a momentum-carrying object which transports n o air. And if I squirt you with a fire hose while you're underwater, the jet of water will knock you backwards, yet the net flow of water is still zero. Wings DO throw air downwards, but whenever you try to throw a hunk of fluid through a fluid-filled environment, the net transport of fluid goes to zero even though your "hunk" of fluid sails along like an independant object.

> (2) Does the increase in speed of air moving over the airfoil
>(even as shown in you pulsed-smoke windtunnel photograph)
>actually add to lift because of pressure differences?

Yep. Wings fly because the air goes faster over the top. But when we stop saying "air parcels must rejoin at the trailing edge," then our explanation is different for WHY the air moves faster over the top. The explanation is simple. It's because the trailing edge is tilted downwards. It's called the "Kutta condition" in textbooks.
bill beaty <>
Seattle , WA USA - Thursday, May 10, 2001 at 19:26:16 (PDT)

Hello, and excellent web site. I recently won Outstanding and Best in Category (astrophysics) awards at the state science fair, after receiving Outstanding in School and Regional levels. Much thanks goes to your help and mounds of logical information . I have a couple questions left, though: (1) is there really a body of downwardly moving air behind an airfoil, or, as a comment a while ago said, is it not really moving down (relevent to the direction of motion? (2) Does the increase in speed of air moving over the airfoil (even as shown in you pulsed-smoke windtunnel photograph) actually add to lift because of pressure differences? Just because the air never recombines to its original composition does not mean that it cannot accellerate, create a r elatively low pressure over the wing, and create lift. I am surprised that you did not include any geometrical info, such as the fact that higher center-lines in the airfoil created higher lift, though thicker chords create more lift as well as drag. Th is is understandable, as it is not very pertinent to the purpose of your webpage. Thanks again, please reply. 8^]
USA - Wednesday, May 09, 2001 at 18:28:19 (PDT)
Infrared as "heat radiation": By observing the wavelengths emitted by a non-luminescent object you can get an idea of its temperature - hence the term "thermal imaging" (I'm assuming it involves expanding the concepts of black body radiation to more co mplex structures - even if the math is complex, an imprecise mapping would be enough to make thermal imaging equipment). My understanding was that at a temperature of say, 37 degrees Celsius, those wavelengths were in the IR range. (In other words, yes, h eat radiation is just normal EMR, but thermal sensors do operate in the IR range).
Nick Coghlan <ncoghlanatemail dt com >
Australia - Sunday, May 06, 2001 at 07:32:02 (PDT)
why is there nothing on resistance
Shane Dale
USA - Thursday, April 26, 2001 at 06:19:03 (PDT)
Hey yall. Im doing a physics project for my highschool honors physics class. We had to make our own proposal for this project. I decided mine was going to be... The time it takes an icecube to melt with pressure being added on. Let me explain.. Im takeing 3 ice cubes... each consist of 2 table spoons. On the three different ice cubes Im adding weights to them and timing the melting time of each ice cube. MAKE SINCE?? I hope. Anyways.. I will be writing a lab report on this in the next week, I wa s wondering if anyone can help me with some equations to put on this lab report. I really have no idea which ones I would use for this expierment. Ill be looking forward to yalls help.. THANKYOU SO MUCH!!! Kacey
Kacey <Kacey338ataol dt com >
N/A, Tx USA - Monday, April 23, 2001 at 18:32:34 (PDT)
I've heard that it is a myth that the diresction that water goes down the drain is caused by the Coriolis effect. Is this right?
charlie s. <mathomhouseatskybest dt com >
USA - Friday, April 20, 2001 at 18:38:31 (PDT)
Im a first year teacher training student and I am doing an essay on childrens misconceptions associated with electricity, especially batteries and circuits.If anyone could give me some imput I would be very grateful.Thankyou!
Emma Foote <emmz60athotmail dt com >
England - Monday, April 16, 2001 at 15:13:24 (PDT)
Hello. Wonderful site. My son (11) has maintained since he was 7 that there must be a way to use magnetic force lift a rocket into space. Needless to say, he was excited when he learned about maglev trains and now wants to do his science fair proje ct on that subject. HELP!! He is only 11 but has grand ideas (he won best in show last year), but I need to get some down to earth info. on possible projects before he electrocutes us all. He insists on doing this himself, but won't be content with a st atic cardboard and magnet construction. Any advice would be greatly appreciated! Thank you, Chris
Chris <Chrispdrakeatyahoo dt com >
USA - Tuesday, April 10, 2001 at 07:07:24 (PDT)
I am currently doing a number of school assignments. One assignment is on electrostatics and the weather and another is on maximising the projection of the shot put. If anyone has any information which I could use in my assignments it would be greatly appreciated.
Carolyn Jacobs <cazzles84atexcite dt com >
- Saturday, April 07, 2001 at 22:11:27 (PDT)
I am doing a report in physical science and in searching for information i stumbled onto this site...I need some info on a couple questions and this place seems more than qualified, you will be credited in my report... What is a circuit? What are 3 basic components of a circuit How does circuit arrangement affect voltage and amperage? What is resistance ? What qualities of an item affects resistance? In the absence of resistance (in the transmissions wires), what should be the amperage around a series circuit? what should be the amperage around a parallel circuit? what should be the voltage around a series circuit? what should be the voltage around a parallel circuit? any information would be be great, just leave your name to be credited
ANDREW <crusade23athotmail dt com >
OR USA - Tuesday, April 03, 2001 at 18:55:56 (PDT)
Why Is electricity important? Why do we need electricity?
Aisha <girljustwants2havefunathotmail dt com >
tacoma, wa USA - Tuesday, April 03, 2001 at 16:32:21 (PDT)
great site
USA - Saturday, March 31, 2001 at 08:39:49 (PST)
Re: the lift problem. I've been a helicopter pilot for more than 30 years, and this is what I have to add to the mix. Both blade-tip and wing-tip vortices are caused by the difference in pressure above and below the blades/wings. There IS a relative induced low presssure abo ve and a corresponding relative induced high pressure below. This can be proven by watching the altimeter and/or the vertical speed indicators on the instrument panel. When a helicopter is picked up to a hover, way before sufficient lift is created for the act, both of these instruments show a definate decrease. Both of these instruments are barometric, and both react to changes in local pressure. The only way for them to read lower, is for a relative induced high-pressure system to be influencing the m. The rotor-wash under the blades is caused by the air circulating from the induced high to the induced low. Now, does this totally negate Newton? No, but it does lend credence to Bernoulli. Try this. Get a sheet of paper and hold by the sides with the thumb and fore finger of each hand at one end. Hold the paper just below your chin and blow fairly hard. The paper rises, doesn't it? There is no way for you to be blowing underneath the paper. Score one for Bernoulli. Helicopters are built with both symmetrical and asymmetrical blades, depending on what the aircraft's mission is. Both types work, but ALL blades have their curved surfaces on top. For anyone interested in rotary-wing aerodynamics, I highly recommend R.W. Prouty's books on helico pter aerodynamics. He is a former Chief-of-Design for both Hughes and Mcdonnel-Douglas, and he seriously knows of whence he speaks.
Mike <axolotl1951athotmail dt com >
Daleville, AL USA - Saturday, March 31, 2001 at 08:20:19 (PST)
Thanks for simplifying and correcting some misconceptions. I assumed Science(if I can safely call it that) was such a difficult Subject for me, because many of the explanations, theories, and facts stipulated in the past, simply didn't make sense, oft en leaving me confused. Reading your explanations give credence, and at least are more plausible, not confusing, or contradictory. I've not completed the entire list of topics, but be assured I will. You are absolutely correct; people have various definitions regarding the same words, subjects, etc., which are often diametrically opposed to the next person's, or what's written in te xtbooks.
Dorothy <Drthybrrn1505atcs dt com >
Paris, TN USA - Friday, March 30, 2001 at 19:23:15 (PST)
Love your site....Tom Bearden has advanced Tesla http://www.cheniere.org There is much to "see".....your time will not be wasted. All the Best........Les
Les Pastor <l.pastoratworldnet.att dt net >
Rocky Point, NY USA - Monday, March 26, 2001 at 15:16:31 (PST)
---1) We designate that volume of air in uniform, translatory flow with which a wing will interact per unit of time and specify its momentum as = 100.
---2) The velocity changes occasioned by the interaction effect a differentiation of the forces within the designate air mass.
---3) The residual velocity component of momentum, (arbitrarily) 80% we designate M/v; the differentiated pressure component - 20% - we designate M/p. M/v and M/p are equal to the constant of the energy inherent in the flow.
---4) The wing is sustained by a force acting at right angles to the direction of the flow and equal to that differentiated from it by the changes in velocity.
---5) In what must be one of the most fortuitous coincidences in all of physics, the pressure force that sustains the wing is of exactly the same magnitude as the pressure force - M/p - differentiated from the initial, designate (100%) velocity of the free stream by the interaction of the wing with that mass.---Conclusions and Commentaries on this to come. ---Richard Miller
< br> Richard Miller <richardmilleratrocketmail dt com >
Santa Cruz, Ca USA - Saturday, March 24, 2001 at 10:36:18 (PST)
Take a 36 inch evacuted tube and pour mercury into it and then place the opened end into a dish of mercury. The mercury will stabalize at a specific height. Is the mercury being sucked up by the vacuum above it? Or is atmospheric pressure pushing it up the tube? Suppose I could find a way to create a vacuum in free space. Further suppose I could place and maintain that vacuum over any object regardless of its shape or position. Suppose I place the vacuum over Santa and his Raindeer, and then I li ft and guide the vacuumm from chimney to chimney with Santa remaining stuck near the vacuum. At this point I really don't care if the forces involvled are caused by Newton or Bernoulli. I don't care if Santa is flying, swimming, or is experienceing bouy ancy. I don't care if the forces are static or dynamic. I DO care if one or several raindeer start flatulenting packets of hot gasses downwards, outwards, or upwards, that could shake my confidence. I am an inventor not a physicist, or an engineer. I am making human powered flying practical. Where can I get research money? Would anyone like to help out? Write me at Mike Genereaux at 236 S. Rainbow 497, Las Vegas, NV 89145 or call 702 862-8995
Mike <mdgenereaux asng ivillage.com>
Las Vegas, NV USA - Tuesday, March 20, 2001 at 09:12:57 (PST)
---Mrs NEWTON and BERNOULLI once again, chiefly, again, the topics of Books I and II of the Principia. These rest, ultimately, on the difference between solids and fluids. We all know that at a level so intutitive that's it's simple tautology to talk a bout it. Solid is solid; fluid is fluid. ---However, when one comes to consider the translation - uniform motion, as left to right - and transference of forces, which involve masses, momentum, and acceleration, it is quite a different matter. Here there is a very siignificant difference, and whe n one grasps it the matter of how lift is produced becomes quite clear. ---It begins with a very simple observation. The propagation of pressure up current from a source of resistance in a free stream, as a rock in rivulet. Newton knew of this as most of us do. All we have to do is think of flowing water, in a gutter, down th e drain, whatever, and we see that. From the source of resistance, at the speed of sound, pressure (a force) propagates upstream. ---This is perhaps the most important observation one can make as regards the nature of fluids and the difference between their inherent momentum and that of solids. You might think about it. -Richard Miller
Richard Miller <richardmilleratrocketmail dt com >
Santa Cruz, CA USA - Monday, March 19, 2001 at 10:53:33 (PST)
-----Mr. Connally: You write as if you understand the difference between velocity and acceleration, so perhaps you can help somebody who doesn't. I strap myself in my J-3, advance the throttle and ACCELERATE down the runway and into the air. When I ha ve sufficient altitude I throttle back and settle into the constant VELOCITY of equilibrium flight. The Cub never gives me any indication that it has passed from one regime to the other. It doesn't seem to know if the lift of its wing is from acceleration or velocity. Neither do I. Help. -Richard Miller
Richard Miller <richardmilleratrocketmail dt com >
Santa Cruz, Ca USA - Monday, March 19, 2001 at 10:25:20 (PST)
In a transformer, power is the same in both primary and secondary coils. If the second coil is connected to a load that requires more power that required, what would happen? For example, 10 Volts, 10 Watts (1 Amp because I=P/V) goes through the primary coil and jumps to 20 Volts in the scondary (P = 10 Watts because power is constant, I = 0.5 Amps because I=P/V). So does this mean that 0.5 Amps is going through the coil with 20 Volts pushing through it? What if the load connected to the secondary coil requires more current than possible (like 10 Ohm resistor connected to 20 Volts in the secondary requires 2 Amps and 40 Watts, exceding the 10 Watt limit)?
Leo <LeoXL258atyahoo dt com >
USA - Monday, March 19, 2001 at 09:20:10 (PST)
It's been a while since submitted to this page and cleared up all the misunderstandings about lift. I didn't imagine that anyone would pay attention, and no one did. Just part of my continuing education in epistemology. I'm idle for a few moments, however, so I'll dive in again. There were three books to the Principia: The first dealt with the physics of solid, palable, quantitifiable matter, and to it the three eponymous laws pertain, and hold up very well. The secon d book is entitle Fluid Mechanics and introduces an exponent, velocity squared, of which the reciprocal is the inverse-square law that featured so prominently in Book III. It's curious, but nobody ever pays any attention to thatr exponent, nor its inferences. It's used in the lift equation, as is necessary, but never in theorizing. You would think it was of no consequence. It is, however, very consequential. Maybe some day somebody will pay attention. -Richard Miller
RICHARD MILLER <richardmilleratrocketmail dt com >
Santa Cruz, CA USA - Sunday, March 18, 2001 at 13:55:03 (PST)
Now that I have read more of the volumes of debate over Bernoulli vs Newton, I must confess that others, including the author of this site have pointed out that both methods of analysis are correct. Before I go into my next point, I want to say that I really appreciate what Bill has done with this site. With some minor exceptions regarding his Bernoulli antipathy, of the issues I am familiar, I find his statements are correct; of the issues I am not familiar, I find his statements are fascinating and enlightening. One point I find disturbing is the author's repeated reference to the fact that airfoils causes a downward MOTION of air which via Newtons 3rd law explains the force of lift on an aircraft. In fact the airfoil causes a downward ACCELERATION of air. It i s the acceleration NOT motion of air that allows for a Newtonian explanation. After all, Force equal mass times acceleration (not velocity). This may seem like another picky detail since a downward acceleration must surely result in a downward motion. (Note: when I refer to 'down', I mean 'in a direction opposite to lift' - another fine point). But the distinction between acceleration and vel ocity is important because velocity can be misinterpreted to mean that air is being moved downward. In fact this is not true. AIR IS NOT BEING MOVED DOWNWARD. If with every passing plane, air were to move downward, we would be living in a much denser p ool of air. For the downward moving air must either move back up or collect near the surface of the earth. Likewise, if one assumes the downward motion of air creates lift, what happens when it goes back up? Is there an anti-lift effect created somewhere. The fact is Newton's Law does not apply to motion but "net" acceleration. What really happens is hard t o envision. For every molecule of air that moves down there is a molecule that moves up, but the downward moving molecules change speed more abruptly than the upward moving molecules. This allows a net downward acceleration to occur without a net downwa rd motion of air. Yes, it is true, right behind a wing the air will be moving downward, but an equal number of air molecules must go up to offset. And the fact is, the upward moving air is ocurring at the same time as the downward moving air, so overall direction of motion is zero; and therefore, downward motion is not a proper explaination. One way to imagine the downward acceleration without downward motion phenomenon is to think of a wave in the ocean. If the wave truly represents moving water then every wave would have to climb up on to the beach and hike inland to make way for the waves behind them (and additional mass of water). But water does not collect in great masses on the beach. If you were to put a cork in the water you would find that cork remains relatively motionless when compared to the wave passing underneath. So, the wa ter molecules are not moving with the wave, but the change in acceleration of those molecules causes the wave to move in a net direction. Its also that net acceleration in a particular direction that helps to explain beach erosion (but that is another su bject). Therefore it is the transfer of acceleration of molecules of air in a downward direction that provides a Newtonian explanation for lift, not the downward motion itself. Another term for this transfer of acceleration is 'a pressure wave'. Some of the e-mail responses have pondered: "what makes the molecules of air travel faster over the top of the wing?". This is another question that can make sane minds go mad. The fact is from the molecules perspective, it is merely being pushed out of the way by the wing, which does nothing to explain why pressure drops when this happens. The wing cannot transfer energy to the molecules of air because the wing would then have to constantly lose energy. But that energy to dodge the wing must come fro m somewhere and in-fact it does. The energy comes from the molecule itself (and its neighbor molecules) in the form of lost pressure. Because the molecule eventually comes to rest again, it regains its lost pressure. When all of this is viewed from the stationary wing - moving air perspective, it looks like the molecules are suddenly accelerating to get over the wing. Another way to look at this is to think of a long and tall stack of layered fabric. A wing passing through this fabric would cause the layers passing over the top of the wing to stretch in order to get over the top of the wing. This stretching of fabric is analogous to the streching of air molecules that creates a loss of pressure over the top of the wing. Now as for the author's assertion that Newton should at least be used in conjunction with Bernoulli to explain lift, I agree -- with the caveat that students must NOT be taught that two different effects are being combined. These are two different ways o f looking at the same phenomenon (I believe the author has agreed with this point).
Tim Connally, PE <flyintlcatneteze dt com >
Concord, CA USA - Wednesday, March 14, 2001 at 16:40:53 (PST)
So how DOES electricity work? I passed my (civil)engineering license exams by chanting "twinkle twinkle little star, V is equal to IR". After reading all the stuff that ISN'T true, please fill the void!
AMC <crickmaataol dt com >
USA - Tuesday, March 13, 2001 at 19:07:23 (PST)
I get very tired of reading about pedogists who insist on debating who, between Newton or Bernoulli, should be given credit for 'inventing lift'. I've heard some educators make the statement that aircraft lift can be attributed approximately X% to Newtonian forces and Y% to Bernoulli. A totally absurd notion.

Fortunantly, I have read the correct answer a time or two. Unfortunanly, I do not see it here. The only answer to this debate is: lift can be explained 100% by Newton's law of forces and lift can be explained 100% by Bernoulli's law of fluid motion. These are two different laws.

Newton requires the understanding of his third law of 'motion' (a misnomer - should be third law of 'force') that states for every action (force) there is an equal and opposite reaction (force). Also one must understand Newtons equation of Force F=ma where F is force and m is mass and a is accelleration. The downward accelleration (not motion) of air (with a mass density) causes and equall upward lift force on the aircraft which counters the downward force of gravity. This downward force of gravity is really a relatively constant downward accelaration applied to the aircraft's mass (F=ma). 100 % explaination.

Bernoulli's law of fliud motion does not deal directly with forces. Instead it balances energy. It simply means that the additional energy require to move air a longer distance over the top of a curved airfoil is balanced by a cooresponding loss in potential energy from pressure. The is a greater loss of pressure on the top surface of the wing than on the bottom surface. Yes, this is a 100% explaination for lift.

Why do symetric wings work - or how does a plane fly upside down? Because the angle of attack is a vital component assessing fluid motion. A higher angle of attack causes the airflow to split lower on the forward edge, this causes a greater distance for air to flow over the top of the surface than the bottom. Also, the downward acceleration of air along the back edge of an airfoil can cause the air to meet at a lower point along the back edge as well. Thin foil wings like the Wright brother's Wright Flyer actually have a complicated flow pattern. In a simplified view, the underside of the wing fills with a rotating 'pillow' of air that makes the wing act like it has a flat solid bottom.

Although both laws provide satisfactory explanations for lift. Only one law proves useful in quantitizing lift. This is Bernoulli's equation. Aircraft designers cannot use Newtons equation of force to predict how well a given airfoil (shape) will perform. Newtons laws simply do not provide any means of predicting how much downward accelleration of air will result from a given wing design. Bernoulli's laws, however can be used to predict how much change in pressure will occur for a wing design at a given angle of attack, ambient air pressure and airspeed. Although, even Bernoulli fall short because of the complexity of airflow. Aircraft designers inevitably end-up using a certain amount of wind-tunnel testing in a trail-and-error approach to design. One interesting note. Actual analysis of wind tunnel data show that there is a loss of pressure on most of the bottom surface of a typical airfoil, as well as the top surface. Students are often taught that there is a pressure increases on the bottom surface, when in-fact only very small areas show a higher than atmospheric pressure. Is is the overall pressure difference between top and bottom surfaces that causes lift, not 'suction' from the top surface or 'pushing up' from bottom.
Tim Connally, PE <flyintlcatneteze dt com >
Concord, CA USA - Tuesday, March 13, 2001 at 17:04:32 (PST)

I just read in the April 2001 issue of Discover Magazine, Why We Go Up, that Anderson calculates a 250 ton airliner pumps down 250 tons of air every second. I think he is pissin on my boot and calling it water. I calculate that 250 tons of air takes up 6,640,106 cubic feet of space. That is almost the same volume as the Hindenburg. Does a 250 ton airliner realy make contact with 6.6 million cubic feet of air and also pump it down?
Mike <mdgenereauxativillage dt com >
Las Vegas, NV USA - Monday, March 12, 2001 at 09:28:32 (PST)
What's on the other side of a Blacl Hole? Could it be the aftermath of a Big Bang and a bunch of other people rather like us ponderring Black Holes in their back yard? Hay, it's got to go somewhere, bubble, bubble, toil and trouble around and around it goes.:)
BobRiceman <rricemanatcitlink dt net >
Laurens, NY USA - Saturday, March 10, 2001 at 18:22:06 (PST)
i need to know the difference between 115V/single phase, 220V/single phase, and 220V/3 phase. i need a diagram showing the different circuts. could you please help me?
jerry mcgeachy <mcgeachyjrathotmail dt com >
san diego, ca USA - Thursday, March 08, 2001 at 18:54:50 (PST)
Im a doctor(M.D),Internist. Besides the human body and pathology,I have a very curious part to myself ie I have many interests.Tonight I started thinking about electricy,found your web page and read almost every part. Thanks Al
AL lebarge <cardiodoxathotmail dt com >
Virginia, MN USA - Tuesday, March 06, 2001 at 20:51:01 (PST)
I am starting phase 2 of the coanda effect, I personally think that the bournalli effect may help explain why bees and other insects can fly, i am open to any suggestions about the coanda or the bournalli effect
Kyle Gross <Krys322atmsn dt com >
paris, tx USA - Saturday, March 03, 2001 at 14:51:17 (PST)
I came here via a link on badastronomy dt com . Imagine my surprise when Norton Internet Security's parental control software reported that this site is blocked due to cult/new age content. After turning off parental controls--I'm the parent with the password--I found a site that does not seem to have any such content. Of course, I have not examined every page of the site, but the general theme of the site isn't cult/new age stuff. I guess it just goes to exemplify the fallability of parental control s oftware which I consider a necessary evil.
Russ <russatrussellcannon dt com >
USA - Friday, March 02, 2001 at 01:12:16 (PST)
Bill-Great site! I've linked to you on my own site. My son (grade 4) and I are now building a VDG on our own. It started as a science project for school, but has instilled as sense of interest of electricity for my son. In all our searching, your site has given us the most information on this subject--thanx!!
Noni <noni120ativillage dt com >
Canada - Thursday, March 01, 2001 at 12:53:20 (PST)
Believe it or not, in my AP Physics class in high school, we used a really crappy textbook that listed "frictions" between common materials, like between two pieces of copper. Of course this is ridiculous, because if they really we able to somehow get all the oxides, and air and other stuff away from the mating surfaces of the copper, it would be one piece of copper. So their measurements are bogus.
John Luebs <jkluebsatluebsphoto dt com >
Camillus, NY USA - Monday, February 26, 2001 at 17:16:29 (PST)
Your site was really helpful to me. I was wondering if this electrostatic motor would be safe to use in a gr. 8 science fair. Please awnser my question ASAP! Thank you, Matt
Matt <bigguy10_5athotmail dt com >
Canada - Friday, February 23, 2001 at 11:04:54 (PST)
Regarding: ...no use of the convenient fact that rate of charge flow is proportional to charge speed. This greatly clarifies electric circuit concepts. High current is FAST charges. Zero current is STOPPED charges. Not quite right, HIGH current can be fast charges, but it can also be lots and lots of slow charges. The water flow in the Mississippi is slower than that out of a fire hose, but there is much greater flow in the great muddy than from the fire hose. This is the only thing I have found wrong on your pages to date -- the material is EXCELLENT -- I highly recommend to anyone interested in science, not just from K-6 but from K to PhD -- Keep up the good work, Kevin
Kevin G. Rhoads <kgrhoadsatalum.mit dt edu >
USA - Friday, February 23, 2001 at 09:24:24 (PST)
How Do You Genorate Your own electricity for like a school project?
John Smith <jsmithataol dt com >
USA - Friday, February 23, 2001 at 08:07:26 (PST)
Hi, I have several questions that I can't find clearly explained. What is the voltage after the "light bulb?" Say we have a 120 W bulb, I think it should draw 1 amp on a 120 volt circuit. The amps must still be going back, so to speak, but what about the voltage? Resistance, they say, drops the voltage. Something is " used up" somewhere. Can there be zero volts to ground with amps "moving?" I understand it as "zero with respect to ground," but what is the voltage of ground? Is it wrong to think of the resistance as the work done? It is what will bog-down the generator, isn't it? How do the 3 three wires in a 3 phase 120 volt circuit share the wires? It is easy to see in a six wire circuit, but I don't get the three wire set up. On a related subject, what is the phase relationship between the two wires comming off of each end of a generator? How does this work to get 240 volts to a stove? They say that directly opposing phases cancel out, so what happens in the stove elements? (I understand the third ground wire to supply 120 to the stove clock etc.) I suspect the phases are opposing because in a 3 wire 120 volt circuit, the third wire is neutral ONLY because of opposing flow; 5A going one way and 5A going the opposite way at the moment equals NO current. But is there voltage? If the loads are equal i s there no shock hazard? (I always pretend that there IS!) How do phases add up when used on a single phase load? The book I have shows a Delta connected transformer giving 240 from two of the legs, and 120 from one leg to ground. On the wye connected system they say it is 208 volts. "But wait," they say, "it is not 104 volts to ground but 120." The 208 is from phase difference: The momentary voltage of one wire is at 120 volts and the other is at 88 volt adds up to 208. Why does this not happen on a delta? I do see there is 208 volts from the "high leg" to ground though. Thats all for now, Thanks, Jay Z. Freed
jay freed <freedatgbis dt com >
carson city, nv USA - Wednesday, February 21, 2001 at 19:02:27 (PST)
This site is wonderful and I appreciate you displaying this information on the Internet. Some things I didn't even know are here.
TT Chen <none>
Berkeley Heights, NJ USA - Tuesday, February 20, 2001 at 19:00:53 (PST)
THANK YOU for offering some insight to common misconceptions about science! Well done. I appreciate the links to further reading.
Aimee <akbatunr.nevada dt edu >
NV USA - Saturday, February 10, 2001 at 01:48:49 (PST)
When air pressure drops (ie. when a storm is approaching) does it affect the flight of birds? Do they keep to their nests because they have trouble flying in the lower pressure? If so, at what pressure will they do this?
sally <stromblyatalbion dt edu >
albion, mi USA - Tuesday, February 06, 2001 at 14:06:07 (PST)
Why is the symbol I used for electrical current V=IR
regina poulton <rpoultonatrhnetorg>
henrietta, NY USA - Friday, February 02, 2001 at 07:06:54 (PST)
Let me put this out there for discussion. It drives me crazy when people say "It's not voltage that kills, it is the current that kills". It is the same as saying, "The guy didn't die from the 500 ft fall, it was that 'hitting the ground' part that k illed him". Just as the fall caused the guy to impact the ground, the voltage (potential) caused the current to flow. Voltage and current are directly related. I think I know what is going-on though. It just so happens that the units that we chose for current and voltage are such that we "see" a relatively large number for a voltage that causes a relatively small number for a lethal current. People see this and conclude that the tiny current is very devastating for its magnitude. It would be like so meone concluding that 100 pennies are worth more than 1 dollar. We could turn the situation around and measure current as electrons/second (instead of coulombs/second) and we would get the reverse for the magnitudes of the voltage and current. If I told you that it took 10 billion billion billion electrons per second to kill, but it only took 100 volts, you would probably conclude that "hey it's not the current that kills, it is that tiny voltage". If I'm wrong, please post a comment.
USA - Tuesday, January 30, 2001 at 18:45:11 (PST)
I am a first year science teacher and have found many mistakes in the pre-existing science text. I have been researching some Introductory Physical Science Texts and happened upon this site. I teach middle school age and wondered if anyone has a reco mmendation for a good intro tho physical science text.
O'Connell <pictsidheatyahoo dt com >
Cranford, NJ USA - Tuesday, January 30, 2001 at 09:54:19 (PST)
I am a first year science teacher and have found many mistakes in the pre-existing science text. I have been researching some Introductory Physical Science Texts and happened upon this site. I teach middle school age and wondered if anyone has a reco mmendation for a good intro tho physical science text.
O'Connell <pictsidheatyahoo dt com >
Cranford, NJ USA - Tuesday, January 30, 2001 at 09:53:16 (PST)
Do ancient unexplained artifacts and high technology potentially provide evidence of pre-flood civilizations? Do 800 Billion fossils of all types in the Karoo Bone yards provide additional evidence of a worldwide flood? Does the Bible mention dinosaurs ? Is there an easy explanation for fitting dinosaurs on the ark? Is there a reason that scientists cannot do on purpose in the lab what they claim happened by accident? Is evolution the worst theory ever to fit known facts?-- Man! Mutating Moth Myth Manufactured; Mutating Moths A Mirage. Maintaining Materialist Membership Mandates Mouthing Mad-Cap Moth Mutating Mythology. Moreover, Moths Maintained Multi-colored Manifestation for Millennia. Mysteriously, Midnight Moths Monitor ed on Maples Mid-day? Most Moths Manipulated Manually; Mounted on Maples;Made Motionless, "Mechanically";. Is there evidence that dinosaurs did co-exist with men in agreement with the Bible and in opposition to the theory of evolution? Do Giant versions of some of today's plant, insects, animals and "Mega" Men prove a stumbling block for evolutionary theories? Hello! Is there an unmistakable Message (from God) in the cells of every living thing? YES! http://msnhomepages.talkcity dt com /spiritst/s8int/phile12.html Ooparts & Ancient Technology-Evidence of Noah's Flood? http://msnhomepages.talkcity dt com /spiritst/s8int/phile16.html Twentieth Century Dinosaurs? http://msnhomepages.talkcity dt com /spiritst/s8int/phile16A.html History, Archeology & Art Crawling with Dinosaurs With Some Size Estimates At 8 to 10 Feet Tall, Meganthropus Would Have Gone in The First Round http://msnhomepages.talkcity dt com /spiritst/s8int/phile21.html There Were Giants In the Earth in Those Days-And Afterward Put your hand on the radio? Say this prayer I wrote myself? Become a "Prayer Partner"i.e.; Send money? Though they have hair like Charleston Heston (in his role as Moses after receiving the 10 commandments) What really matters is: http://msnhomepages.talk city dt com /spiritst/s8int/phile7.html What the Bible Says Concerning Salvation-Not Slick-haired Preachers No backwards collars, no funny hats, no special vestments, no accoutrements -no titles such as Father, Rabbi or Teacher as Jesus Commanded; and they called themselves: Christians? http://www.insidetheweb dt com /messageboard?mbs.cgi?accnt=mb796603&TL= Neit her Catholic Nor Protestant; A Christian Only! Take care, No HTML here? Paste: http://msnhomepages.talkcity dt com /spiritst/s8int/phile12.html into your address bar.
s8int <s8intatemail.msn.com>
sac, ca USA - Tuesday, January 23, 2001 at 00:03:35 (PST)
Does soda speed up the process for food to rot?What is in soda that melts foods such as salt and sugar?
Catherine <cadifponceatyahoo dt com >
Pasadena, CA USA - Friday, January 19, 2001 at 02:13:07 (PST)
I flew a few prop planes during my USAF career and thank God I didn't have to worry which side was lifting and which was pushing. Yes, I dutifully tried to absorb all the intricate bits of 'wisdom' that were forced upon me, but it all boiled down to t he fact that there was not a damned thing I could do about it. Either the bitch flew or it didn't. Some thing that has always piqued my curiosity is: A propeller blade is designed much like an airfoil in cross section. Does the prop pull the plane alo ng or does it bite into the air?
Jack Terpening <ibjackataol dt com >
Casselberry, FL USA - Wednesday, January 17, 2001 at 16:44:18 (PST)
Why doesn't my electric stove electrocute me? Thousands of watts of power, metal pans, how is it safe?
Paul <paulintahoeataol dt com >
NV USA - Wednesday, January 17, 2001 at 11:08:47 (PST)
SUGAR LAND, TX USA - Friday, January 12, 2001 at 12:11:39 (PST)
Lets assume it is true that a wing can produce its own support by throwing packets of air downwards. What is being said is that tools can produce forces. Now based on this logic lets ask, "Does a hammer produce a force called smash by driving a nail? Does a knife produce a force called slice by cutting a finger? Do people kill people, or do guns kill people? If there were to be a ban on hammers can houses still be built? Is a hammer the only tool that can control dynamic momemtum transfer? If we banned wings would flight be possible? Is overcoming parsitic drag a prerequisite for the development of flight? Does a balloon fly or does it not? Does a wing experience bouyancy? Do all objects immersed in a fluid experience bouyancy? Do we need a vi scous fluid with stagnation points for flight? What happen in a spuerfluid? Would we get flight or bouyancy? Does a wing gain a mass and lose a mass, like a jet engine? The air that is going downwards from a wing, is it collinear and coplaner with the wing as is required for equal and opposite reactions? Is it equal and opposite to the force of gravity? Can I make you fly by stretching a streamsheet on the top of you? Can I control your flight by manipulating the sheet? Do I need a definition of fli ght? Can I make anything fly including non-airfoils at any position (any angle of attack)? A duck has flown for millions of years, by copying a duck will I fly like one, or quake like one? Do I quake? Or can I fly?
Las Vegas, NV USA - Friday, January 12, 2001 at 10:29:33 (PST)
What is an electrical arc and why does it generate such heat?
Josephine Spalding <Spaldingatusitc.gov>
Washington, DC USA - Wednesday, January 10, 2001 at 13:17:08 (PST)
I greatly enjoy your quest for clarity and the great hunger for useful statements about phenomena, even though the "explanations" take effect only mentally, and require constant improvement.(example: why wings lift) Fortunately, we come prewired with a difference detection program - which, although not to be blindly trusted, can nevertheless bail us out of abstract blind alleys - let me give an example from a conversation with a six year-old: Dad (pointing to ship model on wall): What's that? Sixer (emphatically): A boat! Dad: What is a boat? Sixer (slowly): It's a thing you go in and you can go on the water. (thinking lake, thinking bathtub) Dad: Can you do that with that? Sixer (laughing): "No, 'course not..." Dad: Why not? Sixer: It's not a "real" boat... Dad (feigning perplexity): But you said... One point for all of this (and there is a point, somewhere) is that the ability to discriminate between objects and their representations - phenomena and models of phenomena - is somehow basic, and to lose or forget this is to court stupidity, insanity, w hatever. From an engineering standpoint one might say that the bright child is on the point of the graph where fun crosses truth... may we all continue to talk to each other from that state space... gardner/salford
C Gardner <crgardneraturban-hq dt com >
Salford, Pa USA - Friday, January 05, 2001 at 06:31:05 (PST)
What exactly is this??
USA - Wednesday, January 03, 2001 at 10:35:08 (PST)

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