Down wind faster than the wind

[humber]

Seeing how relative and absolute are sort of completely opposite, I can see how that would make them equivalent.

Quit now. My model is just like the FI case, you aver is valid, H'ethetheth.

They are indeed right; a treadmill is an object, not a frame of reference, nor as some people seem to think some people think, a fan.

That is right. The model is real. It is an object. No part of it may escape Newton's laws.

Also correct. Objects are indeed not frames.

That, or they are objects moving in different frames.

There is no the Newtonian frame.

Newton thought so. Good enough for me.

What your statements above illustrate, humber, is that you should familiarize yourself with reference frames and co-ordinate transformations. A frame of reference is just what it's called; it is a vantage point from which one describes the physics of some phenomenon. You can describe the cart in a frame of reference fixed to the cart, or one fixed to the earth, or one that is fixed to Uranus. The point is, if the cart works in one reference frame, it will work in all others. The treadmill illustrates in a convenient way that it works in a reference frame fixed to the cart.

Most of the things you say above are impossible to say if you understand this. I don't think it is shameful in any way that you don't, but your reluctance to learn is. You insist that you are put through paces that if followed, will lead you (with arithmetic) to the conclusion that the cart works. There is a reason for this.

Sorry, H'ethetheth, you cannot say I did not try. That is all from a sales brochure you may have read.

 

[sol invictus]

Newton thought so. Good enough for me.

Look - a concrete statement emerged from your fountain of meaningless gibberish. And guess what... it's completely wrong!

Newton, along with Galileo and every other physicist since, knew full well that there was no such thing as a unique frame. All inertial frames are equivalent - that follows immediately from Newton's laws, see e.g. http://farside.ph.utexas.edu/teaching/336k/lectures/node25.html . Newton thought quite a lot about this, as demolishing humberian and pre-Enlightenment ideas about absolute frames of reference was one of his greatest contributions to science. About 350 years ago.

 

[spork]

...demolishing humberian and pre-Enlightenment ideas about absolute frames of reference was one of his greatest contributions to science. About 350 years ago.

Where is Newton when you really need him!?

As a complete tangent it's interesting to note that, like humber, Newton remained a virgin until his death (and was apparently proud of that fact).

 

[humber]

Look - a concrete statement emerged from your fountain of meaningless gibberish. And guess what... it's completely wrong!

Newton, along with Galileo and every other physicist since, knew full well that there was no such thing as a unique frame. All inertial frames are equivalent - that follows immediately from Newton's laws, see e.g. http://farside.ph.utexas.edu/teaching/336k/lectures/node25.html . Newton thought quite a lot about this, as demolishing humberian and pre-Enlightenment ideas about absolute frames of reference was one of his greatest contributions to science. About 350 years ago.

His word over yours. Guess who wins?
ETA:
You are Wikkiable, oh so Wikkiable. What you don't understand, is that the very ideas you use, mean that there is nothing to gained over simply taking Newton's view. It's too blue collar for you, that's all.

 

[humber]

Where is Newton when you really need him!?

As a complete tangent it's interesting to note that, like humber, Newton remained a virgin until his death (and was apparently proud of that fact).

My bitches don't agree.

 

[John Freestone]

Simple mental test. Replace the belt with a toothed version, and the drive wheel with a mating gear. Backwards, for sure. A weight on the cart drive wheel may do. Perhaps even blocking the laminar flow from lifting the wheel may also indicate the same?

I have simply run out of ways of expressing it. If objects can travel without kinetic energy, doesn't that actually contradict the idea of relative frames and or "equivalence"?

No, it doesn't. As I tried to point out earlier, if you are standing still on a still day, you (I believe) will say that you are motionless, and that you have zero kinetic energy, but you are moving extremely fast. You fail to acknowledge that kinetic energy is expressed relative to some object or frame or origin that is considered, arbitrarily, as motionless; that is all. It has been explained to you over and over and over, and you have given no refutation of it whatsoever, only a refusal to accept it and a pre-Enlightenment view that there is just real ground of the earth to measure everything by and real wind that moves relative to that. Seriously, your arguments belong to some peasant living hundreds of years ago. The Renaissance might as well not have happened.

ETA
Jonn Freestone:
Please stop bothering me. I read and understood that cart description. I made only one of many criticisms.
Physician, heal thy self.

Perhaps you can't count beyond 1. You made at least half a dozen ridiculous criticisms. If I am "bothering" you, it is an unfortunate side-effect of your posting endless unsupported claims, and my wish to engage you in considering their logical consequences - all this, in fact, in the interests of the general reader: I have absolutely no illusion that you will ever change your opinions, if you actually have any.

But again, rather than deal with those logical consequences, expressed as questions, in my post and at least 3 others since I last posted, and tell us the answers, you say things like "Stop bothering me" or "I'll post that later", or you ignore it entirely and move on to a new 'criticism' or return to restate an old one.

Do us a favor, please.

Get some of those guys in here (preferably people with credentials that can be verified). Ask them to explain it to us. Because, no offense, you haven't been very convincing.

That's right. Humber's so-called "criticisms" are expressed in language that hovers delicately between some personal and (I gather, often incorrect) interpretation of technical terms and utter nonsense prose, and it veers one way or another depending on how much his back is up against a wall. Sometimes it sounds like he is really struggling with English, maybe it's his second language, which gives the impression that maybe we just don't understand him and that's not his fault. Then, suddenly it is perfect in its grammar and makes some kind of sense linguistically, but unfortunately doesn't relate to the subject in any way. The next minute, if he's really pushed, he'll just do something later, or he's already done it, or he's not going to respond to someone bothering him.

I wouldn't bother him if he was just ignorant.

Hi Humber. Perhaps you can respond to my hypothetical set-up in #2240, with particular focus on whether any wind (or lack of it) is real or not as perceived by a person standing (still) on the ground in the northern hemisphere or another person standing in the southern hemisphere? It seems you may have missed it in amongst all the other messages...

Hmmm, that's a good idea. Or perhaps he could give an answer to my question - just define 'real wind' - or to describe exactly what test could be done to tell if the porch was or was not on a giant conveyor belt - or maybe a few others people are waiting for answers to. They won't come, not in any kind of English we can make heads or tails of.

By the way, if anyone has the faintest clue what humber thinks this model will do on an incline and/or on a level belt - please tell me. I'd love to go prove him wrong so he can come up with another brilliant theory. Although I admit it'll be tough to improve upon the "hopping" theory.

Well, he seems to have restated that (kind of) since you posted this. He seems to suggest that it "won't do as well" on the level. It could be good to press him on exact effects: will the cart be seen to progress faster on an upwardly inclined treadmill or a level one? He seems to suggest indirectly that it will [ETA: ...go faster on an upward incline]. Again, somehow in Humberland, a component of the cart's weight pushing it backwards is causing the 'artefact' of it moving forwards uphill and uptread until it falls of the top. Maybe if you put it at about 89 degrees you'll have an escape-velocity cart-launcher and NASA can save a bundle.

I imagine that video evidence is already there to demonstrate the opposite for those with zero imagination, but it doesn't matter, whatever you present will be "wrong". Even if you run it at the balance point where it's on an incline just right to keep it roughly still, and then lower the incline, and we all watch the cart move forward until it falls off the front of the treadmill, he'll invent some new ridiculous interpretation to do with coriolis forces or ley lines, or just restate one of his earlier bits of garbage to "explain" it.

I keep wondering, have you replaced the prop with a flywheel yet and videoed the result? That would be fun to see how he squirms out of it skittering off the down-tread end (just as you have demonstrated it does without the prop). As others have already said, with increased friction or a mass like a flywheel to accelerate, it will perform "worse" - falling off the back end faster. As I pointed out, with no response, Humber suggests that a cart will go better with its brakes on. He probably doesn't realise that's what he said, but he did say that tying a piece of rag round the drive-shaft, or another method of increasing the friction, would improve performance, or replace the performance of the prop.

There probably isn't anything you can do, spork, except enjoy the ride. What can you do with someone who suggests that if Terry (say) fell out of your cart travelling at windspeed on the treadmill he'd get sucked into the prop, and "your model doesn't predict that stupid event"?

No, Humber, it doesn't predict it. Know why? Because it's just your stupid prediction. If you fall out of a car, even a very tall car, travelling at windspeed, you hit the ground exactly below the door you fell out of. If you fall out of the big cart going along the ground at windspeed - the same result. If Terry took a ride on the treadmill version - same result.

You might bounce off the ground into the prop as the ground accelerates you, but if you shout quickly to the observers before your demise you would be able to verify that you're not sucked into it, and don't fall backwards.

Your stupid prediction was supposed to indicate one difference between those frames of reference, I think (though no doubt you'd deny it now). You made that mistake weeks ago and have failed to mention it since, like all your other mistakes. You're pretending to know better than everyone else to cover up all those stupid mistakes. Now, having stated again that you could ascertain the difference between frames, I asked you to elaborate, elucidate a single way that does not depend on outside observations. Sorry to "bother you" with that detail. What, are we supposed to just take your word for it? Like someone in court saying they have definitely got an alibi, next question please?

 

[Michael C]

Newton, along with Galileo and every other physicist since, knew full well that there was no such thing as a unique frame. All inertial frames are equivalent - that follows immediately from Newton's laws, see e.g. http://farside.ph.utexas.edu/teaching/336k/lectures/node25.html . Newton thought quite a lot about this, as demolishing humberian and pre-Enlightenment ideas about absolute frames of reference was one of his greatest contributions to science. About 350 years ago.

His word over yours. Guess who wins?

Newton's word? Where? Please quote the passage from Newton's writings that refutes the above statement.

 

[H'ethetheth]

Quit now. My model is just like the FI case, you aver is valid, H'ethetheth.

Models have nothing to do with my remark. If you can state, without blushing, that the very relativity of inertial frames makes them absolute, you do not understand what you are talking about.

That is right. The model is real. It is an object. No part of it may escape Newton's laws.

Yes. However, the realisation that objects are not reference frames is not interesting or in any way pertinent to the discussion. I think we can all agree on that. What is relevant to the discussion, is that you seem to think that reference frames are instruments of deception that lead to the false conclusion that this cart works.

Newton thought so. Good enough for me.

From what I've read, Newton thought that if such a frame should be defined, this "mother of all reference frames" would be at rest relative to the fixed(!) stars. For some time now, physicists realize that the stars are in fact not fixed, and therefore such a frame cannot be defined, nor was it ever necessary. All inertial reference frames are equivalent. They are decidedly not equal though.

Sorry, H'ethetheth, you cannot say I did not try.

Indeed, and I'm not about to. It's just that the things you say about reference frames can really only be said in earnest by someone who isn't quite familiar with them. Your use of the term is muddled; sometimes imprecise, sometimes incorrect.

Now, I'm honestly trying to understand your position, so could you help me out here?
Is it your understanding that the wind we say is generated by the treadmill is just the air dragged along by the surface of the belt by viscous friction?

 

[Modified]

No, Modified. You are right, it has been explained, but it is wrong. I know what you are saying, but the results produce a cart that travels without kinetic energy w.r.t the ground.

The ground is irrelevant in the treadmill case, since the cart on the treadmill does not interact with the ground.

The ground reference is special because it IS common.

It exists in both scenarios, but it has a different relation to the ground and air, which are the things that have an effect on the cart.

Please do this experiment. Take the treadmill and bury it in the ground.
Disassemble the model. The belt becomes a road moving backwards. That is correct, moving backwards relative to the ground, relative to you. I think that you all perhaps making the road the 'earth'? For that you need a disembodied observer.
If I power that road, it is correct. Now I am both the real world and the new treadmill side observer. That tells me that if the cart is coupled by friction to the road, it goes backwards, w.r.t the ground. If it happens to stay in my view, because it is not coupled by sufficient friction to the road,then it will hover motionless w.r.t the ground, and to me.

The same thing will happen on the road. Any vehicle with no friction will be blown at the speed of the wind. Whether on the treadmill or on the ground, such a vehicle will have zero speed with respect to the wind and wind speed with respect to the surface. The situations are identical.

That is consistent with every thing. No velocity (or just a little) no KE.

The KE with respect to the air or surface will be the same in both cases.

This model is entirely in keeping with the way you construct your view, but contradicts yours, because your inferred velocity is not correct, so the KE is not correct. The cart is artificially placed where it is, that overcomes the missing physical translation, from - beltspeed, through zero w.r.t ground, then on to windspeed w.r.t, and the models claimed emulation.

We are only interested in what happens at and near wind speed. Placing the cart on the treadmill and letting the wheels and prop spin up is equivalent to pushing the cart up to wind speed on the ground (or, if you are picky, to lowering it from a vehicle moving at wind speed and letting the wheels and prop spin up).

In my model, that process it expends energy from the road's motor, that becomes the KE at its final velocity.

Right. And on the road, the acceleration would take energy from the wind. The situations are identical. The treadmill test assumes acceleration to at or near wind speed, but that is the less interesting part of the cart's performance.

You don't see the need for this, because the cart just hangs around where it is put. That is a spurious artifact, that produces a confounding case. Correcting that friction, as in my model, will see is go back where it belongs. Test it.

You need to be more clear about what you mean here. Are you talking about friction of the wheels? Do you really believe that the cart on the treadmill has friction-free wheels? If so, how does it advance on the treadmill?

In any case, you must expect that the same thing would happen for the cart on the ground. That is, if we pushed it to wind speed, we would be creating a "spurious artifact" and creating a "confounding case".

Assuming instantaneous "windspeed" violates Newtonian physics. Models must include the influence of their operators.
You can't readjust your frame. That is how it is. All the translation are 'done'

Wind speed is not "assumed", it is forced. Again, placing the cart on the treadmill at wind speed is equivalent to pushing the cart up to wind speed on the road.

If you make a computer model using the same data, won't that cause some mathematical headaches?

A computer model would involve the surface, air, and cart, since those are the only things that are interacting.

 

[mender]

Spork, Humber's theory of operation is as follows:

"Humber is talking about the friction between the belt and the cart's drive wheels. He maintains that the wheels are slipping, resulting in a very delicate balance that supposedly keeps the cart in an "energy well". He also claims the lack of KE in either direction as witnessed by the "groundside observer" is what keeps the cart from moving, because the cart would need to gain KE in order to move, thus the slipping of the wheels to prevent that gain. A perturbation as demonstrated by the spork poking only disturbs that balance momentarily, and if the treadmill was longer, the cart would return to the original position unaided. A flywheel would serve the exact same purpose as the propeller, and in fact the propeller can be reversed without changing the results of the treadmill test."

He thinks that KE is an absolute, keyed to the earth, and that the only way to have the cart accurately modeled is to have the cart moving according to the ground at 10 mph. (Yet he laughs at the treadmill in a van that could be shown to do exactly that). He claims that the cart, as a result of being placed in the middle of the KE well with zero motion relative to the ground and therefore zero KE relative to the ground, cannot pull itself out of that zero KE condition and has an inherent balance as a result.

He also thinks that because of that, a tether would cause the cart to develop a force which would show on the scale in a positive feedback loop. According to his theory, if the tether was slack and the cart was in the middle of the belt, pulling on the tether will not disturb the cart from that position but will show a force on the tether directly in response to the pull on the tether. In other words, it will act like an object anchored to the earth to a certain extent.

To achieve this balancing act, the wheels must slip on the treadmill surface. To move the cart forward on the belt, the wheels must slip more so that the propulsive force from the prop has less counterforce to work against. Conversely, if the wheels slip less and grip the surface better, there will be more force moving the cart with the belt than the prop can compensate for, and the cart will move back on the belt.

So the whole premise is that the treadmill test has been cleverly set up to achieve the correct amount of slipping so that the cart can't gain KE relative to the ground in either direction, therefore it will maintain a steady state position on the treadmill for as long as the treadmill will run. This however proves nothing about actual travel along the ground because the cart has zero KE in relation to the ground, which Humber perceives as an absolute.

He thinks that because KE is stated as 1/2 mv2, the force required to move the cart is a function of the square of the speed change, when in actuality Newton states that F=MA, not velocity.

He proclaims that his view reflects Newtonian physics and indisputable, when in fact it is pre-Newtonian physics, the very thing he is attributing to all others. Fortunately, the history of physics and the very laws as stated by Newton prove that wrong.

Spork, I proposed a couple of tests based on Humber's theory of operation:

You still think the cart wheels are slipping on the belt. That should be the test you're asking for, whether adding weight to the drive wheels changes the net force acting on the cart.

Here goes: level the treadmill. Attach a scale via a tether to the cart exactly parallel to the treadmill surface (don't want to add any extra issues) and run the treadmill at 10 mph. Measure the forward pulling force. Place a weight equal to that of the cart over the drive wheels and retest.

For the second part, start with the cart in its original configuration. Baseline the pulling force. Spray WD-40 on the treadmill surface to reduce the friction. Record the results.

Or just get an optical tachometer and measure the drive wheels rpm and the prop rpm and confirm that the drive wheels don't slip.

Well, Humber? Will you ignore this post as well? I'm trying to help.

His secondary claim that the cart responds to a load as supplied by the tether can be tested as well.

His tertiary claim that the cart will not change position while the treadmill is tilted can be tested at the same time.

I hope that I've been able to clearly describe the essence of Humber's claims. With this in mind, I can think of several ways to test his theory. I'll leave that up to you and JB to devise mutually agreeable tests (again, hopefully) that you might be willing to conduct on your cart.

One more note, maybe this quote explaining the failings of the KE view from the site that I linked earlier will help explain Humber's reluctance to go beyond the kinetic energy argument:

"The ability of stress to amplify force is even more mysterious, regardless of the definition of energy. Since force is interchangeable with motion, amplifying force does not conserve energy. The force-distance analysis creates the appearance of amplified force not amplifying energy, because there is a mathematical relationship between the symbols. But the symbols (½mv² and Fs) are meaningless. Their absence of a relationship to objective reality immunizes them from contradictions with it, even with such mysterious complexities as force amplification."

 

[tsig]

Your reality must not be very convincing if you're not willing to rely on it and accept a wager against another's faith.

Your cart must be not too convincing since you have to pay people to see it.

 

[tsig]

Tsig:
>I would just wait for the power to fail.

And until then you would be unable to tell the difference -- just as our cart can't tell until the power fails.

Thanks for acknowledging the inability to tell the difference. You have demonstrated a clear ability to recognize that a treadmill is a fine way to generate "wind".

JB

Thanks for adding all the words I never said.

Arguing with your self and losing the argument is sad.

 

[Dan O.]

Nice try, and a dishonest one. I told Mender that a tether will upset the balance. And I also made the same remark to you concerning Ynot's tether.

No, the challenge is to increase the friction to the wheel only.

I described the behavior of the cart in my world and how it can be tested. If you don't like my test, specify your own. Tell us exactly how to test your theory. What result would indicate success, what result would indicate failure. Put up a wager to make performing the test worthwhile.


Humber is now on selective ignore. I will only respond to his posts concerning real testing.

 

[Crispy Duck]

I thought I'd pile in here, as it seems that everyone else has. One insight I had that helped, and that may not have been mentioned yet (I haven't read the whole thread, obviously), relates to the ice-boat case.

I don't know anything about ice-boats, but it has been stated here several times that ice-boats can tack downwind with a downwind velocity component greater than that of the wind. This sounds unlikely at first, but eventually I realised that in this situation, the ice-boat is actually tacking *into* a net *headwind*. We all know that boats of all types can tack into a headwind, so it's really not remarkable that an iceboat could go downwind so fast that it's actually tacking into a headwind.

I would be interested to know if iceboat sailors have to re-trim the sail significantly as they transition from net-downwind to net-upwind, or whether the required trim changes smoothly as the boat accelerates.

Anyway, HTH.

 

[Modified]

I would be interested to know if iceboat sailors have to re-trim the sail significantly as they transition from net-downwind to net-upwind, or whether the required trim changes smoothly as the boat accelerates.

I would guess that they could choose a sail configuration and direction such that no changes would be necessary to accelerate from zero to beyond wind speed in the downwind direction, though acceleration and top speed would be far from optimal in that configuration.

 

[ThinAirDesigns]

Thanks for adding all the words I never said.

What you have been unable to say has been very powerful -- a way to tell the difference between wind on a treadmill and the 'real world'.

JB

 

[spork]

I would guess that they could choose a sail configuration and direction such that no changes would be necessary to accelerate from zero to beyond wind speed in the downwind direction, though acceleration and top speed would be far from optimal in that configuration.

That's correct. They could in fact trim for max speed and start from a dead stop - it would just take longer to get their.

 

[ThinAirDesigns]

Me:

Really, does it advance slower? Does it just *look* tired on the level?

The small increase that you see in velocity, is not evidence of greater than windspeed travel, but an artifact that is dependent upon the angle of the treadmill. The time is sits there is of no consequence.

That doesn't answer the my question. Are you saying that it advances *faster* on an incline? Are you saying that it can't advance at all on the level?

Stop with the jibberish and make a clear statement: You claim that it doesn't perform as well on the level compared to an incline. Tell me exactly how the cart behaves *differently* in the incline vs level test.

JB

 

[humber]

d

Models have nothing to do with my remark. If you can state, without blushing, that the very relativity of inertial frames makes them absolute, you do not understand what you are talking about.

Not me, H'ethetheth. My blushing or not, makes no difference. Accept that.
There is no need to consider inertial frames. Nobody is traveling fast enough in this case, to make a difference. GPS satellites are doing so, and need to have their clocks adjusted, now and again. I do know that.
Now, how wrong could I be? How can you let what tiny differences that could exist, allow you to accept the enormous change that traveling without KE, or power source, or whatever represents? You worry about me ignoring Galileo? Tsig managed to get Spork to say that bullets would not kill him or something, because they had no KE. That's the Matrix, not realiity.
Newton' laws are a subset of other laws, but they still need to be addressed. They are extended by Einstein, not supplanted.

Yes. However, the realisation that objects are not reference frames is not interesting or in any way pertinent to the discussion. I think we can all agree on that. What is relevant to the discussion, is that you seem to think that reference frames are instruments of deception that lead to the false conclusion that this cart works.

I doubt that it is your deception, though. Mistakes are made, but there comes a point where that cannot be what is sustaining the ideas. I went to great pains to avoid saying that it was a fraud. Poster Marcus asked me, personally, were these ideas accepted by science? I said that in my opinion, no, but that I could not say otherwise. Spork posted some lies about Prof Whiteman, so I the asked the professor to clarify, that was my word. His answer was unpretentious, and quite in keeping with my experience with TAD.
He is highly qualified individual. His opinion counts, and his example is used to denigrate the entire profession, and science itself. Also-rans, do not get to do that, for their own amusement.
That is a side matter. The model is wrong, and cannot explain the cart, or lend support to the ideas that are attributed to it. The cart is not original in design by any means, but may be given a new coat of paint, to make it look so. You fill in the gaps. Look at the techniques employed against all who do not accept the word of Spork.

From what I've read, Newton thought that if such a frame should be defined, this "mother of all reference frames" would be at rest relative to the fixed(!) stars. For some time now, physicists realize that the stars are in fact not fixed, and therefore such a frame cannot be defined, nor was it ever necessary. All inertial reference frames are equivalent. They are decidedly not equal though.

Newton thought a lot of things. He wrote millions of words on alchemy, trying to convert base metals to gold. He hated Robert Hookes, and Leibniz.
It is not Newton, but the laws he bequeathed, to be used intelligently, and not as a stamp of approval, like Einstein. Poor Einstein, adopted by every charlatan from quack medicine to Scientology.

Indeed, and I'm not about to. It's just that the things you say about reference frames can really only be said in earnest by someone who isn't quite familiar with them. Your use of the term is muddled; sometimes imprecise, sometimes incorrect.

Muddled? I should think so. Do you not take into account the canards and sheer rhetorical BS I need to defeat to even get a word in without deliberate distortion? Do you want to start a discussion on the role of the observer? Are you a dualist or a naturalist? Dennett or Chopra? Forget it, not necessary. Obfuscation to support pipe dreams.

I am not responsible for the fact that a hammer has been needed to crack a walnut.

Now, I'm honestly trying to understand your position, so could you help me out here?

There is no secret to my "position", H'ethetheth.
To even consider the place that ideas would have, they first have to be relevant, but even if I do that in this case, there is nothing to be gained.
The failure of the model is not the failure of science's ideas, but the very treadmill concept. There is a list as long as your arm.
The first I have told you. The assumption is made that the differential velocity at windspeed is zero. OK, a given, but there is another case, that of a still object in still air. The two cases are likened only by this similarity!
It has zero differential, so it is called windspeed, rather than not moving.

Now, the model should not let you do that, not allow that error. If you make a mathematical model, the error is quite obvious. No KE, no motion, that can't be windspeed, but the cart simply balances, skimming the surface of the belt. Why, because the propeller is driving still air. Not the same as real wind.
A hits B.... When Dan_O asks me to do the calculations for both cases, he is not using real examples, but models. The car and the person are reduced to the quantities m and v. Well, of course they will be the same, the equations guarantee it. Real objects are complex, and don't behave that way. There is a mountain of detailed equations to describe that complex interaction. Simplify them and the result is less accurate, take it too far to reductio absurdum, and that's what you get.

Is it your understanding that the wind we say is generated by the treadmill is just the air dragged along by the surface of the belt by viscous friction?

Yes. That is correct.
Wind does not have only velocity. It has pressure for example. Wind has lower pressure. Can that be left out? If included, it would allow the room air to rush in and make a wind.

This is part of an incomplete post.

The red lines are power flow. In the treadmill, it goes nowhere into still air. There is no exchange mechanism for the belts energy to flow. The smaller drawings are the "viscous drags" in each case. That is all the wind that is modelled. The "other" wind, is when the cart is dragged by the belt through the air, that is NOT the same thing, and highly dependent upon the friction of that object to the belt. Not like real wind, at all. No friction, no wind.
That is one problem. The other problem is that there is no load for the propellor because the cart is stationary. The propellor cannot be forced to do work.
Try this: http://web.mit.edu/drela/Public/web/qprop/motorprop.pdf

Lots of things. You will need to resolve what is relevant and what is not. Everything is in this thread, the balance mechanism...
Spork's only response it to cat call and suggest that I am a virgin.
Think about the source of your information, H'ethetheth. It should not be me, OR Spork.

 

[Christian Klippel]

The other problem is that there is no load for the propellor because the cart is stationary. The propellor cannot be forced to do work.

Wow, now we know that in the humberverse, propeller driven airplanes (or anything else driven by prop) are just impossible. Because they would have no load when the object they are attached to is stationary. And we can even connect the biggest motor to the prop but it wouldn't help, since the prop can not be forced to do work.

Wow, really.

I'm wondering how propeller based airplanes and other vehicles are able to start moving. You know, usually the airplane stands still, passenger get in, motor is turned on, prop spins, plane starts to accelerate and eventually lifts of once the speed is high enough. Really, how do they do that, if according to humber that isn't possible at all?

Also, hove comes that my stationary fan blows wind onto me, and requires power to do that? In the humberverse, it would have no load, so it wouldn't need a motor to spin. But then, even with the motor it wouldn't blow in the humberverse, because the motor can not force the prop to do work.

I'm wondering if in the humberverse at least jet-engine based airplanes would work? Could rockets lift of in the humberverse?

Man, this dude is just so ridiculous, it isn't fun anymore.