Merged DDWFTTW in a “Real” Wind

[Dr. Keith]

As a small time inventor myself, I have had many people, mostly in construction trades, tell me that something I was suggesting couldn't be done. If it what something I cared much about, I would go ahead and build it. After that, when they could see it; touch it; examine it...the debate was over. Some admiration was often expressed.

I can't imagine the frustration of having some of them continue to argue against the item and its concept after the fact.
Hence, I am empathetic to the occasional short fuses here, especially considering how long it has gone on. Still, I wish it would stop, and we could get back to some fascinating physics.

I'm not an inventor, but I work with them every day so I can certainly empathize with what you are saying here.

I have had several clients approach businesses with ideas that could improve their products only to be turned away with a curt "that won't work." Through some perseverance several have proven both the science and marketability of those ideas and often sold them to the very people who rejected them.

I have also seen more than my share of PM or over-unity ideas and had to find ways to avoid being involved. I feel I have a good eye for this sort of thing and yet the BB was very eye opening. I love counter-intuitive ideas and it still took an embarrassingly long time to finally grasp.

 

[humber]

Oh, I'll tell you mine - I don't have any. There. Job done.

Your turn.

I already knew that, so it changes nothing, except that if you did, it would be shameful. People acquire or don't acquire qualifications for all sorts of reasons. From not having the opportunity, to having too much.

Oh no, you doin't get to use the sciencey type language without laying down your credentials first. Tell me what your degree is in and where you got it, then I'll decipher your sciencey language. I may need help, as I'm an ignoramus without qualifications, but I can find help if I need it, I assure you.

That is inane. Where necessary, I provide links, that may or may not be the source of my knowledge. You can read them too, or something from somewhere else. It would no take long, even at the simple level to learn that balloons can' travel at WS, and you should be happy that they don't. Chaos, literally, would ensue as a consequence.

Actually, yes. If you held some sort of postgrad qualification in aerodynamics or a smilar field and had published papers that had survived rigorous peer review, then I'd sit down and try and find the holes in the thought experiments that you have so often failed to point out.
So, what did you study, what did you get and where did you get it, Humber?

Oh, that's not possible. If I spelled that out, it would uniquely identify me.

 

[3point14]

Oh, that's not possible. If I spelled that out, it would uniquely identify me.

You have no qualifications.

You have no understanding of aerodynamics

You have no bottle.

You certainly have no understanding of frames of reference, this has been shown time and again.

You are, I'm afraid, Humber, a liar. I don't think that you're clever enough to understand what's going on with the cart (I am) and you're certainly not intelligent enough to get anything you write passed peer review.

I just can't work out if you know it or not.

 

[humber]

This is an interesting claim. Can you expand on what you think it means?

ETA The second sentence, that is. The first is entirely clear, thanks.

F=ma, is the founding Newtonian equation. Perverse application of inertial frames of reference, allows that to be ignored when making claims, by dint of mere dismissal; like WS balloons etc. It's a handy marketing tool for peddling nonsense, in the same way that over-unity people ignore losses by assuming they are not there, or use the euphemism "can be made arbitrarily low"

 

[Jack by the hedge]

F=ma, is the founding Newtonian equation. Perverse application of inertial frames of reference, allows that to be ignored when making claims, by dint of mere dismissal; like WS balloons etc. It's a handy marketing tool for peddling nonsense, in the same way that over-unity people ignore losses by assuming they are not there, or use the euphemism "can be made arbitrarily low"

Hmmmm. Can you try again?

Maybe you could just narrow down what precisely you meant by "When it does...".

I had assumed you meant When the wind transfers momentum by accelerating... I suppose it's also possible you meant the opposite - if the wind could transfer momentum without accelerating... - though I can't glean which you meant from your response.

 

[Llyricist]

This is an interesting claim. Can you expand on what you think it means?

ETA The second sentence, that is. The first is entirely clear, thanks.

You will find most of his "sciency" postings appear no better than the output of a random PoMo generator adapted for physics. In fact, jduffy developed one and has posted the outputs here and elsewhere, and humber has actually taken it seriously enough to argue with it.

 

[Jack by the hedge]

You will find most of his "sciency" postings appear no better than the output of a random PoMo generator adapted for physics. In fact, jduffy developed one and has posted the outputs here and elsewhere, and humber has actually taken it seriously enough to argue with it.

There is a familiar non sequitur aspect to the latest post.

"F=ma" is a good start, but "Perverse application of inertial frames of reference, allows that to be ignored when making claims, by dint of mere dismissal" makes no sense. Relative velocity will vary if you change your frame of reference, but acceleration will not. So you can't make acceleration vanish by "perverse" selection of a frame of reference. I struggle to imagine what claim he has in mind which merely dismisses Newton's 2nd law. Perhaps an example would help. He still hasn't condescended to explain the secret science which proves it impossible for a balloon to travel at windspeed, so that part defies analysis.

 

[CORed]

I already knew that, so it changes nothing, except that if you did, it would be shameful. People acquire or don't acquire qualifications for all sorts of reasons. From not having the opportunity, to having too much.


That is inane. Where necessary, I provide links, that may or may not be the source of my knowledge. You can read them too, or something from somewhere else. It would no take long, even at the simple level to learn that balloons can' travel at WS, and you should be happy that they don't. Chaos, literally, would ensue as a consequence.


Oh, that's not possible. If I spelled that out, it would uniquely identify me.

Curiously, humber has provided no links that support his contention that balloons can't reach wind speed. As with many things, he's provided a few that he says support it, but actually don't.

I will concede that it's also hard to find any reference that says they do. This most likely because, to anybody but humber, it's so obvious that nobody ever thought it necessary to explicitly state it.

 

[Skwinty]

I will concede that it's also hard to find any reference that says they do.

Because it's as close as dammit

 

[CORed]

I already knew that, so it changes nothing, except that if you did, it would be shameful. People acquire or don't acquire qualifications for all sorts of reasons. From not having the opportunity, to having too much.


That is inane. Where necessary, I provide links, that may or may not be the source of my knowledge.

And that may or may not support your claims. Usually not.

You can read them too, or something from somewhere else. It would no take long, even at the simple level to learn that balloons can' travel at WS, and you should be happy that they don't. Chaos, literally, would ensue as a consequence.


Oh, that's not possible. If I spelled that out, it would uniquely identify me.

 

[ThinAirDesigns]

I will concede that it's also hard to find any reference that says they do. This most likely because, to anybody but humber, it's so obvious that nobody ever thought it necessary to explicitly state it.

Yes - most of us understand that if you hold a neutral bouyancy balloon still in a room full of still air and then release it, it will remain in place. This "it's right there where I left it" principle is discovered early in life by all those except the humbers of the world. No textbook needed.

JB

 

[CORed]

Yes - most of us understand that if you hold a neutral bouyancy balloon still in a room full of still air and then release it, it will remain in place. This "it's right there where I left it" principle is discovered early in life by all those except the humbers of the world. No textbook needed.

JB

It seems, as much of humber's nonsense does, to go back to humber's complete lack of understanding of frames of reference and relative motion. I don't think he sees a balloon in still air as being anything like a balloon drifting with the wind. In spite of his denials, he still seems to think that the earth has a magical influence, and that motion relative to the ground requires force. His claim in a recent post that he understands frames of reference is laughable. With nearly every post he makes, he shows that he has no such understanding whatsoever.

 

[ThinAirDesigns]

It seems, as much of humber's nonsense does, to go back to humber's complete lack of understanding of frames of reference and relative motion. I don't think he sees a balloon in still air as being anything like a balloon drifting with the wind. In spite of his denials, he still seems to think that the earth has a magical influence, and that motion relative to the ground requires force. His claim in a recent post that he understands frames of reference is laughable. With nearly every post he makes, he shows that he has no such understanding whatsoever.

You are exactly right in your assessment. It's impossible for him to learn about actual frames of reference because he believes he knows all there is to know already.

Textbooks DO say that a balloon with drift at the same speed as the wind because textbooks describe the equivalence of frames of reference ad nauseum and a balloon drifting the same speed as the wind is thus exactly the same as a balloon sitting still in the room.

If your understanding of frames is screwed (as Humber's is) you are simply screwed in entirety regarding this brainteaser.

JB

 

[Skwinty]

All the balloon needs is a set of wheels geared correctly to a propeller and it will match and exceed the windspeed.

 

[Modified]

I will concede that it's also hard to find any reference that says they do. This most likely because, to anybody but humber, it's so obvious that nobody ever thought it necessary to explicitly state it.

Of course, there are hundreds of references to helium balloons being used to measure wind speed. The fact that they travel at wind speed is generally assumed to be too obvious to the reader to mention. No formula or correction mechanism to compute wind speed from balloon speed is ever given, since none is needed. With a Google search you can find a few sites that do specifically say they travel at wind speed: http://www.barrygray.pwp.blueyonder.co.uk/Tutoring/BGasBal.html, http://atoc.colorado.edu/wxlab/pibalwinds/index.html, etc.

I'm sure you can find dozens of Physics texts with problems and solutions that assume the same, and probably even some that state it explicitly. It doesn't matter. No reference will satisfy humber. He will tell you those are simplifications or some such nonsense.

There are many times more references that state explicitly that a hot air balloon travels at exactly wind speed. Humber has dismissed that in his own mind because a hot air balloon "has an engine", though he has no explanation for how that engine would produce horizontal acceleration, always in exactly the right amount to counteract the "humber mystery ground-oriented drag force".

 

[Skwinty]

Quite frankly, I don't understand the argument.

For me, the only mysteries are:
1. How much faster than wind speed can it go?
2. What practical purpose will be served?

 

[humber]

Curiously, humber has provided no links that support his contention that balloons can't reach wind speed. As with many things, he's provided a few that he says support it, but actually don't.

I will concede that it's also hard to find any reference that says they do. This most likely because, to anybody but humber, it's so obvious that nobody ever thought it necessary to explicitly state it.

On the contrary. It has been known for several hundred years. Carteers do need to move into this Century, or at least the end of the 19th. For instance, D'Alembert's paradox...

"In fluid dynamics, D'Alembert's paradox is a contradiction reached in 1752 by French mathematician Jean le Rond d'Alembert.[1] D'Alembert proved that — for incompressible and inviscid potential flow — the drag force is zero on a body moving with constant velocity relative to the fluid.[2] Zero drag is in direct contradiction to the observation of substantial drag on bodies moving relative to fluids, such as air and water; especially at high velocities corresponding with high Reynolds numbers."

...has been solved. Yes, you are going to tell me that "it's about things moving relative to a fluid !!" and not the Fairytale land of windspeed.

1) His conclusion would show that the wind cannot drive a balloon.

2) That obviously contradiction, led to further theoretical and practical work, that showed where the problem lay.

3) The result of all the work, is the discovery of things that mean balloons will not get to WS.

Since that time, there has been no to need to express that they may or may not.

 

[humber]

Of course, there are hundreds of references to helium balloons being used to measure wind speed. The fact that they travel at wind speed is generally assumed to be too obvious to the reader to mention. No formula or correction mechanism to compute wind speed from balloon speed is ever given, since none is needed. With a Google search you can find a few sites that do specifically say they travel at wind speed: http://www.barrygray.pwp.blueyonder.co.uk/Tutoring/BGasBal.html, http://atoc.colorado.edu/wxlab/pibalwinds/index.html, etc.

I'm sure you can find dozens of Physics texts with problems and solutions that assume the same, and probably even some that state it explicitly. It doesn't matter. No reference will satisfy humber. He will tell you those are simplifications or some such nonsense.

There are many times more references that state explicitly that a hot air balloon travels at exactly wind speed. Humber has dismissed that in his own mind because a hot air balloon "has an engine", though he has no explanation for how that engine would produce horizontal acceleration, always in exactly the right amount to counteract the "humber mystery ground-oriented drag force".

Nice work. Not a jot of evidence for your claim, but direct support of what I said about weather balloons. They are designed to rise, because there is no real means of keeping them to a horizontal path.
Guess what happens to the vectorial speed, when the balloon rise AND travels horizontally?
The notions and claims which are offered in support this cart are adolescent at best.

 

[humber]

You are exactly right in your assessment. It's impossible for him to learn about actual frames of reference because he believes he knows all there is to know already.

Textbooks DO say that a balloon with drift at the same speed as the wind because textbooks describe the equivalence of frames of reference ad nauseum and a balloon drifting the same speed as the wind is thus exactly the same as a balloon sitting still in the room.

No they do not on both counts. FOR is not commonly found in general texts.

Text books also contain information about load cells, and how to avoid mechanical failure by appropriate design. Yet, TAD's attempts at load cell use was a total disaster, and mechanical failure repeated ad nauseum.

The problem is not in the texts, but the understanding of the presented information. It would be hard to find a more intellectually immature and literal interpretation, than has been taken in support of WS balloons.

If your understanding of frames is screwed (as Humber's is) you are simply screwed in entirety regarding this brainteaser.
JB

The presented brainteaser, is a no-brainer. Guess why?

 

[Modified]

Nice work. Not a jot of evidence for your claim, but direct support of what I said about weather balloons. They are designed to rise, because there is no real means of keeping them to a horizontal path.
Guess what happens to the vectorial speed, when the balloon rise AND travels horizontally?
The notions and claims which are offered in support this cart are adolescent at best.

I don't think you read the first reference:

There is no way of controlling the horizontal movement of a helium balloon at a constant height: it moves at the speed of the wind in the direction of the wind.

No mention of rising there, only "constant height". And why would a rising balloon match wind speed but one that had reached its maximum height not? Is there some minimum speed it must rise at in order to match wind speed? If it rises faster than that speed does it outpace the wind? As usual, when caught in one hole you begin digging a new one as a distraction.

Show me the method for computing wind speed from balloon speed other than horizontal distance divided by time. Since this is such a common problem, there must be a method described in meteorology textbooks and on meteorology websites, right? Why can't I find even the hint of such a method?