Down wind faster than the wind

[H'ethetheth]

Volgens mij, niet.

Volgens mij kunnen de meesten hier dat niet lezen.

 

[Christian Klippel]

Volgens mij kunnen de meesten hier dat niet lezen.

Probably true for the most here, but since i live quite close to the dutch border, i can at least understand it a bit. It's not too much different from german.

But it also seems that certain people here don't understand english either. Anyways, when his claim is that 0-2=0, it doesn't matter much what according to him is or is not.

Greetings,

Chris

 

[Marcus]

Ok, I'm game -- give me some "other explanations" for:

A: a device that will run indefinitely on a treadmill at *exactly* the speed of the wind while climbing a ~4.5degree incline.

B: Will run indefintely on a level treadmill at *exactly* the speed of the wind while generating enough thrust to tensioning a string held from behind.

C: Can be dragged down to below windspeed and will speed itself up to above windspeed as many times as one cares to drag it down.

I'm not talking about people who don't know physics here -- I'm asking for physics explanations/hyposthesis that fit what we DO know about the cart and it behaviors which could lead to our results, but not DDWFTTW.

I'm not trying to be pissy -- it truly would be a fun conversation to have. Certainly a lot more fun than what humber has presented lately.

Fire away.

JB

I don't know enough physics to provide intelligent conservation on these points, so I won't waste your time trying.

I do have one question. You mentioned that you have been discussing this on the physics forums. Do the actual physicists, rather than the armchair variety like myself, agree that these treadmill tests provide proof of your model?

 

[sol invictus]

I do have one question. You mentioned that you have been discussing this on the physics forums. Do the actual physicists, rather than the armchair variety like myself, agree that these treadmill tests provide proof of your model?

Yes.

 

[Marcus]

OK. Let's get this old saw out of the way. Are you aware of how many devices from the late 19th century claimed for this effect? Even Tesla had a go, but he was not so honest, anyway. The idea dead and buried. It's a dinosaur. Now apart from that, it would be of no consequence in this case.
Your car may have huge KE from orbiting the sun. Try an insurance claim upon the basis. Now if Dan_O wants to pay extra cover for this, please do, because premiums are increasing, so that helps everybody else. A fool and his money etc.

Now to answer the question. Two cars in the street, both wizzing around the sun. The only thing that matters, is not that, but the difference between them, which is zero. There, solved.

A cart on treadmill has virtually no difference in velocity between one sitting on the nearby ground. Conclusion. No difference. No need to measure the sun. That has all been taken care of, because all things are equally affected, AND they share a common history. Nature keeps pretty tight books, so we can be sure that all credit and debts have long been paid. Everything is the same. All views are the same. Get over it.

Okay, you seem to understand frames of reference. But I don't get why you think that an observer standing on the ground beside the treadmill is analogous to a person observing an outside test. It has been pointed out numerous times just on this page that you would have to be standing on the belt, which is movng relative to the cart. The other part of your post, credit, debts, books, ect. makes no sense. Frames are frames, history and nature are irrelevant.

 

[Marcus]

Yes.

In that case, further tests would be pointless. It does take a lot of the fun out of the thread though.

Okay, one more question: Are you going to publish these results in a peer reviewed journal, or perhaps just a general interest magazine, like Scientific American?

 

[ThinAirDesigns]

Okay, one more question: Are you going to publish these results in a peer reviewed journal, or perhaps just a general interest magazine, like Scientific American?

We are submitting -- they decide to publish or not based on a number of things, many of which have nothing to do with the physics.

We'll see.

JB

 

[jjcote]

I don't think there's much hope here, but...
Mr. Humber, consider:

Would you agree that the test is valid if it consists of a board track, with a 10 mph tailwind, on which the cart is quickly pushed up to 10 mph, and is then allowed to accelerate? The claim that I'll make is that the cart will accelerate smoothly (so that the chassis has a net headwind) for the length of the track, but that I might be able to arrange for only 85 feet of track.

If that's okay, then do you see any difference if we look up from the experiment and see that there is nearby scenery moving in arbitrary directions? Trees sliding along this way or that way, or what have you? There would be a steady 10 mph breeze blowing along the track, and the cart will be moving at 12 mph or so along the track, with a 2 mph headwind. As long as that's the case, do you agree that the experiment is valid?

And if so, is it okay to do this experiment on a dead calm day, by putting the board track on a railroad flatcar moving at 10 mph, starting the cart at the front of the car and having it run toward where the caboose would typically be?

Answer that, and we'll proceed from there. (I don't have any plans to actually set anything up on a train, this is just for purposes of illustration.)

 

[Dan O.]

I can't believe humber is as stupid as his posts suggest. Let's see how many planets he destroys in this test.


In situation A, we have a cart facing West traveling East to West at 10 m/s on the flat surface of a road and the air moving East to West at 10 m/s.

In situation B, we have a cart facing West on the flat surface a treadmill where the surface is moving West to East at 10 m/s in a room with still air.

For each situation:

1. What is the speed of the cart relative to the surface?
2. What is the speed of the air relative to the surface?
3. What is the speed of the air relative to the cart?

Referencing only the surface, the cart and the air, what difference exists between situation A and situation B?

 

[ThinAirDesigns]

JJ --- Noooooo!!!.

LOL

Welcome

JB

 

[Dan O.]

Welcome to our little forum jj. Have you figured out the "trick" with the cart on the treadmill yet?

 

[John Freestone]

They will never test this device under scrutiny.

Escrow.

FYI.
That long drive shaft acts as a torsion spring. When the propeller is turned by the wind from the front, some energy is lost as it retards the vehicle, but some is stored in that spring and returned. Not a lot but everything counts. Add to that the momentum of the propeller, and you have a nice little energy pump going. Perhaps it may even resonate.

Troll. Not even an interesting or witty troll.

I don't think there's much hope here, but...
Mr. Humber, consider

It does sound unlikely.

 

[ThinAirDesigns]

Welcome to our little forum jj. Have you figured out the "trick" with the cart on the treadmill yet?

JJ is a hang gliding buddy who has been onboard forever.

Sharp dude.

JB

 

[Dan O.]

JJ is a hang gliding buddy who has been onboard forever.

I knew that. I Googled him before posting.

 

[RossFW]

Oh dear,

Here I was thinking I'd joined a group of skeptics and crtiical thinkers.

The little device moves forward on the tradmill because of momentum. it would (Obviously!!) not maintain forward motin on a flat surface.

As to the big one, someone mentioned the explanation but was ignored in all the zeal to demonstrate our mathmatical prowess and cohones

Some points-

1) It claims to achieve 23MPH into a 5-10MPH wind

2) Though no steering mechanism is obvious, it makes several course correction

3) There is a small bracket on the front wheel.

C'mon, folks- IT'S BEING TOWED!!!!

 

[humber]

Volgens mij kunnen de meesten hier dat niet lezen.

...of verstaan. Ja, sorry.

I had seen what was under your avatar, and that Christian lived in the Rhur valley, so it was aimed at him because of that, and suggesting that what he wrote made no sense to me, so "Dubble Dutch".

 

[Dan O.]

Oh dear,

Here I was thinking I'd joined a group of skeptics and crtiical thinkers.

You should read more of the thread before jumping to conclusions.



BTW, How to you keep airplanes from falling out of the sky on the underside of the world.

 

[Brian-M]

You are correct when you say Work = fxd, but Power = WorkxTime.

Nope, wrong again. Power = Work / Time.
You've got it back-to-front.

http://en.wikipedia.org/wiki/Power_(physics)

Your cart will need the same amount of power to get it to 2V as a 1/1 cart.

Nope. It can get to 2V with the same power by taking twice as long.

However, the force is halved and the 'velocity' doubled, so it will take 4 times as long to get there. What takes 1s, for a 1/1 cart, will take 4s for a -1/2cart.

Nope. You're assuming that the cart is being pushed with the same force as the 1/1 cart. Because the 1/2 cart pushes back on the medium pushing it, it ends up being supplied with twice the force. This means it accelerates with the same force as a 1/1 cart (ignoring the many inefficiencies involved).

It takes twice the time to reach twice the speed.

So they are the same, I am afraid. Overall efficiency is likely to be lower than a 1/1.

Do you mean that efficiency will be less than 1, or that efficiency will be less than a 1/1 cart? Either way, so what? Nobody's claiming that this cart will be particularly efficient.

How do you keep the cart's velocity constant? An incremental change of the conveyer will always produce twice that at the cart. In practice, friction will determine the terminal velocity of the cart, and so that of the conveyer.

Funny how you ask a question in once sentence, answer yourself in the next and throw in a non-sequiter in the third.

The maximum velocity of the cart is twice the belt speed. Problems with friction, such as wasted energy or loss of traction will reduce the final velocity of the cart, but as long as it's efficient enough and has good enough traction, it will travel faster than the medium pushing it.

Anyway, it appears that the only simple option is to let the cart run a little faster than wanted, and then let it coast a little below that, and then repeat. The average will be the desired speed. How do you do that? Apply a force, stop, and repeat.
This is why I remarked about the fingers of the operator in the video of the skateboard device. That is what he is doing.

Your device would end up being driven for quite a while on the momentum of the rotating mass of the wheels (which also reduce the acceleration). Just like Goodman's cart, though it is the wind, the propeller and the wheels, that determine when to store, and when it is better to trade for velocity.

Wait... So now you're saying you believe that it is not possible for this cart to indefintely maintain a velocity greater than the medium pushing it? Last time I asked, you made it very clear that you did.

What made you flip-flop again? You do this very often, without warning, explaination or logical consistency.

 

[humber]

I don't think there's much hope here, but...
Mr. Humber, consider:

Would you agree that the test is valid if it consists of a board track, with a 10 mph tailwind, on which the cart is quickly pushed up to 10 mph, and is then allowed to accelerate? The claim that I'll make is that the cart will accelerate smoothly (so that the chassis has a net headwind) for the length of the track, but that I might be able to arrange for only 85 feet of track.

If you mean, jjcote, that the cart is towed of pushed so that it is the same speed as the tailwind, then, yes. I have suggested that, but in a controlled air flow.

If that's okay, then do you see any difference if we look up from the experiment and see that there is nearby scenery moving in arbitrary directions? Trees sliding along this way or that way, or what have you? There would be a steady 10 mph breeze blowing along the track, and the cart will be moving at 12 mph or so along the track, with a 2 mph headwind. As long as that's the case, do you agree that the experiment is valid?

Just as a start I have to accept that all physical effects are a linear function of velocity. No, on that one, I am afraid.

And if so, is it okay to do this experiment on a dead calm day, by putting the board track on a railroad flatcar moving at 10 mph, starting the cart at the front of the car and having it run toward where the caboose would typically be?

Not equivalent, but a possible test, yes.


[/QUOTE]
Answer that, and we'll proceed from there. (I don't have any plans to actually set anything up on a train, this is just for purposes of illustration.)[/QUOTE]

Is this going to end up with the treadmill in an enclosed van?

 

[Brian-M]

The cart is stationary, so the forces are in balance, whether you like it or not.

Accelerating on a treadmill, in the opposite direction the treadmill is moving is not stationary.

It is not stationary relative to the treadmill.
It is not stationary relative to the room.
It is not stationary relative to the air.
It is not stationary relative to anything.

If it's velocity is changing, it is not stationary.

Spork and others have posted dozens of videos showing clearly that the cart moves along the treadmill, and yet you focus on the handfull of videos, where the treadmill has been deliberately tilted to balance the forces, to convince yourself that the forces acting on the cart must always be in balance.

This is a deliberate act of self-delusion. Just viewing any of the videos where the treadmill is not tilted clearly shows that the cart does not remain stationary.

You've repeated the lie about the cart being stationary endlessly throughout the thread, as if by saying it often enough will somehow make it true.

It won't.

Wake up to yourself and actually look at what is happening.

Do you really think you can convince us that the cart is remaining stationary when we can see it moving along the belt? Do you really expect us to believe that it is in balance, when the cart recovers lost velocity after been repeatedly pushed backwards?

Do you really expect us to believe that someone incapable of comprehending the basic principles of equivalency happens to be the only one to truly understand the underlying physics of the cart?

I hope you don't, because if you do, then the only person you're fooling is yourself.