Split Thread The validity of classical physics (split from: DWFTTW)

[humber]

What had to do with me? And why would it be flattering? You're not making sense, as usual.

Not to you.

 

[Christian Klippel]

Not to you.

Not to anyone here.

 

[humber]

Not to anyone here.

So Christian, you say that when you are on the belt. the cart is moving away from you at beltspeed "from you frame of reference"? No it isn't.
It is the same distance away from you, as when you stepped on the belt.

Try this. Step on the belt and freeze time. Where is the cart? Let's say 1 meter ahead of you. You say the belt is "really" infinitely long, so let's do that. You want to improve your boundary conditions, so let's make the belt infinitely wide too. What do you see? An infinite plane of black rubber. If there is no motion between the belt and your feet, there can be no motion between the cart and the belt. Windspeed has 'gone'.

Where is the cart? Always 1 meter in front of you. It must be, it is in the same frame as you.

 

[spacediver]

that's not an answer. I've provided a situation, and I'm asking you if the beachball's motion in the air is at all affected by the movement of the plane, even though it's going at a constant velocity. Importantly, the beachball is thrown AFTER the plane has accelerated to the constant velocity.

just incase you missed this, humber

 

[Brian-M]

This is not an important point, and I am willing to concede defeat, but I cannot see how I am wrong.

[qimg]http://www.internationalskeptics.com/forums/attachment.php?attachmentid=12662&stc=1&d=1231651083[/qimg]

This is real wind. The laminar flow is a stack of layers, that slide over on another, yet they always move forward in the direction of the wind.

If the hand is placed so the wind is on the back of the hand, for speeds less than windspeed, I cannot see how the force can ever be felt upon the palm of the hand, if for no other reason than the hand would shield it.

As soon as the same observer moves up the belt, he will immediately feel the laminar flow upon his palm.

It's quite easy to show you how you are wrong. (The trouble is convincing you to accept the explanation.)

Take an observer, standing on the road with his palms facing forward and the wind at his back.

The wind is blowing at 10mph.

He lowers his hand to a height where, due to laminar flow, the wind on the back of his hand is only 7mph.

Now he moves forwards at 8mph.

He is still travelling at 2mph slower than the wind, but his hand is moving at 1mph faster than the laminar flow.

Consequently, he feels a 1mph headwind against the palm of his hand. That's how he can feel wind against the palm of his hand. He may be travelling slower than the wind, but he is travelling faster than the laminar flow.

If he tries the same experiment on a treadmill, on a windless day, he'll get exactly the same results.

Your "hand test" fails completely Humber.

You refuse to acknowledge that, yet it is patently obvious, and has being mentioned many times over the course of this thread.
The laminar flow is dragged back by the belt, in the opposite direction to the supposed tailwind.

You enjoy ignoring inconvenient facts, don't you? The air dragged back by the treadmill will still be travelling slower than the belt. Relative to the belt, this means the laminar flow is still travelling in the same direction as the wind, just slower. This is exactly the same as on a road in a "real" wind. There is no difference.

That is not enough to make the case valid. The power source is not correct.
The road is not the power source for the real wind.
The wind on the belt does not exist in any physical sense until the object on the belt is moving with the belt. It is quite clear that the force produced by this wind can be no greater than can be sustained by the friction to the belt. Friction to the belt is related to the rolling resistance and gravity. Therefore, the force of the wind is directly related to the force of gravity. That is not the case for real wind.

So, in other words, with insufficient friction an object on the belt would slide on the belt, so that there was less kinetic energy between the object and the air?

It's exactly the same as you would see in the "real" wind. With insufficient friction an object on the road would slide on the road, so that there would be less kinetic energy between the object and the air.

When you say "It is quite clear that the force produced by this wind can be no greater than can be sustained by the friction to the belt. Friction to the belt is related to the rolling resistance and gravity." you could easily substitute "road" for belt without being any less correct.

Both situations are identical.

That means that you can change the physical aspects of those frames. You can't make the road the power source for the wind, because that is not so in nature.

It is so in nature.

Several of us have pointed out to you that the earth itself is rotating.

The "real" wind may be moving relative to the average motion of the earth, but then again, so is the road. To say that the road is still and the air is moving is purely a convention of convenience.

It would be equally valid to say that the road is moving and the air is still, which means that it would be equally valid to say that it is the road that is powering the cart, and not the wind.

I pointed out repeatedly on the other thread that the cart is much easier to understand if you think of the air as still and the road as moving along under the cart.

Equivalency does not allow you to declare frames invalid, or dictate which observer is "correct". You are violating the idea, yet I am holding to it.

All frames are equally valid. The same situation in different frames achieves the same results.

Using beltspeed for the frame of reference, the cart on a treadmill in an enclosed space is exactly the same situation as a cart on road with tailwind.

The only one declaring different frames of reference invalid here is you.

Also, I have just found my old friend, the differential Doppler radar. It's got a digital display 'n' all. Seems that I can tell.

Okay, stand on a road and point the radar at someone standing nearby. The radar should read 0mph.
Now stand on a treadmill and point the radar at someone else standing on the same treadmill. The radar should read 0mph.
No matter how fast the treadmill is moving, the radar will always read 0mph.

Standing on a moving treadmill is the same as standing on the road in the wind. Your radar test fails too.

Of course, you could stand on the treadmill and point the radar at objects that aren't also on the treadmill, but that would be the same as standing on the road and pointing the radar at moving objects.

Also, there is a distinction between not knowing there is a difference, and there actually being no difference. An argument from ignorance. What a surprise.

There an even bigger distinction between not knowing that there is a difference, and knowing that there really is no difference. Your insistence that there must be an unknown difference regardless of the logic presented to the contrary is an argument from personal incredulity. What a surprise.

How does a mass flow that is going forward become reversed when you put a cart in it? Laminar flow moves somewhat slower, but not backwards. If a car driving parallel to you slows, is it going backwards? May be to you, if you want to think in such a way, but not w.r.t the road. The cart and laminar flow have the road in common, don't they? You have to agree.

Obviously, I don't have to agree. Do you actually enjoy being wrong?
For the ten-thousandth time, velocity is relative.

Relative to the belt, the laminar flow is moving slower than the tailwind, but not backwards. Relative to the cart moving at belt speed, the laminar flow is moving backwards.

Relative to the road, the laminar flow is moving slower than the tailwind, but not backwards. Relative to the cart moving at wind speed, the laminar flow is moving backwards.

Relative to you, the slower car is moving backwards. The physics of this is not affected by your relative velocity to the ground.

ETA:
Isn't the belt already going backwards? You are not counting your chickens twice are you?
In the wind ,the laminar flow may be thought of as coupled to the road, but not the wind above it. It seems that that the "wind" that quite clearly (vid #7) moves with the belt, moves in opposition to that upper wind.

If we're using belt-speed as the frame of reference, then no the belt is not moving backwards. It is, by the definition of our frame of reference, stationary. It's the air that is moving.

The original BMW shot I said was likely not to be representative of the real thing. A photographer's fantasy. The video confirmed what I said, and the means of staying it.
It works as I described. Why would you need a 300kph fan, when you could just turn up the beltspeed?

If they wanted to simulate driving at 300km/h in a 300km/h wind, they wouldn't need to turn the fan on. However, if they want to simulate driving on a windless day, then the air needs to be travelling at belt speed. That's what the fan is for, to cancel out the apparent wind caused by being on the treadmill.

The problem of the orange bothers me. When I move it either with the belt, or against the belt, it seems to gain KE w.r.t. the belt and ground by equal amounts. This too seems to be inconsistent with the operation of the current treadmill.

Do the math: Ke = M/2 * V ^2

As the formula is non-linear, and the relative velocity of the orange to the belt and ground is always different, it's impossible for the orange to gain Ke w.r.t. belt & ground by equal amounts.

 

[fredriks]

I don't get this thread at all. I understand that people argued with humber when he was derailing other treads but over 1000 posts in his own thread arguing complete nonsense like the following quote. What the reason to argue with someone that definitely don't want to learn, having a discussion and don't have a clue about the basic concepts that he is using.

So Christian, you say that when you are on the belt. the cart is moving away from you at beltspeed "from you frame of reference"? No it isn't.
It is the same distance away from you, as when you stepped on the belt.

Try this. Step on the belt and freeze time. Where is the cart? Let's say 1 meter ahead of you. You say the belt is "really" infinitely long, so let's do that. You want to improve your boundary conditions, so let's make the belt infinitely wide too. What do you see? An infinite plane of black rubber. If there is no motion between the belt and your feet, there can be no motion between the cart and the belt. Windspeed has 'gone'.

Where is the cart? Always 1 meter in front of you. It must be, it is in the same frame as you.

Humber, you show for probably the 1000 time that you don't have a clue about the meaning of reference frame.

 

[Christian Klippel]

So Christian, you say that when you are on the belt. the cart is moving away from you at beltspeed "from you frame of reference"? No it isn't.
It is the same distance away from you, as when you stepped on the belt.

If that would be true, then the cart would move backwards, _with_ the belt, _through_ the air. It is clearly visible that instead that cart remains staionary to the air, while the belt is moving.

When i would step on that belt, i would be moving along with it, so yes, the cart does move away from me.

Try this. Step on the belt and freeze time. Where is the cart? Let's say 1 meter ahead of you. You say the belt is "really" infinitely long, so let's do that. You want to improve your boundary conditions, so let's make the belt infinitely wide too. What do you see? An infinite plane of black rubber. If there is no motion between the belt and your feet, there can be no motion between the cart and the belt. Windspeed has 'gone'.

Dude, do you even recognize how stupid it is what you write? It is beyond any reality. Freezing time? Are you kidding me? Under that condition none of your shiny toys, that you like to bring up all the time, would work either. No radar gun, no accelerometer, no hand. Nothing. Freezing time means that absolutely everything stands still.

What do you try to achieve by posting such blatant stupidity here? Making yourself the laughing stock of the forum?

You can not make such statements and expect that people will take you serious. What you just posted is by far the dumbest, non-sensical thing you ever posted.

Where is the cart? Always 1 meter in front of you. It must be, it is in the same frame as you.

Of course it would, if time is stopped. But then, the same is true with _everything_ else in the whole damn universe. Really, you are getting out of the bounds of sanity here.

Man, freezing time to proof some nonsensical argument. Never saw any such compressed stupidity in a few lines, on any internet forum ever. Even the perpetual-motion/free-energy crackpots make way more sense than your posts.

And what the heck have my feet on the belt to do with the cart on the same belt? Exactly, nothing at all. In case you missed it, the cart has wheels. You know, these tiny little things that spin around. The ones that drive the prop. You know, W_H_E_E_L_S! These things here! Not these here!

Unless you glue them to the belt, they will do what wheels do: rotate around their axis. Do you grasp at least this simple concept?

This post of yours is really an insult on everyones intelligence, even on my cats intelligence.

Edit: Btw, no, the cart would not be in the same frame as me. It would only be if i glue it to my body, or if i would sit in it. What you just said that when i jump on the street, in front of any car, no car would ever hit me because it would be in the same frame as me. Frames of reference are not picture frames, in case you didn't know yet.

 

[Brian-M]

I do sometimes find facts to be disagreeable.

I've noticed that, but surely finding facts to be disagreeable is no reason to constantly disagree with them.

Take the cart, for example. Spork has posted numerous videos of the cart accelerating against the direction of the belt. When the cart's motion is arrested, and even reversed by spork pushing back on it with, appropriately, as spork, the cart regains it's lost velocity.

Ignoring all this, you focus on the one video where spork tilts the treadmill so the cart remains in place, and argue, against all reason and facts that the cart always remains stationary, and then build up fancy and absurd explainations as to why the cart always remains stationary when it's obvious to anyone who has seen the videos that it does not.

Your exaggerated confirmation bias denies reality to such a degree that it boarders on insanity.

So Christian, you say that when you are on the belt. the cart is moving away from you at beltspeed "from you frame of reference"? No it isn't.
It is the same distance away from you, as when you stepped on the belt.

Try this. Step on the belt and freeze time. Where is the cart? Let's say 1 meter ahead of you. You say the belt is "really" infinitely long, so let's do that. You want to improve your boundary conditions, so let's make the belt infinitely wide too. What do you see? An infinite plane of black rubber. If there is no motion between the belt and your feet, there can be no motion between the cart and the belt. Windspeed has 'gone'.

Where is the cart? Always 1 meter in front of you. It must be, it is in the same frame as you.

As I just pointed out, the videos, which I assume you've watched, clearly show the cart travelling relative to the belt, in the opposite direction to the belt's relative velocity to the ground. In fact, even if the cart was "hovering" in place, as you claim, it would still be moving relative to the belt.

If the cart is moving relative to the belt then your claim that there "there can be no motion between the cart and the belt" if "If there is no motion between the belt and your feet" is clearly gibberish.

Well, I am trying to explain something that is to me rather obvious Brian-M.
That is a problem. But that is not all.
(1) The consequences of "bullet time" rivers. (No answer.)
(2) How about that you can't measure the KE, and that it looks exactly like it has near zero in all frames? (Unresolved at best.)
(3) If that's not true, how can the fork work? (No answer.)
(4) How is it that there is a difference in the behaviour of the wheels at windspeed? (ignored)
(5) How is it that Mender's experiments confirm what I said?
(6) He says he has to tune it to stay there! Not only does it support my contention, how is that related to the real road? Not at all.
(7) Or how the F1/BMW wind tunnel is not like a treadmill and has a stabilisor.

If you want me to address these points, describe the problem(s) in full. These condensed notes may make sense to you, but they don't make much sense to me.

Yes. I challenge you to show me where I have said that was not so. How many times have I told you that equivalence is just another way of saying that the world is Newtonian? When I do that, I am told that I am a flat-earther, but not Mr Feynman?
According to you, Feynman disagrees with Einstein who says that with an accelerometer, you can tell if you are moving. That is, accelerating.

First of all, moving is not the same thing as accellerating. Feynman's statment was about motion, not acceleration.

But seeing as you're the one who brought up the Einstien lift experiment in the first place, surely you should be aware that Einstein concluded that there was no way to tell if the lift really was accelerating through space at 1G, or if it was just sitting motionless on the surface of the earth?

In which case, both Einstein and Feynman disagree with you.

 

[Christian Klippel]

Spork,

can you please do me a favor? Put the cart on the treadmill, running, so that it stands still relative to the air. You know, the usual stuff.

When done, cane you please drop whatever you have at hand behind the cart, onto the running belt? Like a brick, or a teddy-bear, or whatever? And then video it and put it up on youtube?

But please do that without freezing time!

Thanks,

Chris

Edit: Heck, you might even use a orange as an object to drop behind the cart!

 

[Christian Klippel]

Hello fredriks,

...arguing complete nonsense like the following quote with someone that definitely don't want to learn or having a discussion and don't have a clue about the basic concepts that he is using.

you surely don't mean me, i guess, as being the one not wanting to learn and having no clue.

However, the wording you have chosen would say just that. Just replace the "with someone" with "from someone" and all is fine....

Greetings,

Chris

Edit: Of course my above remark is true for anyone else here arguing with him and does not only apply to me.

 

[Clive]

If they wanted to simulate driving at 300km/h in a 300km/h wind, they wouldn't need to turn the fan on. However, if they want to simulate driving on a windless day, then the air needs to be travelling at belt speed. That's what the fan is for, to cancel out the apparent wind caused by being on the treadmill.

A fairly minor matter in the big scheme of things, but I disagree with your first and last sentences in the above paragraph (from your long recent post to humber).

The first sentence is incorrect as written. A corrected version could be: "If they wanted to simulate driving at 300km/h in a 300km/h tailwind, they wouldn't need to use the fan, but if the wind was from any other direction or at a different speed then they would have to."

Perhaps I'm just not quite getting what you've said in the last sentence but I would replace that with something like: "The fan is there to generate the correct apparent wind felt by the car given the particular details of the real world situation being modelled." Alternatively, "The fan produces a wind relative to the moving belt that simulates the weather related wind (relative to the road) in the real world scenario."

 

[humber]

It's quite easy to show you how you are wrong. (The trouble is convincing you to accept the explanation.)
Take an observer, standing on the road with his palms facing forward and the wind at his back.
The wind is blowing at 10mph.
He lowers his hand to a height where, due to laminar flow, the wind on the back of his hand is only 7mph.
Now he moves forwards at 8mph.
He is still travelling at 2mph slower than the wind, but his hand is moving at 1mph faster than the laminar flow.
Consequently, he feels a 1mph headwind against the palm of his hand. That's how he can feel wind against the palm of his hand. He may be travelling slower than the wind, but he is travelling faster than the laminar flow.

You are confusing motion through airflow, with the flow. The laminar flow moves with the wind. The difference between the wind and flow is a constant 3mph. When you add speed to the windblown object, you add speed to the hand.

If he tries the same experiment on a treadmill, on a windless day, he'll get exactly the same results.
Your "hand test" fails completely Humber.

For the above reasons, the contraflow of the belt will corrupt the experiment.

You enjoy ignoring inconvenient facts, don't you? The air dragged back by the treadmill will still be travelling slower than the belt. Relative to the belt, this means the laminar flow is still travelling in the same direction as the wind, just slower. This is exactly the same as on a road in a "real" wind. There is no difference.

It is the wrong way, Brian-M

So, in other words, with insufficient friction an object on the belt would slide on the belt, so that there was less kinetic energy between the object and the air?
It's exactly the same as you would see in the "real" wind. With insufficient friction an object on the road would slide on the road, so that there would be less kinetic energy between the object and the air.

Real wind can move an object independently of friction to the road.

When you say "It is quite clear that the force produced by this wind can be no greater than can be sustained by the friction to the belt. Friction to the belt is related to the rolling resistance and gravity." you could easily substitute "road" for belt without being any less correct.
Both situations are identical.

No, I could not. In real wind, the propeller drives the wheels. This force will generates a ground reaction to the rear of the driving axle. That force and the friction do generated propel the vehicle's axle until friction should break due to excessive force or whatever. This is in no way like the static (rolling) friction to the belt. That is low. That is why we use wheels. Tyres allow the wheel to change shape. They adapt to the load. High or low rolling resistance according to load. This cannot happen on the belt, because there is no load, which is why there is no axle movement on the belt, whereas there is in reality.

It is so in nature.

Several of us have pointed out to you that the earth itself is rotating.

How do you know? I think you are a follower of Heliocentricism.
This thinking has no place in the treadmill. You can't ignore a huge error in favour of a minor influence.

The "real" wind may be moving relative to the average motion of the earth, but then again, so is the road. To say that the road is still and the air is moving is purely a convention of convenience.

That the real wind, is a source of power that blows over the road, is not a matter of convention.

It would be equally valid to say that the road is moving and the air is still, which means that it would be equally valid to say that it is the road that is powering the cart, and not the wind.

The belt is just a source of power. What of a car on the a road? If you put a real car on a running belt, but do not start the engine, do you think that is the same as a car on the road? If not, why do you think a propeller driven by a belt is like a propeller in real wind?
What's the difference Brian_M? In the real world, the wind drives the propeller directly, exchanging real energy and the load of the cart as it is propelled forward. The belt can only drive the propeller, via the friction too the belt. That limits the power doesn't it? To that force too is determined by gravity and friction, and to low to drive the cart, or only just a bit.

I pointed out repeatedly on the other thread that the cart is much easier to understand if you think of the air as still and the road as moving along under the cart.

Yes. That is comforting.

All frames are equally valid. The same situation in different frames achieves the same results.

Not on the treadmill Bryan-M. It's topsy-turvy because the cart is going the wrong way, while equivalence useage contains some "upsidedownism"

Using beltspeed for the frame of reference, the cart on a treadmill in an enclosed space is exactly the same situation as a cart on road with tailwind.

No way, Jose.

The only one declaring different frames of reference invalid here is you.
Okay, stand on a road and point the radar at someone standing nearby. The radar should read 0mph.
Now stand on a treadmill and point the radar at someone else standing on the same treadmill. The radar should read 0mph.
No matter how fast the treadmill is moving, the radar will always read 0mph.

Now, don't do any of that. Save yourself the trouble.
That is just information transfer, Brian-M.

Standing on a moving treadmill is the same as standing on the road in the wind. Your radar test fails too.

Back to prison.

Of course, you could stand on the treadmill and point the radar at objects that aren't also on the treadmill, but that would be the same as standing on the road and pointing the radar at moving objects.

Perhaps but I didn't read it. You are arguing from the assumption that the treadmill is already valid, again. Text book examples are rarely wrong.

There an even bigger distinction between not knowing that there is a difference, and knowing that there really is no difference.

Yes. It's called knowledge.

Your insistence that there must be an unknown difference regardless of the logic presented to the contrary is an argument from personal incredulity. What a surprise.

I don't think I said that. No, I don't think I could say that.
I say your information path is corrupted.

Obviously, I don't have to agree. Do you actually enj-oy being wrong?
For the ten-thousandth time, velocity is relative.

When are you going to take yes for an answer, Brian_M? It's not the theory it's the application that is in question. You presume too much. I don't see the world the way you do. I think of all things being in one "frame" but containing different amounts of KE as a dimension. Objects move incrementally, and so forth, there are no "interframes "at all.
I think of velocity as a dimension, force and acceleration too. That is why I think of the cart as being in force "well". I don't impose that view on you. Just that it your ideas be consistent ,and correctly applied.

Relative to the belt, the laminar flow is moving slower than the tailwind, but not backwards. Relative to the cart moving at belt speed, the laminar flow is moving backwards.
Relative to the road, the laminar flow is moving slower than the tailwind, but not backwards. Relative to the cart moving at wind speed, the laminar flow is moving backwards.
Relative to you, the slower car is moving backwards. The physics of this is not affected by your relative velocity to the ground.
If we're using belt-speed as the frame of reference, then no the belt is not moving backwards. It is, by the definition of our frame of reference, stationary. It's the air that is moving.

(1) There is no wind in the belt's frame of reference .

(2) As explained. Laminar flow is a flow. It does not make stops for photos.
On the treadmill there are two flows. They will always be distinguishable by the same test.
(3) Take a red and a blue smoke generator so as to colour belt and observer flows. Definitely not the same as real in wind. Do I win?

If they wanted to simulate driving at 300km/h in a 300km/h wind, they wouldn't need to turn the fan on.

Unlikely to install the belt or fan. The number of races conducted in 300kph tail or head winds, resides at zero.

However, if they want to simulate driving on a windless day, then the air needs to be travelling at belt speed. That's what the fan is for, to cancel out the apparent wind caused by being on the treadmill.

I still don't think they would install it. Actually, it's to simulate the headwind while driving at that speed. They are quite interested in going fast I have been told.

Do the math: Ke = M/2 * V ^2 NO!
As the formula is non-linear, and the relative velocity of the orange to the belt and ground is always different, it's impossible for the orange to gain Ke w.r.t. belt & ground by equal amounts.

If the belt is parallel to the floor, motion along the belt is the same as motion relative to the ground. "Beltspeed" is zero w.r.t the ground, so motion or velocity are to the 'left' or 'right' of that. Spinning on the belt is just like being held back a bit. I did to some oranges at the supermarket checkout last week. Quite, easy really. Bananas have potential.

Turning the belt off results in the same figures, it seems. Don't let anybody whisper 'windspeed' in your ear though, because then you will be at windspeed, but with the belt off.!

Bryan_M,
A belt in a windtunnel is not a road. Go outside to your car and put a belt under the car, but not the wheels. Turn it on. At work yet?
Put the car on the belt? Still at home I expect.

The car is held stationary because that minimizes the wind-speed they need to generate to test for high real-world speeds, but without actually moving the car, which is in fact necessary to a keep the car in the room?
If they can do that anyway, they may not need the wind! They also do not want to go backwards relative to that expensive wind.

The belt does not simulate the road, Brian-M, but the differential velocity between, say, the underbelly, and the road at the speed the vehicle would be doing if it were traveling. It's a simulation of the surface of the road, not the road itself. It is figurative. It can be made of many types of material, as long as the interaction with the wind (to interact with the laminar flow) is accurate. There is no power transfer requirement, because it's held in place, and it need only power the laminar flow.
It's not the physical embodiment that is important, but the knowledge that it transfers, This, with a relatively small amount of energy from the belt, makes the air near the belt behave like the real thing. When that air is added to 'ordinary' wind from the fan, the two 'mesh' to produce a good simulation. Just like the correct use of relative velocities, would suggest.
That is what is simulated; the aerodynamics, not the motion.
One day, when the science is very good, the information 'embodied' in the simulated road surface, will become numbers in a computer, and there will be no need for a 'real' model.

 

[humber]

I don't get this thread at all. I understand that people argued with humber when he was derailing other treads but over 1000 posts in his own thread arguing complete nonsense like the following quote. What the reason to argue with someone that definitely don't want to learn, having a discussion and don't have a clue about the basic concepts that he is using.



Humber, you show for probably the 1000 time that you don't have a clue about the meaning of reference frame.

No, Fredricks, you think you understand frames of reference, but you do not.
Nope. All that the treadmill provides, is the unusual case of "literally figurative" knowledge. It is all outside of the system that you are testing. You are 'looking' across or at frames, when on the belt, but not within that frame. You are holding the "windspeed frame" in your mind, because you can't do otherwise. The point is Fredericks, is that you can't build a "frame of reference" in this way, if at all. You are trying to build a new "reality" by connecting the model to the idea of figurative frames. You can only build the model.

 

[humber]

If that would be true, then the cart would move backwards, _with_ the belt, _through_ the air. It is clearly visible that instead that cart remains staionary to the air, while the belt is moving.

How. The air in the room will be the atmosphere above your new rubber plane. There can be no motion between that infinite plane and the air. Huge drag problem. With no relative motion of the "belt" no force to drive it anyway.

When i would step on that belt, i would be moving along with it, so yes, the cart does move away from me.

No it's connected by a block of rubber. Directly from wheel to foot. There can be no motion of the belt w.r.t the air. It is part of the frame, stuck to the rubber.

Dude, do you even recognize how stupid it is what you write? It is beyond any reality. Freezing time? Are you kidding me?
[/QUOTE
Whereas standing by the treadmill at "windspeed" is not nonsense?
No, you don't freeze time any more than there is a hobo. The actual transfer is as you experience it. When you keep all of the information within the frame, you see it how it really is. Motionless.

Under that condition none of your shiny toys, that you like to bring up all the time, would work either. No radar gun, no accelerometer, no hand. Nothing. Freezing time means that absolutely everything stands still.

Yes, there certainly are many problems when you try to create a new "equivalent" world view from just a belt. I have said that, you know.

What do you try to achieve by posting such blatant stupidity here? Making yourself the laughing stock of the forum?
You can not make such statements and expect that people will take you serious. What you just posted is by far the dumbest, non-sensical thing you ever posted.

Don't think so. It's not my cart spinning its wheels on a belt.

And what the heck have my feet on the belt to do with the cart on the same belt? Exactly, nothing at all. In case you missed it, the cart has wheels.

Wheels do not imply motion.

You know, these tiny little things that spin around. The ones that drive the prop. You know, W_H_E_E_L_S! These things here! Not these here!
Unless you glue them to the belt, they will do what wheels do: rotate around their axis. Do you grasp at least this simple concept?

From which frame do you see this so-called "spinning ". You are just making that up.

This post of yours is really an insult on everyones intelligence, even on my cats intelligence.

Even your cat...well.

Edit: Btw, no, the cart would not be in the same frame as me. It would only be if i glue it to my body, or if i would sit in it. What you just said that when i jump on the street, in front of any car, no car would ever hit me because it would be in the same frame as me. Frames of reference are not picture frames, in case you didn't know yet.

No, of course not. Are you suggesting that things travel?

 

[humber]

I've noticed that, but surely finding facts to be disagreeable is no reason to constantly disagree with them.

If they are said to be facts.

Take the cart, for example. Spork has posted numerous videos of the cart accelerating against the direction of the belt. When the cart's motion is arrested, and even reversed by spork pushing back on it with, appropriately, as spork, the cart regains it's lost velocity.

Do you think you can reverse a real cart with a fork, and have it bounce back?

Ignoring all this, you focus on the one video where spork tilts the treadmill so the cart remains in place, and argue, against all reason and facts that the cart always remains stationary, and then build up fancy and absurd explainations as to why the cart always remains stationary when it's obvious to anyone who has seen the videos that it does not.

Simple, not absurd. The supporting puzzle, has the cart much as I described. This behavior is also quite in accordance with the described experiences of the tuning process.

Your exaggerated confirmation bias denies reality to such a degree that it boarders on insanity.

As I just pointed out, the videos, which I assume you've watched, clearly show the cart travelling relative to the belt, in the opposite direction to the belt's relative velocity to the ground. In fact, even if the cart was "hovering" in place, as you claim, it would still be moving relative to the belt.

It goes backwards in video #7, quite a lot, with no applied force. There is enough energy to make it crawl like that.

If the cart is moving relative to the belt then your claim that there "there can be no motion between the cart and the belt" if "If there is no motion between the belt and your feet" is clearly gibberish.

No, there need only be a small imbalance. It is quasi-stable perhaps. It has rather a long settling time.You see the motion is around its setpoint.

If you want me to address these points, describe the problem(s) in full. These condensed notes may make sense to you, but they don't make much sense to me.

Why not. Is there not yet enough evidence? You will deny this for the sake of a wind blown cart?
ETA : Who's not here Brian-M?

First of all, moving is not the same thing as accellerating. Feynman's statment was about motion, not acceleration.

Thanks for the tip. No, it was assumed he was talking only of linear motion, his remarks is general and informal. He assume his audience would see that. He was a practical guy.

But seeing as you're the one who brought up the Einstien lift experiment in the first place, surely you should be aware that Einstein concluded that there was no way to tell if the lift really was accelerating through space at 1G, or if it was just sitting motionless on the surface of the earth?

In which case, both Einstein and Feynman disagree with you.

No, he did not conclude that. The surface of the Earth is under constant acceleration. He concluded that you can't shut acceleration out. Absolute acceleration has quite some validity. Check it out.

 

[John Freestone]

That is the question John, You do hold to the view that the observer is the important matter, and not the external environment? That is the point of the box car, I expect?

No. You misunderstand frames of reference, thinking that they are about 'the observer'. They are so only in a very trivial sense. We use thought experiments of putting an observer at a particular velocity, so as to assess the situation from that imaginary person's frame, but their observation has nothing to do with it really. We are observing it as mathematicians. The inertial frame of reference isn't a person's eye-view or a position in the system, but, in the sense we have been using it, a coordinate system for velocity: we choose a particular part of the system that we want to consider as at rest, and we measure all velocities relative to that part.

Now, to understand that, you'd have to grasp that velocities are always relative - there is no absolute velocity (or if there is, it is a cosmological observation of very little use in simple, human-scale mechanical problems!). Some of the questions of the "What can you discover without seeing outside" were posed to you to help you recognise that. And, of course, as actual human observers, we do notice that we cannot discern velocities, only accelerations, a point you are still disputing, but which we believe has been established quite well enough not to be overturned by your faulty mathematics. The relative velocities (the only kind) measured with reference to a particular coordinate or part of the system are the actual velocities an observer would note other things moving at, since they are the origin of the velocity coordinate system, they are nominally 'stationary', so it is a useful to do the "If I was glued to the belt..." or "If I was on the ground..." trick.

Those are questions about that observer's knowledge. How else can I phrase them?

Your question just rambles on about someone in a car with their hand out the window, asking lots of different questions, most of them quite ambiguously phrased. If you are at all genuine, which I very much doubt by the level of arrogance with which you put your arguments in the face of all the world's physicists, you would need only to consider: what is the system I am investigating (clearly put and reasonably maintained without suddenly adding air rams and doppler radar); what is there that I am measuring ALL velocities with reference to (clearly put, and not then accelerated from one speed to another, without taking account of that in all those measured velocities - this is what you do again and again to prove that wind is going in the wrong direction, etc.) and; what is the question (i.e. what velocity or condition, specifically, am I trying to assess). If you expect physical and mathematical answers, you must start disciplining your language into physics and maths, not ramble on about cars in front and 'if you take away that information' and 'pretend that you didn't know', and then top it all off with "So what do you think, John?" What do I think about what, the make of vehicle, or what day of the week it's happening on? Is the driver a roman catholic?

I offer you the alternative to please explain the consequences of zero relative velocity at waterspeed; that which I cheekily refer to as "bullet time" or "ducks in a row". I find that this to be an inevitable consequence. Do you?

I don't know what bullet time or ducks in a row means. I noticed you used those phrases at one point. But look at your request: "please explain the consequences of zero relative velocity at waterspeed" - the consequences?...

I have to assume, even, that you mean zero velocity of a boat (or duck, if you prefer), or a raft or some perfect object travelling with the water at the speed of the water in the direction the water is travelling. The 'consequences' are just as I described several times regarding these boats and balloons. I haven't changed my mind, just increased my understanding a bit as I discuss it with you, thanks to the clever people here. There is no bow wave, no wake, and if there are forces laterally, which there are, they are balanced. There is no acceleration unless an external force is applied, like the wind gets up and pushes the bit of the boat sticking out of the water. Et frickin' cetera. How many times and in how many different ways do you want standard physics explained to you, only to refute it again - 'cause you will. I write these little essayettes knowing that you'll come back with "No, that's not right - water is not a bridge" of some such (hey, that was actually quite a good humb-ism). Ducks in a row, bullet time? See, by now, even if I say "WTF?", it's only rhetorical. I have no hope of you ever writing better physics than might have been obscured by pictures of bison when they decided to redecorate at Altamira.

 

[John Freestone]

Ah, there you go, humber. Spacediver seems to agree with me:

the reason i didn't answer this was because I have no clue what the question is. Please rephrase the question in a manner appropriate for a physics exam.

 

[RossFW]

I think you are a follower of Heliocentricism.

Does that mean you AREN'T????

 

[humber]

I don't know what bullet time or ducks in a row means. I noticed you used those phrases at one point. But look at your request: "please explain the consequences of zero relative velocity at waterspeed" - the consequences?.

If there is no motion between the boat and water, then that applies to that immediately attached to the hull. That in turn has no motion relative to the next bit, and so forth. The water must be one immobile mass ( at least w.r.t the boat, whatever that means). You have made the hobo's interior, real.

I have to assume, even, that you mean zero velocity of a boat (or duck, if you prefer), or a raft or some perfect object travelling with the water at the speed of the water in the direction the water is travelling. The 'consequences' are just as I described several times regarding these boats and balloons. I haven't changed my mind, just increased my understanding a bit as I discuss it with you, thanks to the clever people here. There is no bow wave, no wake, and if there are forces laterally, which there are, they are balanced.

It's staggering in its scope. A-B =0.
How clever is it to tell you that all is frozen at windspeed? That all objects travel at windspeed because a balloon does? John, they are lighter than air objects. If you build a cart with the required characteristics, you will actually have a balloon.

 

[John Freestone]

...and when spacediver poses a well-formed question, your answer is just as irrelevant to physics as your questions

I any remotely realistic situation, the ballons position would be limited, but indeterminate.

Christian makes an appearance, and you forget that to pose him this brilliant observation:

So Christian<snip>

It wasn't worth quoting the whole thing; I'll paraphrase: "...Freeze time. Now look, there's no wind, and the cart is continuously the same distance away from you. You said it would move, so you're wrong."

You're starting to make a habit of proving your wrong velocities by freezing time. I wonder if that's because velocities don't exist when you do that. Velocity = distance (in a particular direction) divided by time.

Freeze the motion of your hands over the keyboard. Now, see how much less nonsense you're typing? 100%, isn't it?