Merged DDWFTTW in a “Real” Wind

[jadebox]

For balloons to travel at WS, a great deal of other theories, not connected with aerodynamics, would also be wrong.

For the balloon to not travel at windspeed, it would need a source of energy to allow it to push back against the wind and some link to the outside world in order to know which way to push. Please point us to the theories that explain how it accomplishes these two things.

-- Roger

 

[3point14]

Where "everyone" is TAD and the Carteers. "Everyone else", including text books and Drs Kammen, Camp, Rhett et, all are not in agreement with TAD.

Windgrins posted this from a reference:
"As can be expected, the solution is invariant under adding a constant to all velocities, which is like using a frame of reference with constant translational velocity."

Meaning the energy is conserved. The constant, the translational velocity, Vt,
means that KE = 1/2m (V +Vt)^2 and not the sum
KE = 1/2m (V)^2 + 1/2m (Vt)^2


From all responses, 3.14, it seems that study has not been in depth, but one of personal enlightenment via "intuition", based upon self-generated and answered thought experiments.

Einstein did not base his resultant theory on his thought experiments, but used them as a means of description. His experiment where he uses two flashlights and a book to show that E=mc^2 is brilliant, but not proof. But then, he knew that.



Then the math should work, shouldn't it? For balloons to travel at WS, a great deal of other theories, not connected with aerodynamics, would also be wrong.

I'm afraid that everyone else in the world believes that, when two objects are converging in a vacuum it is only the relative speed that counts. Their speeds relative to some other point are completely irrelevant.

Everyone else agrees that a balloon in the wind travels at windspeed.

Everyone else agrees that the road moving under the cart is exactly the same as the cart moving over the road.

About these three things (okay, the first and last are practically the same) you are wrong and everyone else in the whole world who's ever thought it through* disagrees with you.


(*Barring those incapable of understanding it at all, of course)

 

[windgrins]

Humber's Perceived Errors in statements

That means energy is conserved, and is the contrary of what you hope to say. One rocket at 2V has 4 times the KE of one at V. So the collision will not be the same.
The problem Carteers have has nothing to do with frames, but a simple schoolboy error that has been made into a theory. TAD have been told countless times they have made this error, and now Prof Rhett has told them again, and with an in-your-face example from Mythbusters.

KE is quadratic with velocity, so KE =1/2mv^2 simple and linear addition is not possible.


The TM is a monumental error. Velocities may be added linearly, and that is what is meant by them being relative: there is no dependence upon some absolute frame or magnitude of the velocity ( for speeds of interest to us).

Velocity is not speed. When making the transform, one may add or subract speed or velocity, but the latter may not be treated as speed.

If the arithmetic result changes sign an that is simply accepted, error may result. It is expected that the reader of the text knows how to handle such math, and when the use of RMS may be a way to do that for example.

The TM is a monumental error. Taking the constant speed from from the wind, brings it to zero, but taking it from the ground, makes it negative. That is a reversal of the relationship of wind and ground that does not exist.
Dr Camp says that the making the road a belt that is moving backwards, is an invalid transform and that is the reason why.

Humber,

I believe I did understand the statement-"As can be expected, the solution is invariant under adding a constant to all velocities, which is like using a frame of reference with constant translational velocity."

What the reference means concisely is:

For a closed system, Pick an IRF, specify all the vector velocities of all the entities in question before the event in question and compute the Energies using those velocities. After the event occurs, COE states the the numerical sum of the Energies of all varieties will be the same as the numerical sum of all Energies before the event in question.

Specifically since there is only "the event", all observers will observe the same event and their physics rules will be the same from any IRF. When one IRF is translating linearly wrt to any other, the arithmetic details will differ but the answers will be the same. Specifically, it is an indication to beginning physics students that if the results from their calculations are different when viewed from two different IRFs, that they have made an error in understanding or their calculations.

One should not assume that some of the posters here do not understand that for KE calculations the translation should be in the "v" part of 1/2mv*2 before the calculation is executed and that this is a vector velocity for more than simple treatments. To state this concisely, pick reference frame, compute all KEs and PEs wrt to that frame. To translate to any other frame, translate all vector velocities and recompute all KEs and PEs wrt the the 2nd frame if required. Most posters understand that the velocity and momentum are vectors and that KE (and energy in general) is a scalar computed from the vector components wrt to an arbitrary but defined IRF.

One salient note:

One should not assume that one knows the educational level of the poster one is addressing unless stated by the poster and their competence with physics and mathematics. Their quality of posts should speak for them in that regard. One should not assume that, because the posters reduce the complexity of an issue to a low level (while retaining the cogent features), that the posters are necessarily incapable of working the issue at a much more sophisticated treatment level.

I believe from the quantity of posts and the information contained, I am satisfied that I understand the disconnect with your level of understanding and my own. I think I will sit this out for a while also.

When you have the "Top Secret" cart ready, let's see it. It must be subtle indeed as you mention it quite a while back.

Regards,

WindGrins

 

[humber]

... assuming the "stationary car" is just stopped and not bolted to the ground or whatever.

That makes no difference at all. If the car is bolted to the ground, then it gains the entire mass of the planet, which is not at all the same thing as two cars of the same mass.
Apart from that, adding that mass is not possible, so resolves to the strength of the mechanical attachment to the ground, much as it does for a wall. That does nothing than change the displacement of the wall or car as a result of impact. 2KE is 2KE, and that it that.

.
Another way of saying almost the same thing you just said is to consider the head-on collision from a reference point moving along with one of the cars.
To an observer on the ground between the cars, each is moving 60 mph towards each other and 0 mph after they hit.

That is a simple error of translation. The cars are said to be moving at 60 mph wrt a common reference, or you couldn't assert the velocities in the first place. How else can it be done?
In this this case, that reference is the ground. If that 0mph reference is moved to "in between" then that transform must be applied to both the objects, and their velocities accordingly adjusted. .

So each goes from 60 to 0 mph. But, an observer moving with one of the cars sees one car going 0 mph and the other coming towards it at 120 mph
before the collision.

Then the observer is not at the original reference that allowed the two 60mph velocities to be asserted, but is now at one of 120mph. That produces one car at 0mph, and one at a speed of 120mph, and not two at velocities of 60mph. The error is that the "transform" has changed the physical reality, because the signs that indicate velocity have been ignored.
-60mph and +60mph become 0 and -120mph or +120mph, dependent on which car the "observer" chooses.

After the collision, both cars are moving away at 60 mph. So the speed of each car changes by 60 mph (0 to 60 and 120 to 60). Therefore, the damage caused to each car is the same.

The "observer" must be now be moving at 60mph to see that, not 0mph.
Again, you must re-transform

I think Humber has a problem understanding the relativity thing or is being obtuse about it on purpose. It's a common theme of this thread.

It is the Carteer's view that is wrong, because they have produced a world where the observer changes reality, as a result of simple arithmetic errors, and misunderstanding of the true role of an "observer".
It was not accepted even before Einstein, that the physical world would be dependent upon the observer, but there were some anomalies. Einstein's switch to space-time, rather than space and time, resulted in a set of physical laws, totally independent of the observer.

 

[mender]

Where "everyone" is TAD and the Carteers. "Everyone else", including text books and Drs Kammen, Camp, Rhett et, all are not in agreement with TAD.

No; you're the only one in your camp, as you well know. You have yet to prove any of your assertions. There's a simple reason for that; they're wrong.

The one thing you do well at, and everyone I think will agree including Drs Kammen, Camp, Rhett, et al, is to draw attention to otherwise ignored details; ignored because they are so well known and understood that they form the foundation and structure of physics.

In the same way that "unsolicited paintings" draw attention to otherwise ignored buildings that line the streets, you get us to look again at the mundane. The integrity of the building is unaffected by the images placed on it but you would have us believe that the tunnel that you paint on the brick wall actually contains a train bearing down on us.

We're not fooled but some of us are a muse.

 

[3point14]

I'd just like to add that this is my favourite thread ever!

 

[mender]

Then the observer is not at the original reference that allowed the two 60mph velocities to be asserted, but is now at one of 120mph. That produces one car at 0mph, and one at a speed of 120mph, and not two at velocities of 60mph. The error is that the "transform" has changed the physical reality, because the signs that indicate velocity have been ignored.
-60mph and +60mph become 0 and -120mph or +120mph, dependent on which car the "observer" chooses.

Perfect example, thank you.

The word picture you are trying to paint has no substance. Asserting that one vehicle no longer has a velocity to "prove" that the transform is incorrect is the same as painting a tunnel on a wall. It might be a convincing image if seen from a very specific viewpoint but fails immediately upon closer examination. And at no time was it ever a tunnel, despite you making loud proclamations and train noises.

But you do keep things lively by forcing us to clean up after you.

 

[humber]

No; you're the only one in your camp, as you well know. You have yet to prove any of your assertions. There's a simple reason for that; they're wrong.
The one thing you do well at, and everyone I think will agree including Drs Kammen, Camp, Rhett, et al, is to draw attention to otherwise ignored details; ignored because they are so well known and understood that they form the foundation and structure of physics.

Uh...huh. There are those who spend their entire careers studying how fluids flow. It is a complex matter that has taken Centuries to bring to its current state of understanding. The simple assertion that if x travel at the same speed as y, does not allow all that work to be ignored or denied, so that some may turn the world into an infant's play pen, while making the most basic of errors at the same time.

In the same way that "unsolicited paintings" draw attention to otherwise ignored buildings that line the streets you get us to look again at the mundane. The integrity of the building is unaffected by the images placed on it

How about an "image" that reads
" Derelict. Condemned to Demolition
Court order...."

but you would have us believe that the tunnel that you paint on the brick wall actually contains a train bearing down on us.
We're not fooled but some of us are a muse.

And Gullible may have the capacity to learn, and realise that TAD have no qualifications or knowledge worthy of interest.

 

[jadebox]

Then the observer is not at the original reference that allowed the two 60mph velocities to be asserted, but is now at one of 120mph. That produces one car at 0mph, and one at a speed of 120mph, and not two at velocities of 60mph. The error is that the "transform" has changed the physical reality, because the signs that indicate velocity have been ignored.
-60mph and +60mph become 0 and -120mph or +120mph, dependent on which car the "observer" chooses.

As I said, humber fails to understand frames of reference - though I still suspect he's doing it intentionally.

-- Roger

 

[CORed]

Where "everyone" is TAD and the Carteers. "Everyone else", including text books and Drs Kammen, Camp, Rhett et, all are not in agreement with TAD.

Windgrins posted this from a reference:
"As can be expected, the solution is invariant under adding a constant to all velocities, which is like using a frame of reference with constant translational velocity."

Meaning the energy is conserved. The constant, the translational velocity, Vt,
means that KE = 1/2m (V +Vt)^2 and not the sum
KE = 1/2m (V)^2 + 1/2m (Vt)^2


From all responses, 3.14, it seems that study has not been in depth, but one of personal enlightenment via "intuition", based upon self-generated and answered thought experiments.

Einstein did not base his resultant theory on his thought experiments, but used them as a means of description. His experiment where he uses two flashlights and a book to show that E=mc^2 is brilliant, but not proof. But then, he knew that.



Then the math should work, shouldn't it? For balloons to travel at WS, a great deal of other theories, not connected with aerodynamics, would also be wrong.

No. The only thing that would be wrong is your bizarre misunderstanding of those theories. A balloon at windspeed, is a balloon motionless with respect to the air. If the first is impossible, so is the second. It really is that simple.

 

[CORed]

As I said, humber fails to understand frames of reference - though I still suspect he's doing it intentionally.

-- Roger

The question about humber always has been whether he really believes the nonsense he posts, or whether he knows it's nonsense and is just getting some kind of kick from the hoops he makes everybody jump through to refute it. If he truly believes it, he has shown a remarkable ability to get really basic stuff wrong. If he's trolling, he shows remarkable persistence.

 

[humber]

As I said, humber fails to understand frames of reference - though I still suspect he's doing it intentionally.

-- Roger

No. You and all the Carters are making the rudimentary error of confusing the observer and reality.
Mentally "stopping" something, and declaring that as fact, is a more egregious error than any Flat Earther ever made.
Two cars moving in opposite directions, so the same speeds, but different velocities of 60mph, remain that way, no matter how they are observed. Failing to apply the correct transform, which may result in one at 120mph and the other at 0mph produces an error, that shows up as the doubling of the KE, and so instantaneously free energy. ( 20000J in the case of the missiles).
The claimed cart is a PM machine, and the TM promotes that, even if you are not aware of that fact.

 

[mender]

The simple assertion that if x travel at the same speed as y, does not allow all that work to be ignored or denied, so that some may turn the world into an infant's play pen, while making the most basic of errors at the same time.

Exactly. That's why you can't expect anyone to take you seriously.

 

[mender]

He's trolling, and he shows remarkable persistence.

Fify. This has been known for quite some time; the only question is why does he persist? Just to entertain RP? And even he said that persistence was futile, so ... ?

He did say he was lonely. He gets frantic when no one replies too.

 

[mender]

The claimed cart ...

The cart is "claimed"? Are you now questioning its existence?

 

[humber]

Exactly. That's why you can't expect anyone to take you seriously.

The "condemned" image works both ways. It may be enforced if legitimate, or allow an ambitious developer to get away with it without attracting undue attention.

 

[humber]

Fify. This has been known for quite some time; the only question is why does he persist? Just to entertain RP? And even he said that persistence was futile, so ... ?

He did say he was lonely. He gets frantic when no one replies too.

Whimsy set to "panic"

The cart is "claimed"? Are you now questioning its existence?

All and more. Its existence is due to the exhumation of historical errors, and the claimed explanation for the apparent record, and the cart's principle of operation, are due to ignorance.

 

[mender]

The "condemned" image works both ways. It may be enforced if legitimate, or allow an ambitious developer to get away with it without attracting undue attention.

But you fail as an inspector.
As I said, your "artwork" in no way affects the integrity of the structure.
Don't let that stop you making woo-woo noises though, you excel at that.

 

[mender]

All and more. Its existence is due to the exhumation of historical errors, and the claimed explanation for the apparent record, and the cart's principle of operation, are due to ignorance.

Chugga chugga.

 

[jadebox]

No. You and all the Carters are making the rudimentary error of confusing the observer and reality.

No ... you're the one who seems to believe that changing the frame of reference changes the physical reality of the situation.

Mentally "stopping" something, and declaring that as fact, is a more egregious error than any Flat Earther ever made.
Two cars moving in opposite directions, so the same speeds, but different velocities of 60mph, remain that way, no matter how they are observed. Failing to apply the correct transform, which may result in one at 120mph and the other at 0mph produces an error, that shows up as the doubling of the KE, and so instantaneously free energy. ( 20000J in the case of the missiles).
The claimed cart is a PM machine, and the TM promotes that, even if you are not aware of that fact.

I didn't mention velocity (other than specifying the directions the cars moved in relation to each other) and I didn't mention kinetic energy.

But, I will now.

"Two cars moving in opposite directions, so the same speeds, but different velocities of 60mph, remain that way, no matter how they are observed." is total gibberish - "60 mph" is a measure of speed, not velocity, and speed is always relative to a frame of reference.

"... shows up as the doubling of the KE" - The "doubling of the KE" is real when you change the observation point, but it doesn't change the outcome of the collision.

No matter how you observer the situation, the kinetic energy converted to "crunch" is the same when the two cars hit. The difference in observation, however, affects how much kinetic energy you see in the result. In the case of an observer seeing the two cars crashing to a stop, there is no kinetic energy remaining, because the vehicles have stopped. In the case of the observer moving the same speed and direction as one of the case before the crash, there is remaining kinetic energy because, after the crash, the two vehicles are moving away from the observer.

If the two cars have a mass of 10kg each and are moving towards each other at 10 meters/second, the kinetic energy of each car is 1/2 * mass * speed^2 or 1/2 * 10 * 10^2 or 500J. The total kinetic energy of the two cars is 1000J.

Now, change the reference point so that one car is moving 0 meters/second and the other is moving 20 meters/second. The kinetic energy of the second car is now 1/2 * 10 * 20^2 or 2000J - 2000J is twice 1000J. But, after the collision, the two cars will be moving, relative to the observer, at 10 meters/second. The kinetic energy of the two cars is 1/2 * 20 * 10^2 or 1000J.

Subtracting 1000J from 2000J, you get 1000J. The change in kinetic energy is the same for both observers. The different observers see different things, but the physical reality of the situation doesn't change.

-- Roger