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

[humber]

The tires do rotate without slip at low driven rates. It's only when the mechanical intermeshing of the rubber tread with the road surface is inadequate to prevent slippage that slip actually occurs.
In my line of work that is essentially all the time but certainly not that case of the average car driving down the highway.

Obfuscation. You cannot tell where the load line is by simple observation.
Tyres are complex and plied to react to force.
The cart wheels are not like tyres, but more like disks. There must be compression at the interface for a driven wheel to move forward.
It makes no difference in this case, because the belt cannot enforce any such condition (no matter how you interpret it) upon the wheel.

By the way, the more common term is percentage of slip when discussing longitudinal tire to surface speed differences and slip angle for lateral differences. Note: for higher level discussions, shear angle should be used instead of slip angle to more clearly distinguish between steering angle (direction of the rim), slip angle (direction of the tread), and shear angle (direction of the tread vs the actual direction of travel).

Nothing to to with your earlier claims (now updated, of course), and less to do with the way a belt drives the wheels or contra-rotating shafts.
The counter-rotating drive and propellor shafts, can supply force in the "same direction", so as to reduce the total force within the shafts. This cannot happen on a plain shaft.

The belt drives the wheels and the propeller in counter-rotation; the basis of a feedback control system, that forces the power consumption to a minimum.
This is analogous ( in principle) to the governor found on steam engines. An incremental increase in velocity, causes motion of the rotating mass so as to reduce the power supplied to the engine.

The tires do rotate without slip at low driven rates. It's only when the mechanical intermeshing of the rubber tread with the road surface is inadequate to prevent slippage that slip actually occurs.
In my line of work that is essentially all the time but certainly not that case of the average car driving down the highway.

ETA:
Slip in a tyre occurs whenever force is applied that produces motion. That is not the same as breaking traction.

 

[spork]

I own the IP on that device.

No you don't.

 

[humber]

No you don't.

Do you own any of the 'I' of 'IP'?

 

[mender]

ETA:
Slip in a tyre occurs whenever force is applied that produces motion. That is not the same as breaking traction.

If you had bothered to answer my tire quiz, you might have found out that tension in the sidewalls of the tire transmits the torque to the contact patch on the tread face, and that is what produces motion. The amount of contact patch displacement (in the opposite direction of what you keep insisting on) will depend on the magnitude of the torque and the construction of the tire. None of this has to involve breaking traction or slip.

 

[mender]

You cannot tell where the load line is by simple observation.

Direct observation of a stressed tire through a heavy glass plate and across a pressure sensitive surface shows the centre of force on the displaced contact patch to be located off to the side of the centreline of the tire in the direction of the induced force (centripetal in cornering), showing that the tire is reacting to the force. The tire is elastic and bends, resulting in the attached car trying to continue along its path while the tire tries to pull the car in the desired (by the driver) direction. The contact patch is in "front" of the tire, not behind.

That's why your description is exactly like trying to push a rope; the contact patch of the tire is pulling, not pushing, on the rim of the tire which is attached to the rest of the car.

Tyres are complex and plied to react to force

See above paragraph.

 

[spork]

Do you own any of the 'I' of 'IP'?

I prefer to wait for just a few more posts before answering that. I figure it'll have more impact when there are exactly 100 pages dedicated to your completely ludicrous and inconsistent notions of how the physical universe operates.

 

[humber]

If you had bothered to answer my tire quiz, you might have found out that tension in the sidewalls of the tire transmits the torque to the contact patch on the tread face, and that is what produces motion.

That denies your point, and what I said earlier. The tyre is flexible, so if compressed, producing the distortion ahead of the axle. It would not only be impractical for a tyre to operate by this means, but monstrously innefiicent.
The axle force needs to put the tyre in tension, to produce an effective force from the rear.

The cart wheels are like disks. The action os a pneumatic tyre, plays no part in their operation.

The amount of contact patch displacement (in the opposite direction of what you keep insisting on) will depend on the magnitude of the torque and the construction of the tire. None of this has to involve breaking traction or slip.

Slip is always present in a moving tyre. Look it up 'slip angle'.

 

[humber]

I prefer to wait for just a few more posts before answering that. I figure it'll have more impact when there are exactly 100 pages dedicated to your completely ludicrous and inconsistent notions of how the physical universe operates.

Let me help you along. Your cart is a toy.

 

[humber]

Your treadmill works by magic.

 

[Subduction Zone]

Let me help you along. Your cart is a toy.

His cart may very well be a toy (oh my god humber can actually be right occasionally), but it illustrates a very interesting principle. DDWFTTW is proved possible.

 

[Subduction Zone]

Your treadmill works by magic.

Nope, electricity.

 

[humber]

His cart may very well be a toy (oh my god humber can actually be right occasionally), but it illustrates a very interesting principle. DDWFTTW is proved possible.

Really, SZ? If you went to a hobby shop and took some wheels from the bubble pack display, and then a selection of propellors that were of suitable size ( not too big, but not too small) and then put them together, that the sheer power of the wind might not drive that light object to considerable speed?

However, the treadmill is not representative of the result.

ETA:
I suspect that you do think electricity is magic.

 

[humber]

Direct observation of a stressed tire through a heavy glass plate and across a pressure sensitive surface shows the centre of force on the displaced contact patch to be located off to the side of the centreline of the tire in the direction of the induced force (centripetal in cornering), showing that the tire is reacting to the force.

Correct. The the car moves in reaction to the force. Like this. (from the book)
http://www.internationalskeptics.com/forums/attachment.php?attachmentid=12972&stc=1&d=1234137686
The car is moving to the 'left' so the reaction is to the right.
That is the same when driven. Forward motion, is finds reaction to the rear of the axle, otherwise the axle will not move, or go in the other direction.
I repeat. Now matter how you want to describe it, the belt cannot impose this force upon the wheel. The carts wheels are disks and compression must take place for drive to occur. Like the steel wheel and tracks on a train.

The tire is elastic and bends, resulting in the attached car trying to continue along its path while the tire tries to pull the car in the desired (by the driver) direction. The contact patch is in "front" of the tire, not behind.

You are suggesting that a car can pull itself up by its own bootstraps.

That's why your description is exactly like trying to push a rope; the contact patch of the tire is pulling, not pushing, on the rim of the tire which is attached to the rest of the car.

It cannot do that, so the force is from the rear.
You are also conflating two sources of energy with the cornering argument. The car can move on its own KE, it does not need the tyre to power that motion, but to resist it.

 

[mender]

I do not accept Dan_O's opinion concerning scientific impropriety.
I made one edit, which I made clear was mine. There was no suggestion of my authorship of the remainder.

That wasn't the issue.

I still want you to justify this. "Then you shouldn't be quoting Arkaein's work without proper attribution."

I did not quote him. You have no authority whatsoever.

Contradicted yourself here, humber. So, did you quote him or not? If so, where is your acknowledgment of that?

 

[mender]

Correct. The the car moves in reaction to the force. Like this. (from the book)
http://www.internationalskeptics.com/forums/attachment.php?attachmentid=12972&stc=1&d=1234137686
The car is moving to the 'left' so the reaction is to the right.

Wow. I didn't include that easily accessed picture because it doesn't show the centre of force in the contact patch, only that the contact patch is shifted under the tire as it is deflected by the cornering force. I'm shocked that you would misinterpret the picture so badly. Well, maybe not so shocked.

The contact patch is to the "left" of the centreline of the rim, because the car is turning to the "left" (right rear tire). If you consider the change in direction of the car as acceleration and compare that to a forward acceleration of a car, you'll see that the contact patch is in the direction of the acceleration - in "front" of the tire. The contact patch is again "pulling" on the rim. Just like all the pictures have shown so far. See the tension in the sidewall trying to unseat the bead? If the tire comes off the rim, the tire ends up piled up on the inside of the rim, not the outside.

Does anyone else claim that the contact patch is "pushing" or piling up behind the tire?

 

[humber]

That wasn't the issue.





Contradicted yourself here, humber. So, did you quote him or not? If so, where is your acknowledgment of that?

A few strawmen for the pyre.

I did not post that as an authority, but as a description. I do not take random samples as authoritative. If I do, you get the source.
From the same author:
Note: there are a number of slightly different definitions for slip ratio in use.

Yes, his description was what I was aiming for. The complete process in unlikely to be found in an article not dedicated to generating real forces,
but appealing simulation.

 

[mender]

Maybe you should go by authoritative textbooks on the subject instead of discussion on how to set up a car game simulation then. I can point you to some very good books on the subject.

 

[humber]

Wow. I didn't include that easily accessed picture because it doesn't show the centre of force in the contact patch, only the contact patch is shifted under the tire as it is deflected by the cornering force. I'm shocked that you would misinterpret the picture so badly. Well, maybe not so shocked.

I doubt that you have any other conclusion other than what is explicit in that photo.

The contact patch is to the "left" of the centreline of the rim, because the car is turning to the "left" (right rear tire). If you consider the change in direction of the car as acceleration and compare that to a forward acceleration of a car, you'll see that the contact patch is in the direction of the acceleration - in "front" of the tire.

No. The photo (which I see you do understand) shows cornering force.
That is due to applying a force to keep the car from going straight ahead. Like the force in a string of an object rotated above the head.
You cannot readily see the force provided by the axle.

The contact patch is again "pulling" on the rim. Just like all the pictures have shown so far. See the tension in the sidewall trying to unseat the bead? If the tire comes off the rim, the tire ends up piled up on the inside of the rim, not the outside.

That is because they are opposing forces. The tyre does not pull, but provides a force that opposes the linear motion of the car. (centripetal force)
The contact patch of a driven wheel, provides an opposite reaction to the forces driving the linear motion of the car. It must come from behind the axle. The axle cannot lead itself.

Does anyone else claim that the contact patch is "pushing" or piling up behind the tire?

Who believes in fairy tales?

ETA:
As for the other post. I have already done my homework, thanks.

 

[spork]

That denies your point...

I deny humber

Your cart is a toy.

Correct - it's a simple toy that you can't understand. And you won't even accept that it operates exactly as is plain to see.

Your treadmill works by magic.

Yes, in the humberverse I suspect electricity is "magic"

 

[humber]

I deny humber

Correct - it's a simple toy that you can't understand. And you won't even accept that it operates exactly as is plain to see.

Yes, in the humberverse I suspect electricity is "magic"

Full marks there. Bursting with originality.