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

[Christian Klippel]

Double post

 

[Subduction Zone]

Reading humber's post #856 I had to triple check that it wasn't humb. We have this little gem:

No. What allows relative motion between two connected objects? Friction.
The velocity develops across the friction of the interface. Without contact with the belt, there is no "wind" for an object on the belt

And then of course there is this:

The wind, is dependent upon that friction.

And here all of this time I was believing those dang weather men with their warm fronts and cold fronts. Well I know better now. Thank you humber.

 

[jjcote]

I read this stuff, and I'm tempted to post corrections to humber's wild assertions, but there are so many that it's a wild goose chase. I'll point out just a couple:

I believe humber asserts that somebody on the treadmill with roller skates and a parachute can remain stationary with respect to the air, but somebody on a floor with skates and a parachute in wind can't travel at windspeed. That's flatly wrong. If one works, the other works.

humber has asserted that a balloon will not travel at windspeed, because the propelling force of the wind can't ever completely overcome the air resistance. That's flatly wrong. There is no air resistance impeding forward travel unless the balloon is going faster than windspeed. (Same deal for the mythical bow wake of a canoe moving at the speed of the current.)

humber has asserted that he has seen oranges remaining stationary on flat, level, moving conveyor belts with no external forces in play. That's flatly wrong. An orange is going to have some rolling resistance, and there has to be some force to counteract it. Unlike the treadmill cart, for which we have excellent video evidence, kits available for people who want to replicate the experiment, and an offer from the makers to make more videos with any questionable issues addressed, all we have is humber's recollection about the oranges. Show us the video. Show us the oranges, and we'll explain what's really going on, be it a dip in the belt or something else. The one thing I'll promise is that it isn't the "force balance" explanation that you have put force, because that makes no sense.

Do you ever wonder about the fact that this forum is rife with educated people who are in agreement about these matters of physics, and you are the only purportedly real person with this twisted outlook?

Now, a question for the rest of you:
Without searching back through all of the posts, would anybody out there like to take credit for coining the terms "humberian physics" and "humberverse"?

And what ever became of tsig?

 

[John Freestone]

By not being specific about "the differential velocity between the wheel and belt" it can either be positive or zero.

You forgot negative. It's "positive" in the wind, and "zero" on the belt.

No, it is positive or zero, unless I do not understand what you mean when you say "the differential velocity between the wheel and belt". I thought you described that velocity rather well, and I imagine that it means the speed past each other of the two things: wheel and belt. If that is what you meant, then when is it negative? I presume that you are considering the condition where the wheel is moving forward over the belt or (as you insist is fundamentally different) the belt is moving under the wheel.

Which ever we use, the differential velocity of those two does not alter a jot. You may have as yet unclear objections to equivalence of frames, but even you must surely admit that if I slam a wall into a car at 90 miles an hour, or a car into a wall at 90 miles an hour, or any other velocities that add up to 90, the closing velocity will not change. So it is with the wheel moving on the belt.

The bit you didn't specify was what you mean by 'wheel'. 'Belt' (at the top surface) is at a constant velocity, but the wheel is rotating. The axle's relative or differential velocity compared to the belt is v (the velocity of the cart relative to the belt, obviously); the velocity of the point of contact is theoretically (in a perfect mechanical system) zero w.r.t. the belt, and the top of the wheel is going at 2v w.r.t. the belt. Nowhere, as far as I know, is a wheel moving at a negative velocity wrt the surface it is moving over, unless you arbitrarily change the sign or it starts moving backwards.

Saying it is positive "in the wind" and zero "on the belt" is a stupid way to look at it, and, besides, you just said it was also negative, but didn't say where. Where is it negative, under the water in the fishtank?

There's a point on the wheels at the bottom that is at zero wrt the belt, ...

(a) Is that the contact point that lies just behind the axle, or the smaller one just ahead of it?
(b) Still not the same on belt or in wind, are they? (c) Until I get a better rebuttal, I think that I am going to stick with that.

(a) What the hell are you talking about now, in front and behind the axle? What part of "point on the wheel at the bottom" did you not understand? Are you going to explain that when a wheel makes contact with a surface it has more contact behind the axle position than in front of it? Are we off chasing more irrelevant complications, even assuming there were some truth to the assertion?
(b) No they are not the same on the belt or in wind, if you want me to agree for the sake of it. Since the sentence doesn't mean anything anyway, I can go either way. The "differential velocit[ies] between the wheel and belt" (your term) are all equal to the differential velocity between the wheel and road, when the same cart is travelling at the same velocity w.r.t. the surface it's running on, if that's what you mean.
(c) Please yourself; it is not a rebuttal, it is simply orthodox mechanics that we should expect our children to leave school understanding. Stick with what?: you didn't have anything to stick with. I am only still replying to you because you're like a recurring itch. You haven't had anything that could remotely be described as a position (other than wriggling and jumping up and down) since you started.

 

[John Freestone]

humber has asserted that he has seen oranges remaining stationary on flat, level, moving conveyor belts with no external forces in play.

Motion without a force? I thought that didn't happen in the humberverse. Must just be balloons.

 

[Christian Klippel]

Now, a question for the rest of you:
Without searching back through all of the posts, would anybody out there like to take credit for coining the terms "humberian physics" and "humberverse"?

Hello jjcote,

here are the results for three things, "humberverse", "humberphysics" and "humberian physics" in chronological order, that is, when they were first mentioned. They are all in the original Down wind faster than the wind thread.

For "humberverse" we have the first post here:

*I propose we call this place "The Humberverse", in honour of the first of its citizens to make contact.

Then we have "humberphysics" here:

would be quite some fun to compile a "best of humberphysics"

And finally for "humberian physics", it is here:

The extreme stupidity of Humberian Physics not only confuses us about the subject, but about what each other is saying about it!

Does that answer your question?

Greetings,

Chris

 

[humber]

Reading humber's post #856 I had to triple check that it wasn't humb. We have this little gem: And then of course there is this: And here all of this time I was believing those dang weather men with their warm fronts and cold fronts. Well I know better now. Thank you humber.

Well, thank you for your agreement that the velocity gradient develops across the wheel to belt friction, and that treadmill wind cannot be at all like the real thing.
To clear up the other point, the wind in question was of course the treadmill wind. I neglected to add the double commas, as in the corrected quote below:

"The velocity develops across the friction of the interface. Without contact with the belt, there is no "wind" for an object on the belt. The "wind", is dependent upon that friction. When the cart is held, the force is such that that "beltspeed" develops across the interface.

 

[CORed]

Once again, humber fails.

Humber, if you don't want to be taken as an idiot, don't act like one. The problem was clearly stated "using the resources available to the cart". The cart has neither sail nor skates.

Even if you were using this as a metaphor for moving yourself as an observer into a position to see the interface between the wheel on the cart and the belt (which incidentally does have zero differential velocity), you and your chute would be much smaller than the cart and therefore more affected by the wind shear of the belt wind interface. You would not be able to keep up with the cart even if the cart were hovering stationary relative to its air.

It's off the end of the treadmill for you. The chute should let you safely descend the treacherous 15 cm drop but how are you going to escape the cat.

It's just a force balancing cat and not a valid model for a cat walking in the real world.

 

[spork]

Well, thank you for your agreement that the velocity gradient develops across the wheel to belt friction, and that treadmill wind cannot be at all like the real thing.

I figured humber read all our comments as being in perfect agreement with him. That's certainly been his M.O. with any other evidence we've provided.

 

[Christian Klippel]

It's just a force balancing cat and not a valid model for a cat walking in the real world.

Hello CORed,

you forgot to mention that the forces balance for the cat only because her paws are sliding! How could you! Not to mention that her tail stores lots of KE to keep the cat on track....

Greetings,

Chris

 

[jjcote]

Well, thank you for your agreement that the velocity gradient develops across the wheel to belt friction, and that treadmill wind cannot be at all like the real thing.

I figured humber read all our comments as being in perfect agreement with him. That's certainly been his M.O. with any other evidence we've provided.

It's hard to know how anything could be in agreement with that quote from humber. It's yet another sentence that I can parse, but that contains no additional meaning. "the velocity gradient develops across the wheel to belt friction"? WTF?

 

[humber]

I read this stuff, and I'm tempted to post corrections to humber's wild assertions, but there are so many that it's a wild goose chase. I'll point out just a couple:

The best way to resist temptation is to give into it.

I believe humber asserts that somebody on the treadmill with roller skates and a parachute can remain stationary with respect to the air, but somebody on a floor with skates and a parachute in wind can't travel at windspeed. That's flatly wrong. If one works, the other works.

No, he says that first statement has nothing to do with the second.

humber has asserted that a balloon will not travel at windspeed, because the propelling force of the wind can't ever completely overcome the air resistance. That's flatly wrong. There is no air resistance impeding forward travel unless the balloon is going faster than windspeed. (Same deal for the mythical bow i wake of a canoe moving at the speed of the current.)

How does the water know it should get out of the way? How much warning does it need? I mean real water, not ducks in a row.

humber has asserted that he has seen oranges remaining stationary on flat, level, moving conveyor belts with no external forces in play. That's flatly wrong. An orange is going to have some rolling resistance, and there has to be some force to counteract it.

They really do. Still, I am sure you can think of a way that they might.

Unlike the treadmill cart, for which we have excellent video evidence, kits available for people who want to replicate the experiment, and an offer from the makers to make more videos with any questionable issues addressed, all we have is humber's recollection about the oranges. Show us the video. Show us the oranges, and we'll explain what's really going on, be it a dip in the belt or something else. The one thing I'll promise is that it isn't the "force balance" explanation that you have put force, because that makes no sense.

Is it only the oranges?

Do you ever wonder about the fact that this forum is rife with educated people who are in agreement about these matters of physics, and you are the only purportedly real person with this twisted outlook?

Well done. I do wonder about that.

Now, a question for the rest of you:
Without searching back through all of the posts, would anybody out there like to take credit for coining the terms "humberian physics" and "humberverse"?

And what ever became of tsig?

Or humb

 

[humber]

It's just a force balancing cat and not a valid model for a cat walking in the real world.

I was thinking of putting a carrot on the end of a stick, and hanging it just a head of donkey walking on a belt. Yes, "Donkey at Windspeed"

 

[humber]

It's amazing how a single humber twists anything and everything in an attempt to make him look clever.

No, you do that.

OK Christian.

 

[Christian Klippel]

No, you do that.

OK Christian.

You surely can back that up with some proof, can you? If not, it's just the usual random, meaningless rambling that we are all know from you. Just a lie, a projection. Nothing else.

I mean, is it really that hard? After all, you took that quote right out of a post where some lines earlier it can be clearly seen that you twist things.

Come on, show some proof of that. You know, like the proof for your remaining assertions that you promised us so long ago.

My prediction: You can't. Therefore you wont. Same as with the other proof you promised us.

 

[humb]

Or humb

Oh, I'm still here. I won't abandon you, humber, people like us need to stick together and not be bullied by these other people who totally misinterpret the writings of all of the great scientists who are written in our books. And more! Remember, when Galileo dropped the grapefruit and the clementine from the leaning tower of Pisa, he didn't drop them onto a treadmill! And yet they both sat there spinning in the air, to the amazement of the Pisans. Because it was a simple balance, the air resistance increasing to the point that it was a zer0 sum with gravity. I personally think he should have dropped spork, and good luck if he tried to fly away on one of his contraptions. Does a child holding a balloon suddenly disappear down the street at windspeed? Or get caught in the belt of the so-called "treadmill"? Woo! Woo! Woo-woo!

 

[spork]

I personally think he should have dropped spork, and good luck if he tried to fly away on one of his contraptions.

Here's the contraption we flew last weekend. Unfortunately, the starter bolts sheered, the starter fell off, and one of the bolts took a sizable chunk out of the prop and went clear through the wing. After that it was Hemmingway starts for the rest of the day.

 

[humber]

Oh, I'm still here.

Thanks. You were quite useful.

 

[Brian-M]

You have to be kidding!?

I assure you humber won't and can't answer your questions. Nor does he have any position consistent enough to examine.

Someone has to dream the impossible dream.

 

[fredriks]

Here's the contraption we flew last weekend. Unfortunately, the starter bolts sheered, the starter fell off, and one of the bolts took a sizable chunk out of the prop and went clear through the wing. After that it was Hemmingway starts for the rest of the day.

Whats that contraption? A motorized millenium or swift?