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

[mender]

I guess I have to brush up on (or possibly even do) some electrical problems. I've only dealt with such things because of specific jobs and didn't do well on the NSW test.

92.5% on the first test, 53.5% on the second.

 

[jjcote]

Yeah!
100% on the intuitor.com quiz!
Woot! Woot!
I guess that MIT education paid off!
(I also think I'll quit while I'm ahead.)

 

[spork]

Yeah!
100% on the intuitor.com quiz!
Woot! Woot!
I guess that MIT education paid off!
(I also think I'll quit while I'm ahead.)

Hey, keep in mind humber didn't get a single one wrong either!

 

[mender]

Hey, I think getting only three wrong (8, 30, and 34) thirty years after high school physics isn't bad - but yes, 100% is pretty good!

They must have changed some definitions in the last three decades without consulting with me first!

Now to bring you down to earth (or not!) jj, try the other one! I'm pretty sure humber would outscore me on that one if he decided to try it.

 

[Brian-M]

I've just done the first one and got 85%. There are almost two tests going on at the same time. Firstly your ability to understand how "deep to go" when interpreting the question (so that you answer it at the "right level" if you see what I mean) and then your actual knowledge. Out of my six errors I think I'd class about 3 of them as being in the first category. But even when I look at the other 3 there's nothing there I didn't actually "know". So I should really have got 100%!

I think that about half my mistakes on the first test were stupid blunders which I would have gotten right if I'd been thinking straight. On the other hand, it probably balances out the questions where I had no idea and got a lucky guess instead.

 

[Brian-M]

Whoever decides to compile the Principia Humbermatica is going to have a hard time making all the laws fit together.

I'm sure the Principia Humbermatica will find a place alongside that of Newton's alchemical works.

 

[Brian-M]

Expanding on that slightly, I understand that Humber has said he doesn't have any problems with the general concept of a vehicle travelling directly downwind faster than the wind, although he may think that a steady state situation is problematic, and I'm pretty sure he has also said that the spork/JB cart is not one of the vehicles that could actually achieve DDFTTW. I don't recall hearing his views on your tumbleweed device.

My impression is that he thinks it can only go faster than the wind for short bursts using conserved momentum somehow, but that it's average velocity would remain below windspeed.

Of course, he uses a lot of ambigious phrasing and seems to change his mind about fundamental aspects of physics randomly, so you'll have to ask him to find out what he currently thinks of it.

 

[Brian-M]

There's a really great video that shows the cart as a "gear" between air and ground and then shows that it doesn't matter if you move the "air" or move the "ground", the cart moves the same. Someone posted this, I assume. It's really, really straightforward. and shows different inertial frames.

I've made up a couple of animated carts using a wheel instead of a propeller, but it hasn't helped Humber any.



Click to enlarge and see animation.

 

[humb]

Great, a physics test! I'll show you clowns. You think you understand science, when in fact humber and I keep trying to explain it to you and not a one of you will listen. Okay, here I go!
--------------------
Er, this test is no good. I can't submit my answers because most of them don't have a correct choice available. The normal thing to do in a case like this is to show one's work, but there's no way to do that with an online form. Which one of you idiots thought this was a suitable quiz? Here is why these questions are bogus.

1. This is not science, it's a linguistics question, and a trick question at that. I happen to speak Caspian, and in that language, the words pronounced "temperature" and "heat" both mean "quince farmer" (the former a male farmer, the second a widowed female farmer). But they are written in a different alphabet.
2. This depends on your perspective. From a rest perspective, of course not. But if viewed from a distance, then distance x force = work, which is in Newtons, the same as energy. It all depends on how far away you stand.
3. Sometimes yes, or sometimes no. Is she a blonde or a brunette?
4. Hah! I knew you'd try to slip a wind tunnel question in here somehow. I keep telling you, a treadmill is not a kite!
5. This totally depends on the union rules in the shop.
6. There is no combustion energy in gasoline. That's the wrong preposition. "Among" gasoline, perhaps, or "between" gasoline. Therefore the engine will always be more than 100% efficient.
7. I know the answer to this, but I cannot divulge it unless you have a security clearance.
8. Who is this Ben? Franklin? He probably needs electrical energy to move the box, and we don't know what kinds of devices he has for converting what he has to what he needs. Meanwhile, the box has zero KE to start. I suppose with a treadmill, you can claim that it can move 5 meters without going anywhere. Makes things conveniently simple, if only it were true.
9. Mmm hmm. Another trick question. Be more specific. One is dropped onto the rim of a crater, the other is at the same height, but over the center of the crater, I suppose. If a tree falls on the moon, and there is nobody around to hear it, does the lumberjack make a sound when he screams because it hits him on the head?
10. I watched the moon landing on TV, in 1969. Walter Cronkite was announcing, and he had gravitas, and that's more important. I also almost saw Cronkite when his yacht was parked next to my cousin's sailboat when he was married on the deck (but not by the captain, since he was the captain). And let me tell you, no matter what those two boats did, they always had bow waves.
11. Object? Yes, I do! I object!
12. Why is she jumping off a chair in the first place. Probably using LSD and thinks she can fly. Which is higher? I'd say Susan herself is the prime candidate for that honor!
13. No, she appears to be weightless because she's a damn anorexic! They're everywhere, even in space now. Somebody get that girl some twinkies or something!
14. The floor exerts no upward force on her feet, it exerts an upward force on her shoes. There's no way you can ever get those stiletto heels off of that slut.
15. Slowing down? We already had question #9 about feathers speeding up, and now this. Why would you want to slow down anyway. It's already pretty slow. Mine is motionless, it's trapped in my sleeping bag. How do you get down off an elephant? You don't, you get down off a duck!
16. Juan doesn't go around corners. He just sits in the parking lot in his low-rider Chevy, bouncing up and down. Yeah, he's accelerating, all right. Vertically.
17. Uh, didn't we already cover this? Earth in motion, etc? Is this track around the north or south pole? More information is needed! Or next you'll tell me that she wasn't really on a track at all, it was just ynot's ridiculous turntable! And why is she wasting her time doing this, doesn't she have a map?
18. What does this even mean? How can the floor stand on my tiptoes, and if it did, then it would be greater than what? And there is no force between my feet. Small animals sometimes, but not a force.
19. I have had jobs in both of these environs, and although both were generally pretty relaxed, sometimes there was pressure. How much depended on whether my coworkers were jerks. And believe me, when you're working cheek by jowl with somebody at the bottom of a 10 m deep well that's 1 m in diameter, it's difficult to be forgiving.
20. Put it in the water, put it in a sink, put it in another sink. So what?
21. The insect will never hit the windshield. The laminar flow is going the wrong way and will accelerate the insect out of harm's way. Nice try.
22. She throws a ball in the air? What is she, some kind of enchanted fairy? Balls are thrown in ballrooms. They're all over the TV tonight. Oh, look Barack Obama just showed up at Susan's Inaugural Air Ball! I don't think so...
23. No, friction provides the means of keeping spork's fallacious cart in place on the treadmill. Which is not a kite. We've covered this already.
24. We don't know which way the car is traveling when it hits the tree. It could be in reverse. That changes the force balance, doesn't it now? For all we know, the car might have fallen off a cliff and is landing on the tree from above!
25. Did you ever really think about the word "floor". Floor, floor, floor. Doesn't look like it should be pronounced that way. What a weird word.
26. Oh, here's Ben again. Isn't it great how people in these science quizzes can just travel off to distant planets as easily as if they were going down to the corner store to get some kumquats?
27. Should be the same in all frames, so I'll choose the conditions. I'll pick just a hair above the freezing point, with really low humidity. So the smaller amount of water has a greater ratio of surface area to volume, and the latent heat of vaporization will lower the temperature of that one more than the larger one, causing it to freeze, and assume a crystalline form with a lower density. Huh? Huh? Pretty good, right? Or I could easily show the opposite (the proof is left as an exercise for the reader), so the question is indeterminate. QED.
28. Iron can, okay, I have one. People call them tin cans, but they're really made of iron. Or more accurately, steel, which ironically is a purer form of iron than iron. Now I've filled it with gas. This is really a bad idea, you're supposed to keep gas in a jerry can. What am I supposed to do with this again? Hang on, let me put out my cigarette.
Yikes!
Ow!
Damn!
29. A cloud's mass consists mainly of hang glider pilots who are in clear violation of FAR Part 103, as far as I can tell. Probably spork.
30. Need more information. What is the charge of the nucleus? The sun has only one component, so are we talking about hydrogen? And with so many electrons, the question should be asking about an ion. Fix the question and I'll get back to it.
31. How can there be two different flows in opposite directions. It all depends on the history of the temperature. Heat has a velocity, which cannot accelerate without a thermal force. The question is meaningless.
32. Define "almost". And please resolve the koan about "filled with empty".
33. Again I see through your flimsy subterfuge. No matter how I answer this, you will come back with some folderol about what happens what the car strikes the lightning instead. The lightning seeks ground. It is special, and universal.
34. Don't you mean holes?
35. Never send a woman to repair an automobile. This sort of thing always happens. But the outcome depends on the locality. In some, this is not a capital offence, and where it is, the jurists may be able to choose between electrocution, or lethal injection, gas chamber, guillotine, burning at the stake, piranhas, etc. In Jane's case, I'd recommend burning at the stake, because my neighbor told me that she's a witch.
36. Sigh. And next you'll ask what happens if the light bulb is moved through a stationary pool of electrons, I suppose. It is not the same! We have proved this repeatedly!
37. Yeah. There are a lot of things in a cubic meter, with room to spare. What's your point?
38. I refuse to answer this without consulting my attorney. I know my rights.
39. What? Hello? I can't even think with that damn music playing!
40. This seems so redundant. A kid will sound like a chipmunk when he breathes helium, and you gotta figure that a mole will sound that way normally, but it's hard to tell, because they're pretty laconic. Maybe we can get a gopher, that should be close enough. Okay, so he's singing. Pretty high, I imagine. And then the other one is playing lead, I guess that's supposed to mean lead guitar. We're still going to need maybe a rhythm guitar, definitely bass and drums, and one more mole on keyboards would be great. What was the question again?

 

[RossFW]

DAAAHHHMMMM.............YO....DA....MAN!!!!!!!!

 

[Subduction Zone]

I have to give humb 100% on that quiz. That was the best humb ever! I was afraid my girlfriend was going to yell at me since it is almost 2:30 in the morning and I had to peek at this blog. Keep it up humb.

 

[humber]

This reminds me of Humber, for some reason.

[qimg]http://i43.tinypic.com/2dqok20.jpg[/qimg]

Ladies in waiting...

 

[humber]

humber, with 2000 posts, there's no way I"m catching up. Is your issue with the treadmill tied to whether the propeller cart can go DDFTTW? Or do you believe the cart works, and the issue with the treadmill is a tangential discussion?

Hello, Greg. The treadmill is the basis of the windspeed claim and offered as evidence, but I say the treadmill itself is false, and therefore can say nothing either way about the cart. That is easily dismissed from a physical point of view, but its claims are supported by ideas that are metaphorical. That makes it difficult to knock down.

That cart itself is a 'simple' Newtonian device, and nothing to do with "frames of reference". I think DDFTTW is perhaps possible, but this approach looks to me like it would need to break a few physical laws on the way.

 

[humber]

Oops sorry, H'eth. You're quite right. Shame on me.

To save H'eth any more embarrassment, I am not Dutch.

 

[humber]

Greg, meet Humber. Humber, meet Greg.

You two will get along famously.

JB

Marriage is imminent.

 

[humber]

Dutch? Yep! That'll do it!

Worst aircraft accident in history was caused by a Dutch Captain who wouldn't listen when his First Officer told him he wasn't cleared for take off.

700ish people dead 'cause he was right and everyone else was wrong.....

Seems to say more about Captains than the Dutch.

You see, according to our friend Humber, the cart isn't moving at all. Just look!! It's not going anywhere!!

Works for me.

This is variously artuiculated as "The cart has no meaning" "The cart has no KE in any frame" and my personal favourite- "A car may appear to be moving backward WRT you, but it isn't. You can tell by the way it's wheels are turning".

Yes, that is so. A car the was moving in the opposite direction, that is in reverse, would have wheels in concentration to yours.
What you see as "backwards" is apparent velocity. Some backwoods men don't appreciate the difference.
If two cars are at the same velocity, they have the zero KE w.r.t each other? So two passing cars will at some point have zero KE. For how long?

No, I'm not kidding.
And disturbingly, neither is he....

That is disturbing, Captain.

 

[fredriks]

but I say the treadmill itself is false

How can a treadmill be false?

 

[RossFW]

The treadmill is the basis of the windspeed claim and offered as evidence, but I say the treadmill itself is false, and therefore can say nothing either way about the cart. That is easily dismissed from a physical point of view, but its claims are supported by ideas that are metaphorical. That makes it difficult to knock down.

Yes, that is so. A car the was moving in the opposite direction, that is in reverse, would have wheels in concentration to yours.
What you see as "backwards" is apparent velocity. Some backwoods men don't appreciate the difference.
If two cars are at the same velocity, they have the zero KE w.r.t each other? So two passing cars will at some point have zero KE. For how long?

Greg,

Bear in mind this is two months and hundreds of posts of trying to explain his mis-comceptions to him.

Dude, its all yours!!!


ETA:- Could someone point out to me which of the vector diagrams Humber didn't understand where "Metaphorical"??

 

[H'ethetheth]

To save H'eth any more embarrassment, I am not Dutch.

Thanks

If two cars are at the same velocity, they have the zero KE w.r.t each other? So two passing cars will at some point have zero KE. For how long?

Passing cars don't have the same velocity by definition. Velocity is a vector quantity, remember? You're confusing vectors with vector magnitudes.

 

[humber]

In Humber's absence, let me try a very quick summary of his position for you Greg:

Well...

"A belt is not a road."

Expanding on that slightly, I understand that Humber has said he doesn't have any problems with the general concept of a vehicle travelling directly downwind faster than the wind, although he may think that a steady state situation is problematic, and I'm pretty sure he has also said that the spork/JB cart is not one of the vehicles that could actually achieve DDFTTW. I don't recall hearing his views on your tumbleweed device.

Yes, Clive. That is a good summary. The 'belt is not a road', means that the belt does not imply motion. The belt is a moving surface, that may be used to emulate the effects of a car passing over a road (boundary layer generation for example), but not the travel itself.

But the really big issue is that he doesn't agree that testing/demonstrating the cart on the treadmill can be said to be equivalent to the cart running downwind over a real road at the same speed as the "real wind". This is nothing to do with anybody faking videos, just the physics. From memory, for the last 1500 posts or so the main topic has been something to do with which direction some parts of the boundary layer above the belt of the treadmill may moving relative to the belt, and how that could differ from the situation with "real wind" moving over a road.

No. I say the treadmill is conceptually flawed. It is so metaphorical that it is hard to dismiss many of its claims. Criticism can be easily deflected. The boundary flow shows a true physical error, that is an indicator of that conceptual flaw.
On step of the argument, Clive.

Once that is resolved, I suppose it is possible the "discussion" may move on to whether this boundary layer actually has any significant effect on the cart's behaviour or not. At this point I really wouldn't like to estimate how many thousands of posts that might consume.

Is it resolved, Clive? Do you agree that the paddle proves the point? Even if there were room for the numerical adjustment, the contrarotaion at belt and windspeeds remains. On to the next treadmill error, yes.
The cart is not relevant because the treadmill results are false. The treadmill can say nothing either way about the real cart.

Hmmm. Maybe I am exaggerating slightly, because I've just recalled that a decent chunk of the last 1500 posts might have been more about a hobo in a boxcar and whether he could tell whether he was "moving", and whether that was to the left, or clockwise. What is really needed (hint!) is for someone to create a giant map and index so newcomers to this interesting place can explore more easily. Don't forget to read the even longer parent thread! Much important background information and earlier discussions are only to be found there.

Forget to read the even longer thread. All that "Einstein in a box stuff" is not of my doing, Clive. As relevant as cheese.

I think that I have shown at least 3* ways in which "treadmill wind" is not like real wind.
Gravity and friction dependence, the boundary problem, the lack of actual wind power or motion, the way the wheels spin at "windspeed" that contradicts motion, no velocity w.r.t the ground, no significant KE from any "frame". Operator interference, instant acceleration to winspeed, experimental fitting, falsifiability, no ground (the belt is not the road, but the earth), lack of any work and of course the solution to the cart 'balance' claim. Other than that, it's 100% good.

* I have new one. Post later today.

Possibly the best place for you to start (if you don't mind me making a suggestion) would be by posting your thoughts on the validity or otherwise of using the treadmill (as shown in the spork/JB videos on youtube) to test/demonstrate the cart's behaviour when it is moving directly downwind at the same speed as the wind (or very close to it).
Oh, last thought, in some other tangential discussion I think it was also established that "a kite is not a treadmill". I can't remember if Humber actually agreed with that, but Humb probably did.

Yes. Even if imitation is the sincerest of flattery, accept no substitutes.
Humb has the opportunity and motive, but not the means.