Furcifer
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And his notation lives on forever.
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Split Thread The validity of classical physics (split from: DWFTTW)
- Thread starter Dan O.
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And his notation lives on forever.
GregLondon
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They didn't let the lab rats fly the planes, (especially low level lab rats, since I was a lot younger back then) so I never got to actually feel how it handles. Nice to hear from another happy customer though.
I always preferred a simple, direct mechanical connection to my control surfaces anyway. And if it can hover, all the better.
GregLondon
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Oh drat. Fixed it. Thanks, mender.
Back to the kites for a moment: to help clarify whether there is an actual difference in the two scenarios that you proposed, let's extend the length of the kite string, raise the height of the kites as they are flying, and add a cloud layer between the kites and the ground. To observe and record the behavior of the kites, a helicopter with a camera crew is hovering nearby.
The first kite is launched into a 10 m/s wind and the holder of the string is standing on the ground and not moving. The kite goes up over the clouds. When the camera crew reports that they are in position and filming, the kite string is severed right next to the kite and the result is filmed.
The second kite is launched on a day with no wind and the holder of the string is standing on a very long treadmill moving at 10 m/s (or the holder is standing in the back of a truck that is driving along a road at 10 m/s, your choice). The kite goes up over the clouds. When the camera crew reports that they are in position and filming, the kite string is severed right next to the kite and the result is filmed.
Would there be any way that the film crew and/or anyone watching the videos afterward could tell the difference between the first kite and the second kite by what happened after the string was severed?
Bonus question: before the kite string is severed, what is the air speed of the helicopter if it stays exactly in position wrt the kite in scenario#1 and in scenario #2? The same in both cases, different, or opposite?
That's pretty close: at best, it will model what the cart does outside in a perfect wind. Fortunately, modeling what the cart does outside in a perfect wind (no gusts or direction changes) allows a much more precise way of comparing the cart's speed to the speed of the wind to determine if/when the cart matches the speed of the wind (which it sees as still air at that point). In both cases (outside case and treadmill case), the KE change in the air surrounding the cart is the same.
That's how the cart is powered, by the change in KE of the air surrounding the cart. If you have been playing the many-leveled game that RP thinks you are, you should be able to say, "Well done, mender, my work here is finished". If you still insist that the cart would have to be magic to achieve DDWFTTW, well, I'm not sure that anything anyone can say will ever change your mind.
What say you, humber?
The first kite is launched into a 10 m/s wind and the holder of the string is standing on the ground and not moving. The kite goes up over the clouds. When the camera crew reports that they are in position and filming, the kite string is severed right next to the kite and the result is filmed.
The second kite is launched on a day with no wind and the holder of the string is standing on a very long treadmill moving at 10 m/s (or the holder is standing in the back of a truck that is driving along a road at 10 m/s, your choice). The kite goes up over the clouds. When the camera crew reports that they are in position and filming, the kite string is severed right next to the kite and the result is filmed.
Would there be any way that the film crew and/or anyone watching the videos afterward could tell the difference between the first kite and the second kite by what happened after the string was severed?
Bonus question: before the kite string is severed, what is the air speed of the helicopter if it stays exactly in position wrt the kite in scenario#1 and in scenario #2? The same in both cases, different, or opposite?
That's pretty close: at best, it will model what the cart does outside in a perfect wind. Fortunately, modeling what the cart does outside in a perfect wind (no gusts or direction changes) allows a much more precise way of comparing the cart's speed to the speed of the wind to determine if/when the cart matches the speed of the wind (which it sees as still air at that point). In both cases (outside case and treadmill case), the KE change in the air surrounding the cart is the same.
That's how the cart is powered, by the change in KE of the air surrounding the cart. If you have been playing the many-leveled game that RP thinks you are, you should be able to say, "Well done, mender, my work here is finished". If you still insist that the cart would have to be magic to achieve DDWFTTW, well, I'm not sure that anything anyone can say will ever change your mind.
What say you, humber?
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No you don't.
No you haven't.
Poll update:
Does humber really understand physics more than is apparent in this thread?
And the results:
Yes:
Clive: He Understands Much But Excludes Reason.
recursive prophet: but qualified
Semper: Yes, but not much.
humb: Of course he does. In addition to the wealth of information that he has provided you with, I have no doubt that he has comparable expertise in other branches of physics.
NO:
spork: his confusion is legit
subduction zone: only a true believer would keep this nonsense up for 65 pages and over 2,500 posts.
mender: I believe that humber is presenting things as he understands them.
Dan O.: humber doesn't have the background to be faking it.
Michael C.
Fredriks: Humber don't know more physics than it seems to but it is possibly that he to some extent know that everything he says is incorrect but that he like to write nonsense on the internet anyway.
GregLondon: I'm not a gambling man, but I'd wager a sandwich that Humber doesn't know physics more than he has revealed in the thread.
I'm tempted to change my answer. I don't think humber understands physics, but even a random process couldn't possibly be so consistently wrong.
Does humber really understand physics more than is apparent in this thread?
And the results:
Yes:
Clive: He Understands Much But Excludes Reason.
recursive prophet: but qualified
Semper: Yes, but not much.
humb: Of course he does. In addition to the wealth of information that he has provided you with, I have no doubt that he has comparable expertise in other branches of physics.
NO:
spork: his confusion is legit
subduction zone: only a true believer would keep this nonsense up for 65 pages and over 2,500 posts.
mender: I believe that humber is presenting things as he understands them.
Dan O.: humber doesn't have the background to be faking it.
Michael C.
Fredriks: Humber don't know more physics than it seems to but it is possibly that he to some extent know that everything he says is incorrect but that he like to write nonsense on the internet anyway.
GregLondon: I'm not a gambling man, but I'd wager a sandwich that Humber doesn't know physics more than he has revealed in the thread.
I'm tempted to change my answer. I don't think humber understands physics, but even a random process couldn't possibly be so consistently wrong.
You wrote:
No, you have that quite wrong.
What it means, Fredriks, is that I took the time and effort to increase the level of explication while narrowing the focus. That is, I reduced the information density to meet your needs. I dumbed it down.
Then:
This, and the one word replies you gave to my efforts, show that you see things only as black or white and have no need of learning, while publicly displaying contempt for the idea that you could be wrong.
That's why.
No, you are not.
Through the looking glass, dimly.
Thanks, must people would try to make sense in the first step instead of starting to write incoherent nonsense and later dumb it down (so it make at least some sense).
Still your post showed what might happen when the lord flies the kite standing on a treadmill. You clearly explained that it is going to work so your case against walmart is clearly dead. The poor Lord might have trusted you.
Modified
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I don't think the usual meaning of the word "understand" applies in this case.
Must be confusing not being able to distinguish between all them there 'Thatta ways".
Where 'everyone' is but you alone.
Like a bull carrying it's own china shop.
Your example shows that the idea is still giving you a singular headache.
You have given an example of impulse energy or momentum transfer. "Inertia", like a number of terms in physics such as "centre of gravity", is notional.
Little grey cells to 'on':
Being 'dragged back with the belt', implies a static force obtained only by being attached to the belt. That is what I meant, and the only possible stable condition for that mode of operation.
Now, please tell me how the cart can stay on the belt, in any other state than "windspeed". Good luck.
Delivered in genuine '49er patter.
So close, poor thing.
Calculus is not for you then.
Did it hurt so much that you need to impute it to others?
Yes, quite a difference, but with a twist. You think they are the same.
Shoot
Creative to the max. You can find lots of Tranny's in Bangkok, but if you prefer the homegrown product...
A regular McGuyver, though he is less boastful.
Perhaps when the smoke cleared, the car was still on the dyno?
But who can say if you can't see it.
Impeccable instrumentation.
No way, Dude.
Charity?
You controlled but some of the variables. Is that why you think wind and treadmill are alike?
You have just explained why bicycles have gears, and how it is possible to gain more power if the engine is better matched to the load.
Perhaps 'maximum power theorem'?
Good. Now it's your turn
Let now us investigate that claim
No, see what you've done? You replaced my remarks with yours. That causes a bad reaction within the humber.
From treadmill side, both Anubis and balloon are moving to the left. When released, that is also true for a short period while the balloon decelerates. From that point, the balloon is essentially static, ( w.r.t the treadmill side if you must) but Anubis is still moving, giving impressionable observers (but not he), that the balloon is in moving away from him. The balloon soon falls to the belt, and remains at a fixed distance from Anubis, and the very source of his displeasure.
Once released, there is no air motion over the kite. It is in still air. Gravity pulls it to the belt.
No, that is not correct. Kites can fly without string. A simple fact.
A kite may fall to the ground in wind because it becomes unstable (the string can control the kite's attitude to the wind and so forth) is not the same as a dead drop in still air. Anubis is quite a guy. You should at least credit him with the ability to choose an appropriate kite.
There also the futility of not recognizing the difference between wind and forced motion through the air, and then combining the two to make your case. I let others to take my kite up.
You need better spectacles, and less focus on yourself.
John Freestone
Graduate Poster
Yes, as has been observed many times, that is one of the reasons testing on a cart is very useful. Now that humber's air-flow objection comes down to "turbulence" (which again means he's backtracked and won't be going on about the directions all being the wrong way round again, because we've proved that to be nonsense too clearly for him to get away with it...) he is citing one of the experimental advantages that we already know about as the reason why the treadmill is "false". He also, of course, has other objections, like which part of the system is providing the power to cause the relative motion, which will probably run until he's dead.
Well, the last bit's true. But he'll want it several ways at once: it's not magic, it hasn't been demonstrated yet, it doesn't work the way idiots like us think, and he could build one that does it in a jiffy. Funny we're still waiting for the plans.
Oooh yeah, can't wait to find out.
Yes, precisely. And then there's the inverse relationship between his eloquence and the starkness of his self-contradiction. The closer his back is to the wall, the more the Telly-Tubbies Zen comes out, mixed with new red herrings, misused terms and unsubstantiated humberist dogma.
My answer is "yes, with reluctance" (since I wasn't clear before and Eliza wasn't much help!). This is the way some people learn stuff. I think later on when the dust has settled, much of what we've been teaching him will be his normal understanding, background knowledge he probably believes he's always possessed. He might even end up teaching a bunch of students it, musing about how counterintuitive it is and how ordinary people tend to believe in absolute motion and kinetic energy. He might sketch bunnies on treadmills with anemometers, and demonstrate that he understands it just fine. He could do that now. He refuses to 'understand'. He just can't ever be wrong or have been wrong, and therefore mustn't change his mind until he's changed his interlocutors.
It's a funny old poll, cause it's unlikely we'll ever find out who's right. Still, interesting to see who thinks what.
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Now, look what you have done SD. An inexhaustive list includes:
(1) Loaded the question with your preconceived notions
(2) Not asked the same question of yourself
(3) Assumed that this problem has anything to do with that level of scientific endeavor
(4) Apart form a few details, cognition or perception would be a more appropriate category than physics for the nature of the problem.
(5) Assumed that said laureates would agree with you, and not me.
(6) Still appealing to authority, rather than logic or reason or your own mettle.
(7) Turned a complex matter in to a binary decision, where the answer is judged by incredulity or social norms....
Tsk Tsk.
Phasers set to stun.
John Freestone
Graduate Poster
No, he didn't do any of those. He asked you to "suppose...xyz" and say how you would respond. It is your lack of logic and imagination that is being demonstrated, along with the reluctance to consider this as a possibility.
We know the real answer: you'd tell them they were wrong, with some waffle ending "QED", and tsk tsk at them for being so stupid.
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