phunk
Illuminator
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And in order to wind on to the reel, the reel has to outrun the string pulling it.
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Merged DDWFTTW in a “Real” Wind
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And in order to wind on to the reel, the reel has to outrun the string pulling it.
Modified
Philosopher
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You keep changing the claim to try to weasel out of admitting you were wrong. You said multiple times that the reel could not move faster than the string. Then you said that it could, but only due to an "impulse". Just a few posts ago you said "The thread can't pull it, unless it slides". All of that is clearly wrong.
No. You won't get away with that Modified, because I have said the same thing many times, and you can find drawings and the calculations posted 2 years ago that support that claim.
Want to know why it has taken so long?
http://talkrational.org/showthread.php?p=1349856#post1349856
He chose 'f '
I am making the point about it being dynamic, because that is the underlying problem. It means amongst other things, that the length of the string does not matter, regardless of which way it goes. It will never work, no matter what.
But last and definitely not least, how poor experimental control and assumption lead to errors and irrelevant outcomes.
In a way, but you all still do not see the consequences of the math.
Yes, I am beating you over the head with it, but then again. I have to take lot.
But it's the key to understanding why, in general, the idea has no merit whatsoever. Looking at it, and doing small experiments to demonstrate the obvious, does not tell you why that is.
You seem to think there is some value in "seeing" problems by way of "intuition", well math is at least another way. Not all engineers are good at math, but in the end, that rules over perceptions and seat-of-the- pants instinct. It's not that the latter does not "work", but that it often doesn't.
Answer the "puzzle" about the bicycle, and you will see why.
The last one should be 5 inches, I Ratant, but the reel moves no further than the hook. Voila!.
ETA:
It follows. The distance an object moves, is defined by how far its centre of mass moves.
One only need consider how far the axle moves.
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Maurice Ledifficile
Lost in translation
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No free lunch here
I have been lurking a long time and never thought I’d post anything, but I have to stick my nose in this one. Here’s what I gather:
Yes, Humber, it’s true. The spool catches up to the hand, therefore it is moving faster. But let’s imagine we are pulling a giant spool on a railroad track, with a rope over the shoulder. Pulling from the underside of the spool, you will only be able to pull about half the weight you could pull with a hook. This “extra” speed comes at a cost. No free lunch.
As to the kart, the propeller is powered by the very wind it is resisting (wind moves cart, wheels turn, propeller turns). That hardly sounds like it can generate much of anything. The kart would be faster without. I have 0% confidence in the record run’s validity. There. Put them apples in your pipe.
I have been lurking a long time and never thought I’d post anything, but I have to stick my nose in this one. Here’s what I gather:
Yes, Humber, it’s true. The spool catches up to the hand, therefore it is moving faster. But let’s imagine we are pulling a giant spool on a railroad track, with a rope over the shoulder. Pulling from the underside of the spool, you will only be able to pull about half the weight you could pull with a hook. This “extra” speed comes at a cost. No free lunch.
As to the kart, the propeller is powered by the very wind it is resisting (wind moves cart, wheels turn, propeller turns). That hardly sounds like it can generate much of anything. The kart would be faster without. I have 0% confidence in the record run’s validity. There. Put them apples in your pipe.
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Maurice,
You understand that the propellor is geared to the wheels? That the wheels turn, and THAT turns the propellor?
No, it doesn't, it's counter-intuitive.
is intuition always the best way to solve problems? Do you have an alternative explanation to the carts observed performance?
You understand that the propellor is geared to the wheels? That the wheels turn, and THAT turns the propellor?
No, it doesn't, it's counter-intuitive.
is intuition always the best way to solve problems? Do you have an alternative explanation to the carts observed performance?
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Maurice Ledifficile
Lost in translation
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That is what I said. The wind is what powers the propeller, via the wheels. No free lunch.
What is your definition of wind?
It is the fact that the wheels move over the GROUND that moves the propellor. It is fact that the prop then accelerates air which is moving faster than the ground in the direction of travel (wind) which provides the energy.
No free lunch. No wind, no movement.
You do understand that a sail driven craft can go downwind faster than the wind on an angle to the wind? Is THAT a free lunch?
It is the fact that the wheels move over the GROUND that moves the propellor. It is fact that the prop then accelerates air which is moving faster than the ground in the direction of travel (wind) which provides the energy.
No free lunch. No wind, no movement.
You do understand that a sail driven craft can go downwind faster than the wind on an angle to the wind? Is THAT a free lunch?
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Maurice Ledifficile
Lost in translation
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Data falsification? Who cares. Whatever it is, I'm through with this nonsense. Okaybye.
EHocking
Penultimate Amazing
Are you refuting that the above is an incorrect summary of events of the BUFC 2nd Run video...... or are you merely wishing to ignore the evidence of the video?Yeah, sure.Originally Posted by EHocking
Strawman.
That is obviously not the videos that I referred to in my post.
Which video do you take this from and at what time stamp?
As per my previous post, , the streamers in the 2nd video linked stay in the direction of "downwind" before the start of the run (0:18 to 1:23 mins) and remain so until about the 3:03min mark where the call from the pursuit car sounds like they're saying cart(?) speed is 13.9mph, then 15, then 19mph.
Andrew Wiggin
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Nice first posts. Welcome to the forums. I can see you'll go far here. </sarcasm>
This is no different than humber does; misunderstand, argue from ignorance, and when faced with facts alledge conspiracy, fraud and professional misconduct. NALSA had a vested interest in detecting fraud, and plenty of experience in verifying exactly this sort of performance. This wasn't fundmentally any different than the record set by Greenbird, other than it being a craft with surprising performance and a different sail. You argue, but in the end, to quote Galileo, Eppur si muove!
Well, yes, but there is no telling a Carteer by one single yet show-stopping argument. Work in = work out. The "catching up" is just an additional practical difficulty. Also, it is better to put small wheels on a body, and turn them, rather than rotate the entire mass of the body.
It's a proposal for perpetual motion, which uses the ruse of saying "it looks like it is, but isn't" .The trial was a farce, and influenced by the buddy network that surrounds Sportvision's Stan Honey and his boats.
The wind is variable, right? Once the streamer flips to >WS, it never goes back, which is to suggest that not only did it get to WS, but the peak speed of the wind, before it did that. Streamers are dominated by the local pocket of air die to motion of the cart. The true wind could be blowing from anywhere.
The streamers have been selected and tied in a biased manner. In another video, you can see how they bend OVER the horizontal bar when pointing to the front. (when stationary.)
All things lead ot Rome for the Crankies. The cart works, it just does, so any fiddling, lying, deception or underhandedness, is quite OK.
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One NALSA rep, plenty of zealots from TAD, Volvo Racing, Journalism and Joby.
It would take a lot to object to that. This thread is a guide to how difficult that would be. Spam all magazines, blogs etc until some bite.
None whatsoever. All (two!) record attempts measure only the speed of the cart wrt the ground using GPS. Nothing specific to the wind, and the same as a car on the road.
Oh that tired Galileo Cliche. Perhaps he also said "I...how you say...like-a-pizza!"
Greenbird may wander as it pleases. It is expected that the pilot will take best advantage of the wind. DDW means ddw,
Andrew Wiggin
Master Poster
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Ah yes, the old 'humber method'. It works for you, at least. For some value of work. I guess everyone needs a hobby, and disproving this, in the face of all evidence to the contrary, is yours.
Doubtful. The burden of proof is upon you, and the data denies the claim, not supports it. The RMS value of the wind deviation is at least 20 degrees, but Spork will not supply the 60MB of data so "freely and openly" given to NALSA to others, which may allow his homework to be checked.
For the 10 seconds of data that is known, the deviation is not 4 degrees, but 11degrees. Depending on which of the two possible datums are used, ( the reference is circular - the wind direction is compared to the cart which is compared to the wind), then the difference of cart and wind is 15 degrees for that same period.
It is not technically correct, nor even commonsense to average the deviation. By that measure, you could drive to work (+)and then drive home (-) and say the average distance traveled is zero. Any jibing boat may produce an average of close to zero.
EHocking
Penultimate Amazing
No response to this?
EHocking
Penultimate Amazing
I've just viewed the Jenkins video.
You are mistaken.
That is not a streamer attached to the front aerial, it is (probably) a rigid aerial component and does not swivel at all through the entire run.
It is not a streamer.
Care to discuss the Run 2 video that I was actually talking about, that does show the three red/orange streamers?
It's a cart tacking the wind, for a short time, just like at the trail.
The difference is that you like to see it as magical.
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