Merged DDWFTTW in a “Real” Wind

[Llyricist]

Humber doesn't understand leverage, he doesn't understand a force can be applied that is both torsional and translational. He thinks Newton's third law applies to input and output forces of levers (not to mention other simple machines). He thinks gears cannot be coaxial, because gearing only affects rotational speed (see his understanding of Newton's third above).

He acknowledges the concept of airspeed while dismissing the concept of air distance.

He thinks the fact an airfoil changing the direction of airflow causes lift, means that a change in the wind direction will cause lift.

onandonandonandon.

 

[humber]

Humber,

What would convince you athat you are wrong?

You find a fault in the math, that says I am wrong.

The cotton reel has nothing to do with the cart, which that is a sham because the trail evidence says so.
But it is embarrassing for the Illuminati if they can be shown to make such basic errors.

 

[Jack by the hedge]

Flip the reel over and hey presto, the other version of the thing with no advantage at all.

Remember that I said the curious thing was that people disagreed about what would happen? Well I'm sitting at my desk with an empty wire-wrap bobbin and a piece of string and - guess what? With the string looped over the bobbin, it moves in the same direction the string moves, but slower than the string. If the string is looped under the bobbin, it moves in the same direction the string moves, but faster than the string.

Who'd have thought it, eh? Oh, yeah - me. And almost everyone else. Not whoever came up with that daft annotated diagram, though.

Then the opposing force will be high. So the idea is to add more opposing force to make the reel go faster?

The idea is that the bobbin can travel faster than the string which drives it.

Then you can put the numbers in the math, but you will have trouble with the gears. The video of the reel and paper, is an example of sleight of hand.
The paper is lifted and the reel rolls along it.

What trouble with the gears? There is no perceptible slip with my bobbin. If it had gear teeth preventing any slip at all, nothing would change.

I never saw that video with a reel and paper. Your idea of looping the string over the reel prevents any such "sleight of hand" though, doesn't it?

 

[A.T.]

The geared version is going to be bad. The most likely outcome is that...

LOL @ "most likely outcome"

A geared version that cannot slip has a certain outcome. If you knew basic geometry you would not have to guess.

 

[Modified]

Somewhere in Cartville, there is a musky catacomb. Behind a pile of skulls, their sits an earthenware pot containing "things humber has said."

That must be some pile of skulls.

 

[humber]

I have a geared version: it works perfectly smoothly. It's made with Fischertechnik parts and it's not so pretty as the simple cotton reel and paper. Maybe I'll make a video of it someday, but not for humber's benefit: it wouldn't convince him anyway. He'd say it was an illusion, that something else was happening, that it isn't what's represented in the diagram, whatever.

Fatuous. The video "experiments" you have made, show that your claims are bunk, and the result of forcing the desired outcome by manipulation.

 

[jduffy77]

"In effect the higher wind speed before the measurement period got the craft close to its equilibrium speed more quickly but it would have gotten there if the wind had stayed at exactly 10 mph for the entire run."

Voodoo.

No, common sense. An obviousity.

 

[humber]

That must be some pile of skulls.

Each containing more brain matter than the typical Carteer.

There is negative drag and cavitation in gases. There are also negative frequencies, that turn up as a result of digital signal processing.
It's hard to conceive of what a negative frequency may be.

ETA
Hold the reel in the hand using a spindle through the hole. Pulling the thread from below, always results in CCW rotation.
The hand provides a restraining force that ensures that. A force opposing the force of the thread.
Rolling friction always operates to decelerate a wheel, so works counter to the direction of rotation. When that force is positive so in the direction of the hand
the reel rolls in the direction of the hand, so opposite of the held case. When its the other way, the reel rolls away.
It's that balance which determines which way it moves.

 

[Jack by the hedge]

Fatuous. The video "experiments" you have made, show that your claims are bunk, and the result of forcing the desired outcome by manipulation.

I'm just rolling this bobbin back and forth on my desk for the simple pleasure of watching you being wrong.

 

[Llyricist]

Humber doesn't understand the difference between traction and rolling resistance.

 

[Jack by the hedge]

Hold the reel in the hand using a spindle through the hole. Pulling the thread from below, always results in CCW rotation.

Tie the reel to an anvil, drop it off a boat and it'll sink. Put it on a Saturn V and it'll go into orbit.

Different experiment is different. <shrug>

 

[CORed]

Humber doesn't understand the difference between traction and rolling resistance.

The list of simple physical concepts that humber doesn't understand is very long, if not infinite.

 

[Jack by the hedge]

yeah, I could reduce my post count by just saying

humber doesn't understand how the world works.

By now, humber will have found a bobbin and a piece of string, and he'll be trying to figure out what trick we've pulled to make them behave so strangely.

 

[humber]

I'm just rolling this bobbin back and forth on my desk for the simple pleasure of watching you being wrong.

And? The results are always due to bad experimantal control, or poor analysis of the results. That applies to the cotton reel videos and the BB trail.

Another reel video was produced, where again poor understanding and random variables produced the desired outcome. That too is exactly how the BB trial was conducted. Keep trying until a "win" occurs. That is not how its done.

A spool of wire was dragged across the floor, but the author did not notice or consider another game naughty reels get up to.

At each instant, the point at which the reel is in contact with the surface is stationary, and may be seen as an axis of rotation. The entire reel could turn around that point.

The force F1, tends to produce a moment that tends to turn the reel CCW, in the direction (1), so it moves towards the hand at F1.
If the thread is inclined as in F2, the moment produces tends to turn the reel clockwise ins the direction of (2) and the reel moves away from the hand,
But, if the wire is stiff as it was in the video, the reel will rock back and forth on that contact point with the ground. It's common to retrieve a spool of electrical wire that has run away, by pulling on the wire at an angle.

 

[humber]

You have rediscovered fire.

 

[humber]

Your biggest mistake is to think only of velocity. That was sold to you by way of "Galilean Transforms". But the wind is not a "vector", and there is more to the problem than "net force" and peak speed.

A puzzle.

A cyclist may develop a thrust of 100N. Let's say the opposing force is 50N ,and the total mass of the rider and bike is 100Kg

a = net force/mass
= 100N -50N/10kg = 0.5ms-2

So after 20minutes his velocity will be
v =a*t
=0.5ms-2*1200s = 600m/s.
The speed of a bullet.

What is wrong?

 

[Jack by the hedge]

And? The results are always due to bad experimantal control, or poor analysis of the results. That applies to the cotton reel videos and the BB trail.

I'm not watching a video. I'm watching a live show of you being wrong.

It's common to retrieve a spool of electrical wire that has run away, by pulling on the wire at an angle.

I find that just pulling on the wire any old how works fine.

A dropped spool tends to run away with the wire paying out from under the spool. Since the spool rolls away faster than it pays out wire, you only need to hang onto the wire and it'll go tight, stopping the spool.

 

[humber]

I'm not watching a video. I'm watching a live show of you being wrong.



I find that just pulling on the wire any old how works fine.

If you make the reel with one turn as shown, when the reel moves to the right, the right hand will move further than the reel, perhaps using force F.
If you conspire to move it the other way, perhaps by using wheels to "reverse" the force, you need a net force in the other direction -F. That will mean F will double. You can't feel that with a ruler.

A dropped spool tends to run away with the wire paying out from under the spool. Since the spool rolls away faster than it pays out wire, you only need to hang onto the wire and it'll go tight, stopping the spool.

It rolls because it has gained KE from acceleration under gravity as it falls.
See? You need to control all variables, or you are home to Mr Cock-up.

 

[Jack by the hedge]

If you make the reel with one turn as shown, when the reel moves to the right, the right hand will move further than the reel, perhaps using force F.

If the cord is wrapped so that it's pulling at the top of the reel then yes, the hand moves faster than the reel. If you flip the reel over so the cord is pulling at the bottom then the reel rolls faster than the hand. Look - I'm doing it now.

If you conspire to move it the other way, perhaps by using wheels to "reverse" the force, you need a net force in the other direction -F. That will mean F will double. You can't feel that with a ruler.

Sadly I have no idea what you're talking about. I may not be alone in that regard.

It rolls because it has gained KE from acceleration under gravity as it falls.
See? You need to control all variables, or you are home to Mr Cock-up.

Sadly, I am unable to control gravity. Happily that aspect of the problem is irrelevant to the principle that a rolling reel pays out wire slower than it travels.

 

[CORed]

Doh. Make the table glass, and you can have an "observer" give you the same answer.
When you try it as shown in the upper photo, things will not go well.
But, that is what you are hoping with the rack and gear.
When tensioned, the best you can do is drag the reel at the speed of the hand.


If you use one hand and allow the reel to turn, as in the lower photo ( I used a strip of leather but a shoelace should work), it too moves at the speed of the hand, but rolls.
(The bolts give the reel some mass, otherwise it's hard to control.)

[qimg]http://www.internationalskeptics.com/forums/attachment.php?attachmentid=21497&stc=1&d=1300899210[/qimg]




Then don't give counter-arguments that employ grativty
It's a pity that Carteers were not so critical of Spork's nonsense. Even a sledge-hammer of rampant experimental errors and internal inconsistencies has not dampened faith.

Mmm...maybe it's just me, but I am getting the impression that the idiot may not be Dan Kammen.

Amazing: You went to the trouble to rig the spool and string and take still photographs, but didn't actually perform the experiment, or you did and lied about, or somehow managed to misinterpret the results.