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Mess with your minds: A wind powered craft going faster than a tail wind speed.

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electrodacus:

--- Quote from: ejeffrey on August 31, 2021, 04:15:23 am ---
Here you go.  The setup is a little janky, but clearly demonstrates the effect.  The right wheel rotates ~2.5 times for every rotation of the left wheel.  I don't have a treadmill so I used a piece of paper which I slide back and forth under the right wheel to push on it.  I can push with the paper "treadmill" in either direction and the cart moves in the opposite direction: towards the application of force.  This is due to the gear ratio, and the formula which I posted above that you ignored and claimed had to be wrong without describing why.  No slippage is occurring on the wheels or the belt.  It works at very low speeds or moderately fast speeds, if I go faster it obviously starts to slip.

Apparently the eevblog forum won't allow video embeds regardless of size, so sorry about the imgur link:

https://imgur.com/a/lTqAFg6

--- End quote ---

Sorry a piece of paper is not a treadmill but you can build a simple treadmill made of paper. The paper will need to be glued in a loop and then use two cylinders with axis fixed to the table.
The reason the piece of paper is not a treadmill is because the paper moves relative to the ground/table where a treadmill will not do that. It is like powering OFF a treadmill and push it under the vehicle.
The paper will not push against the generator wheels it will just slide under while on a treadmill the treadmill will push against the vehicle as it is anchored to the ground is no moving relative to the ground.
You will just need to build as basic of a treadmill as you want to see the big difference between your paper and a treadmill (can also be made out of paper).

electrodacus:

--- Quote from: Brumby on August 31, 2021, 04:21:31 am ---We are still talking about "motor wheels" and "generator wheels"....??

--- End quote ---

Yes one of the wheel will drive the other there is no other way. If you prefer different names than generator and motor I'm OK with that.

Brumby:
Nomenclature is not the problem.  It's the use of two 'sets' of wheels - it is completely invalid for the mechanism being debated.

electrodacus:

--- Quote from: Brumby on August 31, 2021, 04:29:35 am ---Nomenclature is not the problem.  It's the use of two 'sets' of wheels - it is completely invalid for the mechanism being debated.

--- End quote ---

Are you saying a propeller is something other than equivalent of a wheel but for a gas or liquid ?
A wheel is more efficient than a propeller so if anything my setup with wheels only gives you an advantage.
The point of using just wheels is to have a better intuition of what happens as air is invisible to human eyes and propeller is a bit magical for some.

Brumby:
But two 'sets' of wheels is not an appropriate analogue.

Excluding the propeller and it's interaction with the air is as relevant to this discussion as me saying I want to test a space suit by jumping into a pool with it.  Whatever else it might simulate, such an exercise does not reflect the real world environment.

Your wheels argument does not reflect the real world environment governing the blackbird AT ALL.

Continuing to do so simple underlines your ignorance, stubbornness and, dare I say (what is increasingly difficult to dismiss) your delusion.

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