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

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cbutlera:

--- Quote from: electrodacus on September 01, 2021, 04:36:39 pm ---No when there is wind the particles move in the same chaotic way but on top of that there is a net movement in a particular direction and that will be called wind.

--- End quote ---
That is right, but the wind speed in all the circumstances that we have been discussing is a tiny fraction of the average individual speeds of the air molecules.


--- Quote from: electrodacus on September 01, 2021, 04:36:39 pm ---When I think in my head I imagine the vehicle still moving and the road is what is stationary so I do not modify the frame of reference.

--- End quote ---
That is fine when considering the interaction between the wheels and the stationary platform, but when considering the interaction between the other wheels and the treadmill, the stationary frame of reference is not the best choice.

However you can still do it, as long as you remember to include the work done by the treadmill on the vehicle, as well as the work done by the vehicle on the treadmill.  What you seem to keep doing is forgetting the work done by the treadmill, and then concluding that conservation of energy prevents the vehicle from moving to the right.

Going back to my aircraft thought experiment.  The aircraft is travelling at 200 m/s, I get out my seat and walk forwards at 1 m/s, I weigh 70 kg.  How much energy did I have to expend to accelerate from 200 m/s to 201 m/s in the frame of reference of the ground?  From the ground frame of reference my kinetic energy has increased from 1,400,000 joules to 1,414,035 joules. A difference of 14,035 joules.

electrodacus:

--- Quote from: cbutlera on September 01, 2021, 05:28:25 pm ---That is right, but the wind speed in all the circumstances that we have been discussing is a tiny fraction of the average individual speeds of the air molecules.

--- End quote ---

That thermal jiggling of the air molecules is not useful to extract energy from. When vehicle is at same speed as wind speed it can no longer extract any wind energy is the same as a non moving vehicle in a day with no wind or indoors.
The treadmill experiment was done indoors so no wind energy available and and still it showed the vehicle moving forward against the treadmill direction clearly meaning that stored energy was involved. But people instead of getting to this proper conclusion decided to think that energy from the treadmill can be used to push against air and be able to move forward and if that was to be true it will violate the conservation of energy (obviously that is not true).


--- Quote from: cbutlera on September 01, 2021, 05:28:25 pm ---That is fine when considering the interaction between the wheels and the stationary platform, but when considering the interaction between the other wheels and the treadmill, the stationary frame of reference is not the best choice.

However you can still do it, as long as you remember to include the work done by the treadmill on the vehicle, as well as the work done by the vehicle on the treadmill.  What you seem to keep doing is forgetting the work done by the treadmill, and then concluding that conservation of energy prevents the vehicle from moving to the right.


--- End quote ---

Any experiment where my diagram is respected will show that vehicle can not move from left to right. There is not even one experiment showing that.



--- Quote from: cbutlera on September 01, 2021, 05:28:25 pm ---Going back to my aircraft thought experiment.  The aircraft is travelling at 200 m/s, I get out my seat and walk forwards at 1 m/s, I weigh 70 kg.  How much energy did I have to expend to accelerate from 200 m/s to 201 m/s in the frame of reference of the ground?  From the ground frame of reference my kinetic energy has increased from 1,400,000 joules to 1,414,035 joules. A difference of 14,035 joules.

--- End quote ---

What do you mean by aircraft ? For me an aircraft will be something that travels in air not on ground so something like an airplane.
I can not imagine you getting out of an aircraft and then walking.
But say you are referring to an airplane driving very close to ground and then you get out of that (it will be very painful) as that 200m/s speed of aircraft is relative to stationary ground so if you get out of the airplane as soon as you touch the ground all you kinetic energy will be reduced close to zero in seconds so you will likely not survive let alone be able to walk.
Have you ever got down from a moving vehicle like maybe a train ? It will need to move very slowly so that you are able to absorb all that change in kinetic energy else you will get hurt.

I have mentioned a more appropriate analogy of what you are trying to describe.
That will be a road with two lanes where one lane is fixed so no speed and one lane moves forward (like the surface of a treadmill) at a certain speed say 10m/s and you can call this moving lane wind speed.
Now you have an non powered vehicle that can have access to both lanes and you want to drive faster than 10m/s but it will be impossible.
Best you can do have the entire vehicle moved on the 10m/s lane and so vehicle travels on that lane at same speed (like a hydrogen balloon carried by the wind).
Trying to have part of the vehicle (some wheels) on the stationary lane and part of the vehicle on the moving lane will just result in vehicle driving slower than 10m/s relative to the stationary lane.
   

PlainName:

--- Quote ---Any experiment where my diagram is respected will show that vehicle can not move from left to right. There is not even one experiment showing that.
--- End quote ---

There are at least two, and you've posted one yourself. I doubt if there will be another because it's obvious you will find some issue that allegedly negates the experiment.

How about you show the experiment that proves your hypothesis?

cbutlera:

--- Quote from: electrodacus on September 01, 2021, 06:50:06 pm ---What do you mean by aircraft ? For me an aircraft will be something that travels in air not on ground so something like an airplane.
I can not imagine you getting out of an aircraft and then walking.
But say you are referring to an airplane driving very close to ground and then you get out of that (it will be very painful) as that 200m/s speed of aircraft is relative to stationary ground so if you get out of the airplane as soon as you touch the ground all you kinetic energy will be reduced close to zero in seconds so you will likely not survive let alone be able to walk.
Have you ever got down from a moving vehicle like maybe a train ? It will need to move very slowly so that you are able to absorb all that change in kinetic energy else you will get hurt.

--- End quote ---

My apologies, but I thought it was obvious. I am a passenger in a normal aeroplane flying at normal cruising altitude at 200 m/s.  I stand up from my seat and walk down the aisle of the aeroplane towards the front of the aeroplane at 1 m/s, relative to the aeroplane.  I weigh 70 kg.

To an observer on the ground (using the ground frame of reference), by getting up and walking along the aisle, I have accelerated from 200 m/s to 201 m/s. To this observer on the ground, I have increased my kinetic energy by 14,035 joules.  Where did this energy come from?

electrodacus:

--- Quote from: dunkemhigh on September 01, 2021, 07:06:27 pm ---There are at least two, and you've posted one yourself. I doubt if there will be another because it's obvious you will find some issue that allegedly negates the experiment.

How about you show the experiment that proves your hypothesis?

--- End quote ---

That is because you do not understand the difference between my diagram and a flipped vehicle.  The person that posted the video needed to flip the vehicle else if is as shown in my diagram it will not work so it will be unable to show what it thinks it represent.
I guess you are referring to that treadmill experiment where motor wheel where on the other side of the generator wheels compared to my diagram.
While you think flipping the vehicle has no consequence the real consequences are huge as one can move in any direction and the other (the one in my diagram can move just from right to left).
That guy can easily flip the vehicle and show that is not working the same way but he has not done that.
I do not have any wheel based toys as I will have made a short video. Also me doing a video even if I show it is now working you will think I did something to trick you thus best thing is one of you to do the experiment.
One of you showed the vehicle and paper video and is not much to glue a piece of paper in a loop and put that on two cylinders then move that treadmill my hand. The cylinders of course will need to be fixed to the table or whatever surface the motor wheel stand on. 

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