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Electroboom: How Right IS Veritasium?! Don't Electrons Push Each Other??
electrodacus:
--- Quote from: Naej on July 20, 2022, 11:10:56 pm ---
--- Quote from: electrodacus on July 20, 2022, 10:55:48 pm ---Newton 3'rd law applies to F1 and F2 the same way it applies to F3 and F4
--- End quote ---
Sure, but what does it say?
--- End quote ---
What do you mean but what does it say?
If the red box was perfectly slippery then F1 will be zero (that is after mass of the vehicle was accelerated from right to left).
Even will far less than perfect slip on the left wheel (just needs to slip before the right wheel has the chance to do that) the vehicle will just slide from right to left as I demonstrated here https://odysee.com/@dacustemp:8/stick-slip-removed-from-front-wheels:0
gnuarm:
--- Quote from: electrodacus on July 20, 2022, 10:55:48 pm ---
--- Quote from: gnuarm on July 20, 2022, 10:05:10 pm ---I've seen it many times. I can draw it with my eyes closed.
--- End quote ---
I'm curious what you mean by that.
Can you draw that in your mind or on a piece of paper ?
--- End quote ---
Either
--- Quote ---If you can visualize that in your mind are you able to move one of the wheels and see how it affects the rest of the system ?
--- End quote ---
Yes, I don't typically draw things on paper because that is very, very limiting. I see them in my mind and visualize how the operate. In this case, I needed to attach some numbers to the pulley and wheel sizes to see which ratio was larger. As it turns out, the wheel at F2 will turn more slowly, but with more force than the wheel at F1. F1 and F2 are related by the leverage of the system, not Newton's laws...
--- Quote ---Maybe if you can imagine then imagine the wheels having spikes in the treadmill for the wheel on the right and in to the red box for the one on the left straight down.
This way wheels can not slip. Do you think anything can move now ?
--- End quote ---
Of course it can. The wheels will turn according to the ratio of the various components and the car will move correspondingly. In fact, that is the only way to properly understand what is going on. If you move the treadmill to the left, the wheel at F1 will turn clockwise making the wheel at F2 turn clockwise, moving the car to the right.
The why I picture this more easily, is to imagine the treadmill is free wheeling and moving the car to the right. Both wheels turn clockwise and the treadmill moves to the left because the right hand wheel turns faster than the left hand wheel.
--- Quote ---The treadmill will just stall unless is powerful enough to break those spikes.
Newton 3'rd law applies to F1 and F2 the same way it applies to F3 and F4
--- End quote ---
I'm sorry you don't understand simple mechanics. Newtons law does not relate to forces at different points. This is why you are so confused. If F1 and F2 were always the same magnitude, but opposite directions, it would never move at all. When you push on something, it moves because the opposing force is from inertia, which is another way of saying "acceleration". That is an example of Newton's 3rd law. Pushing on an fixed object is another example, where you push on the object and it pushes right back. In all cases, the forces are on the same point, in opposite directions.
You think F1 and F2 are related, being the same magnitude and opposite direction because of some mysterious natural phenomenon transmitting the forces to one another. This is not Newton's law. It's also not true. Newton's law says the treadmill pushes on the wheel and the wheel pushes back on the treadmill. F1 and F2 are coupled through the mechanical leverage of the pulleys, etc.
Naej:
--- Quote from: electrodacus on July 20, 2022, 11:17:58 pm ---
--- Quote from: Naej on July 20, 2022, 11:10:56 pm ---
--- Quote from: electrodacus on July 20, 2022, 10:55:48 pm ---Newton 3'rd law applies to F1 and F2 the same way it applies to F3 and F4
--- End quote ---
Sure, but what does it say?
--- End quote ---
What do you mean but what does it say?
If the red box was perfectly slippery then F1 will be zero (that is after mass of the vehicle was accelerated from right to left).
Even will far less than perfect slip on the left wheel (just needs to slip before the right wheel has the chance to do that) the vehicle will just slide from right to left as I demonstrated here https://odysee.com/@dacustemp:8/stick-slip-removed-from-front-wheels:0
--- End quote ---
Oh so what you mean by "Newton's 3rd law" is Coulomb friction. I see.
electrodacus:
--- Quote from: gnuarm on July 20, 2022, 11:40:30 pm ---
Yes, I don't typically draw things on paper because that is very, very limiting. I see them in my mind and visualize how the operate. In this case, I needed to attach some numbers to the pulley and wheel sizes to see which ratio was larger. As it turns out, the wheel at F2 will turn more slowly, but with more force than the wheel at F1. F1 and F2 are related by the leverage of the system, not Newton's laws...
Of course it can. The wheels will turn according to the ratio of the various components and the car will move correspondingly. In fact, that is the only way to properly understand what is going on. If you move the treadmill to the left, the wheel at F1 will turn clockwise making the wheel at F2 turn clockwise, moving the car to the right.
The why I picture this more easily, is to imagine the treadmill is free wheeling and moving the car to the right. Both wheels turn clockwise and the treadmill moves to the left because the right hand wheel turns faster than the left hand wheel.
I'm sorry you don't understand simple mechanics. Newtons law does not relate to forces at different points. This is why you are so confused. If F1 and F2 were always the same magnitude, but opposite directions, it would never move at all. When you push on something, it moves because the opposing force is from inertia, which is another way of saying "acceleration". That is an example of Newton's 3rd law. Pushing on an fixed object is another example, where you push on the object and it pushes right back. In all cases, the forces are on the same point, in opposite directions.
You think F1 and F2 are related, being the same magnitude and opposite direction because of some mysterious natural phenomenon transmitting the forces to one another. This is not Newton's law. It's also not true. Newton's law says the treadmill pushes on the wheel and the wheel pushes back on the treadmill. F1 and F2 are coupled through the mechanical leverage of the pulleys, etc.
--- End quote ---
You are used with vehicle that have an obvious power source usually a motor or engine connected between the vehicle body and wheels.
This is about a special case and I will get why you are confused.
The body of this vehicle is isolated not in contact with the ground or the thing that powers the vehicle.
This vehicle has only two points of contact and no onboard energy source.
When treadmill applies a force F1 on the vehicle the only the only way the vehicle can push back is through the other point of contact with F2 that will be opposite and equal.
This is not a powered vehicle is a pushed vehicle from outside by the treadmill and normally it will move in the direction is being pushed but due to the way the wheels are connected by the belt it is locked so if wheel on treadmill was to slip with no energy storage the vehicle will just stay in place while treadmill will waste energy due to friction with the wheel but since there is also the internal energy storage (belt elasticity in this case) the vehicle can store the energy and move forward a little bit using the small amount if stored energy then things will repeat.
What do you think happens if you weld the wheel to the vehicle body (so they can no longer rotate)? Is in that case Newton's 3'rd law applicable and F1=F2 ?
Because the way that belt is connected between the wheels is about the same thing in this particular case.
Or maybe think about this vehicle with the belt removed.
If there is zero friction the wheel on the treadmill will just spin at the same speed as treadmill while the back wheel is stationary same as the vehicle body.
If you add a brake at the wheel on the right or an electric generator then vehicle will move from right to left so you will be able to produce only a limited amount of energy ideal case equivalent with vehicle potential energy based on treadmill speed and vehicle mass
Once the vehicle speed equal treadmill speed you can no longer produce any energy.
If you take that energy and apply to the wheel on the red box that will just be enough ideal case to bring the vehicle back to a stop.
This is a complicated way of saying that Pout can not be higher than Pin.
gnuarm:
--- Quote from: electrodacus on July 20, 2022, 11:17:58 pm ---
--- Quote from: Naej on July 20, 2022, 11:10:56 pm ---
--- Quote from: electrodacus on July 20, 2022, 10:55:48 pm ---Newton 3'rd law applies to F1 and F2 the same way it applies to F3 and F4
--- End quote ---
Sure, but what does it say?
--- End quote ---
What do you mean but what does it say?
If the red box was perfectly slippery then F1 will be zero (that is after mass of the vehicle was accelerated from right to left).
Even will far less than perfect slip on the left wheel (just needs to slip before the right wheel has the chance to do that) the vehicle will just slide from right to left as I demonstrated here https://odysee.com/@dacustemp:8/stick-slip-removed-from-front-wheels:0
--- End quote ---
This video shows the car working exactly as I described it. In the beginning, you are doing something that makes the car move with the paper without the wheels turning. But once you reposition the car, it moves opposite to the motion of the paper (the treadmill) which is exactly what I said it would do.
How can you be in denial of your own evidence??? The fact that your wheels are not very sticky and slip a lot, doesn't mean it's not working. The slipping is what screws it up. When the wheels don't slip, the car moves opposite the paper. The wheels are turning and not slipping, proving your idea of the wheels being "gearbox locked" is pure bunkum.
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