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 What's wrong with that device (potential energy) ?
Сообщение03.12.2016, 01:01 
I imagined that device:

Blue color is small spheres like the size of molecules of water. No mass (very low in reality). No friction (very low in reality). I attract them from the green line the blue spheres. The area is constant. The green line is fixed to the ground. Each spring has an end attached to the green line. Each small sphere is attracted by a spring. If there are 1000 springs, there are 1000 blue spheres. The white disk rotates around the pink dot. The pink dot is fixed to the ground. The orientation of the springs follows the slope of the walls. The law of attraction can be linear or not. I noted some pressures 'p'.

The cycle:

Изображение

I zoom in some parts:

Изображение

How I move in/out the spheres in the same time I rotate the white disk:

Изображение

I can resume the logic:

Without the white disk:

At start, I have the potential energy X
Rotate the walls give me the energy W
At final, I have the potential energy , with $Y<X$ and X is equal to $W+Y$

With the white disk and without move in/out the blue spheres:

At start, I have the potential energy X-d, with d the potential energy lost because there is the white disk (where the white disk is there is no springs)
Rotate the walls give me the energy W
At final, I have the potential energy , with Y-d and $X-d$ is equal to $W+Y-d$

The energy is well constant in the last 2 cases

Now, I move in/out the blue spheres from the container because the white disk rotates inside the container, it is the same case than before, except that I win the length from the springs I move out/in. Like the length of the springs pass from L1 to L2 I win a potential energy but I don't lost any other energy ?

 
 
 
 Re: What's wrong with that device (potential energy) ?
Сообщение09.12.2016, 18:15 
Hi,

I thought with a fixed white disk and like that the sum of energy is constant. So, this would say the pressure don't change because the spheres move in/out. And it is logical because like there is no mass and no friction the delay to have the pressure is 0. The pressure comes from the spheres above. If the pressure don't change because I move in/out the spheres, the only way to lost an energy comes from the in/out but the pressure is the same...

Someone has an idea where the energy I recover from the difference of lengths of the springs come from ?

Maybe nobody understood what I wrote ?

 
 
 
 Re: What's wrong with that device (potential energy) ?
Сообщение11.12.2016, 20:55 
I don't wrote but I suppose the force of each spring the same and the force is constant even the length of the spring changes like that it is easier to study.

 
 
 
 Re: What's wrong with that device (potential energy) ?
Сообщение13.12.2016, 23:55 
I drew a big thickness but it is possible to study the thickness with one layer of blue spheres. Even with one layer of blue sphere the sum of energy must be constant.

Why the pressures couldn't be like I think ?

 
 
 
 Re: What's wrong with that device (potential energy) ?
Сообщение14.12.2016, 07:42 
Аватара пользователя
 !  dxtx, the prevention for you, because of repeated lift of the topic by the empty messages.

 
 
 
 Re: What's wrong with that device (potential energy) ?
Сообщение08.03.2017, 20:28 
I think with that new device:

Изображение

To look where I was wrong in my last device. In that new device, I found well the sum of the energy at 0 with the same method I used for the last device. The blue volume is constant. No mass (very low in reality) and no friction (very low in reality).

So, the method must be correct. Have you any idea where I'm wrong in my last device ?

I gone to Moscow and Perm to visit the cities, and very few people in Russia speak english, so maybe it is for that nobody reply.

 
 
 
 Re: What's wrong with that device (potential energy) ?
Сообщение08.03.2017, 20:35 
Аватара пользователя
Or maybe that's because your problem is boring and not well-posed.

 
 
 
 Re: What's wrong with that device (potential energy) ?
Сообщение08.03.2017, 21:06 
Boring, maybe the device like I explained. But I took a lot of simplifications: no mass, no friction, blue volume constant to simplify the equations. I don't know what to add to explain better the device because I don't know what people don't understand.

 
 
 
 Re: What's wrong with that device (potential energy) ?
Сообщение08.03.2017, 21:55 
Аватара пользователя
What's the goal of the device?

 
 
 
 Re: What's wrong with that device (potential energy) ?
Сообщение08.03.2017, 23:04 
Increase the potential energy of a device more than I supply.

 
 
 
 Re: What's wrong with that device (potential energy) ?
Сообщение08.03.2017, 23:16 
Аватара пользователя
Have you heard of the law of conservation of energy?

 
 
 
 Re: What's wrong with that device (potential energy) ?
Сообщение08.03.2017, 23:37 
Yes, I know, but I don't find the error in that device.

 
 
 
 Re: What's wrong with that device (potential energy) ?
Сообщение09.03.2017, 00:17 
Аватара пользователя
dxtx
The purpose of you device is to gain an energy from nowhere. Not only it's against law(s) of physics but also very old. On top of that, the description of the device is utterly vague and hard to understand.
I am not a physicist, nevertheless I don't think there are many people, who would be interested in helping with this.

 
 
 
 Re: What's wrong with that device (potential energy) ?
Сообщение09.03.2017, 09:16 
Цитата:
The purpose of you device is to gain an energy from nowhere.
But I know there is an error.

Цитата:
the description of the device is utterly vague
The device is not so complex than that. I studied the sum of energies from the start position to the final position. At start, there is a stored energy (potential energy) from the springs. The left and right walls gives an energy recovered by a device (not drew). At final, there is a stored energy from the springs. The force of attraction of the springs follows the angle of the left (or right) wall. I studied the device without a white disk, the energy is conserved: X=Y+W, X is the stored energy at start, Y the stored energy at final, W the energy from the walls. I add a white disk, now I lost a little stored energy 'd' at start because there is the white disk (where there is the white disk I can't put blue spheres, so there is fewer springs) but I lost the same at final because the white disk rotates, the equation becomes: X-d=Y-d+W. If it was all the energies, the sum is conserved. But, when the white disk rotates, I move out the container the blue spheres in front of the white disk and I place them behind the white disk. The volume is always constant, exactly constant, so I need only one layer of blue spheres because I can't move out the same layer I move in. There is a difference of length L1 vs L2 for the springs. I win the potential energy from the difference of lengths, I called that energy 'e'. The equation is X-d=Y-d+W+e.

 
 
 
 Re: What's wrong with that device (potential energy) ?
Сообщение09.03.2017, 11:40 
dxtx в сообщении #1198210 писал(а):
Boring, maybe the device like I explained. But I took a lot of simplifications: no mass, no friction, blue volume constant to simplify the equations. I don't know what to add to explain better the device because I don't know what people don't understand.


Try to extract from this device smallest possible element, where work of external forces is not equal to energy change. Current descrition is just puzzle "find cat on this big picture"

 
 
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