Choose parameters for a system

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The discussion centers on the theoretical study of two disks rotating at the same speed and the feasibility of selecting parameters such as density, radius, and position of materials to achieve desired forces in the system. It is noted that achieving the drawn results is complex, with no straightforward parameter choices available. The concept of buoyancy and weight contributing to a net tangential force is challenged, emphasizing that centrifugal gravity operates differently than assumed. The idea of perpetual motion is also dismissed, indicating that the proposed setup cannot function as intended. Ultimately, understanding the forces involved and ensuring proper conditions for rotation and pressure variation is crucial for any practical application.
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Theoretical study. Disks are one above the other. Turn at same rotationnal speed w.

Is it possible to choose good parameters for:

- density
- radius
- rotationnal speed
- position of d3/gas: d3 in disk1 at radius R1, d3 in disk2 at radius R2, gas in disk1 at radius R2, gas in disk2 at radius R1
- size of disk

For have forces like I drawn on the system ?

NB: disk must be big enouh for have gravity effect (1000 km for example). Center of rotation is supposed fixed.
 

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No - there are no easy choices of parameter that will produce the results you have drawn.
BTW: the green one is nonsense.

Looking at the blue one:
I can see what you are doing - you think the buoyancy and weight will add to a net tangential force.
Centrifugal gravity does not work like you seem to be thinking.

You realize this is perpetual motion?
Therefore it does not work...

Some notes:
It does not matter how big the disks are - all you need is enough rotation to get the pressure of the liquid to vary with the radius so it is highest at the rim... and you want the blue liquid to be light enough to have zero drag effect.

Make sure you have included all the forces.
 
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Since the time I posted the thread I understood. thanks for your help.
 

Thread 'Reference frames, center of rotation, etc'

Topic about reference frames, center of rotation, postion of origin etc Comoving ref. frame is frame that is attached to moving object, does that mean, in that frame translation and rotation of object is zero, because origin and axes(x,y,z) are fixed to object? Is it same if you place origin of frame at object center of mass or at object tail? What type of comoving frame exist? What is lab frame? If we talk about center of rotation do we always need to specified from what frame we observe?
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