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/sci/ - Science & Math

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10985807 No.10985807 [Reply] [Original]

>Blue flywheels rotate in the opposite direction of the green flywheels. The black axle itself is not spinning, but its mass is far less than the flywheels. The device is floating in outer space and under its own power.

This isn't one of those retarded puzzles or anything. Does anyone know which of these two is more stable, if they have different levels of stability? I know that there's a huge issue with longer objects rotating due to the tennis racket theorem. Regardless of how stable you want a spinning object to be there's always going to be at least 3 difference angular forces playing upon it.

>> No.10985840
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10985840

>>10985807
How do you mean stable? Setup B will tend to precess if one tries to rotate it in the plane parallel to the screen. I don't call that stable. Setup A has the advantage of having no new angular momentum.
Tennis racket theorem doesn't apply here. TRT is just a statement about principle moments of inertia, for which they are identical for each setup.

>> No.10986029

>>10985840
Fuck off furry, you have no clue what you are talking about in any regard.

>> No.10986773

>>10986029
hes right tho

>> No.10986782

>>10986773
>How do you mean stable?
Oh with that type of start? lol No.

>> No.10986796

>>10986029
Feel free to enlighten me, fag.

>> No.10987911

I too am interested in the OPs question.

>> No.10988041

>>10985840
>>10986796
>>10987911
It seems pretty simple, in regard to what is wanted. "Stability," would mean that its main angle of force isn't being moved around by other angular forces. The TRT applies since the device is in space and isn't attached to a larger object like on Earth or similar non-moving base structure. Despite that, TRT applies to anything spinning really, it is just that it is negated by being attached to something else. This is because, in reality, you can't negate all forces of angular momentum due to everything else in existence affecting it (gravity from planetary bodies, solar wind, GCR, starting point inertia, etc.) Obviously, which of the two devices in the OP would flip, flip first, or flip at higher frequency?

If A only had two flywheels spinning then it'd more than likely start flipping quickly and often. Since it has multiple and they are rotating opposingly every other flywheel then it will be far more stable. Though, it may still start to flip.

B on the other hand has everything spinning one direction, expect the black axle, which must be spinning in the opposite direction. I assume the mass of all the flywheels is more than the mass of the axle. Thus, I believe that B would start flipping before A and would do so at a higher frequency.

>> No.10988859

>>10988041
Thanks for explaining. Does a single rotating ring avoid any chance of flipping or must it function as a gyroscope, consisting of two rotating rings at right angles?