Physics Q

[gumpzilla]

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They are symmetric as far as I am aware, if I take one away, the other one falls down (obviously?), they are these things if that helps any.

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Spin them on a flat surface parallel to the ground and see if they possess the same dynamics.

[kerowo]

You've got gravity pulling them down, you've got the friction on the glass surface, you've got the magnetic force attracting them, and then there is whatever force you apply to the magnet. FTW.

[jkkkk]

I really have no idea what this means, they are both exactly the same, if I spin them on a flat surface they both spin freely unless there is any magnetic attraction close in which case they both react in the same way by pausing and slowing down at certain points.

[jkkkk]

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You've got gravity pulling them down, you've got the friction on the glass surface

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Heading in the right direction.

[gumpzilla]

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I really have no idea what this means, they are both exactly the same, if I spin them on a flat surface they both spin freely unless there is any magnetic attraction close in which case they both react in the same way by pausing and slowing down at certain points.

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Okay, is this slowing down and speeding up periodic? What's the period of the motion?

I've sort of been assuming the magnetism really isn't the issue. Since these things are parallel at all times, I think the force of attraction between them should be constant. If any weirdo EM effects are going on, I'm wondering whether your spinning magnetic dipoles are storing some linear momentum in the EM fields, and then conservation of momentum might lead to what you see. But if this were the case I would have thought that one of these puppies alone would probably do the trick.

[jkkkk]

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I really have no idea what this means, they are both exactly the same, if I spin them on a flat surface they both spin freely unless there is any magnetic attraction close in which case they both react in the same way by pausing and slowing down at certain points.

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Okay, is this slowing down and speeding up periodic? What's the period of the motion?

I've sort of been assuming the magnetism really isn't the issue. Since these things are parallel at all times, I think the force of attraction between them should be constant. If any weirdo EM effects are going on, I'm wondering whether your spinning magnetic dipoles are storing some linear momentum in the EM fields, and then conservation of momentum might lead to what you see. But if this were the case I would have thought that one of these puppies alone would probably do the trick.

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I think you are overthinking this and that

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Since these things are parallel at all times, I think the force of attraction between them should be constant.

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Is true.

[MediaPA]

Ok, I'll be slightly more serious. If they are perfectly in sync (which wouldn't be the case).

Gravity - Remove gravity (ie - turn panel horizontally), magnetic forces balance out, no different then spinning a bar of iron. With no other forces, the bar will just spin in place.

Remove Air Resistance (vacuum) - I propose that the system would fall straight to the ground (regardless of which diretion you spin it).

Therefore the forces that move it to one direction over the other have to do with the spin of the object and air resistance due to downward movement caused by gravity. I can't describe this at the moment because I haven't tried to think in 5 years or so.

[gumpzilla]

It's possible I am overthinking this but I don't see what breaks the symmetry and causes motion to the right or left if it isn't any of the things I've said before. It's clear that the symmetry is broken, it's just identifying the cause that's puzzling me.

Here's one thing that may have something to do with it: because it's falling AND spinning, the speed with which it moves will be different on the two sides (if it's spinning clockwise, the left hand side has a slower velocity measured relative to the ground.) So if your friction is velocity-dependent (good for air resistance type [censored] but not a super standard model for friction between surfaces, I don't think) then I could see something like this happening.

[jkkkk]

Its confusing, took me a week to figure out, well.. I'm 95% sure I'm right, I don't think it has anything to do with air resistance.

I'll post this is SMP as well I think.

[DrVanNostrin]

I'll take a stab:

1 )The changing magnetic field induces an electric field.
2) The changing electric field then induces a magnetic field.
3) The magnets feel a force.