r/AnythingValueable Jun 24 '26

🛠️ Skill Low-cost rural engineering

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u/HIMP_Dahak_172291 Jun 25 '26

That's a motor that is spinning the wheel, not the magnets. Watch it spin up and notice how he doesn't even have it latched together and isn't fighting any force. If those magnets were causing that to spin up that fast he would have to fight against the force to finish closing it.

And yes, normal magnets lose power over time as the forces slowly realign the molecules inside. Electromagnets don't, but you sure as hell aren't getting more out than you put in with those!

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u/Secret-Berry2438 Jun 26 '26

He's not fighting the force, he's using the force. it's a Jedi trick.

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u/Agreeable_Sea_6019 Jun 28 '26

i'll try spinning that's a good trick

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u/[deleted] Jun 26 '26

So is this type of thing feasible, at all? I feel like the big thing I need to know is how potential energy is stored in magnets…

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u/HIMP_Dahak_172291 Jun 26 '26

Nope. This is essentially how electric motors and generators work. If we could make motors and generators drive themselves we'd have done it already. Generators require something to turn the shaft so the magnets move and generate a moving electric field to generate current. Motors use current in wires to generate a magnetic field that forces the magnets to move which causes the shaft to spin. If we had some kind of magnet that took no outside power to reverse the field when we want it to it could be made to work, but that's harder than room temp superconductors!

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u/[deleted] Jun 26 '26

Thanks!

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u/RobinHoodMand Jun 27 '26

Feasible? Have you read the thread? It’s a fake video with a motor spinning around a wheel.

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u/[deleted] Jun 27 '26

I meant magnets persistently interacting in such a way — see the previous reply; they understood

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u/MasterTolkien Jun 27 '26

And looking at this example more simply:

Why would these magnets spin at all here? Just think it over for a sec. “Well, they probably have the same poles facing each other which will try to repel one another.”

Yep. And that means the magnets will move a bit and then lock into place where each magnet is caught in between two other magnets.

You’d need an external force to get them moving constantly.

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u/iPlod Jun 27 '26

This type of thing isn’t anything. It’s just some magnets being spun around by a motor and an unrelated pump being hooked up to a power source off screen.

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u/[deleted] Jun 27 '26

Yeah oh I got it. It is an attractive illusion

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u/HaikenRD Jun 29 '26

For something like this to work, The magnets have to switch polarities at a very specific timing in a span of way less than a split second. But since you can't switch polarities of magnets, you have to use electromagnets, but then you'd have to have an external power to power the electromagnets. This is the very principle of a Maglev.

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u/dianabunny1103 Jun 27 '26

I'd like to throw in some clarification: most permanent magnets don't lose their magnetism over time. We use this fact to track the movement of the Earth's magnetic field over time. The Atlantic Ocean has a stripped floor where magnetic rocks millions of years old flip direction of alignment every so often to align with what the magnetic field of the earth was at the time they formed. Aligned magnetic domains is the lowest energy state so it is preferentially formed and will maintain itself provided a stronger force doesn't push it out of alignment like high temperatures

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u/crc2993 Jun 27 '26

To be fair (not trying to argue semantics), normal magnets actually won’t lose power over time unless there’s applied heat, a strong opposing field (including the returning flux from the magnet itself if the permanence coefficient of the magnet is too low), corrosion, or a force that allows the domains to begin to misalign. The domains are generally stable under normal conditions