Why don't magnetic motors work?

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SUMMARY

Magnetic motors, which rely solely on the repulsion of magnets to generate work, are fundamentally flawed due to two primary reasons. First, achieving a configuration that produces a net torque is highly challenging, if not impossible. Second, even if such a configuration were found, the induced currents from the spinning magnets would generate heat, leading to demagnetization and a subsequent decrease in performance. Therefore, the consensus is that magnetic motors cannot function as a perpetual energy source.

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  • Understanding of magnetic fields and forces
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dipole
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THIS IS NOT A POST ABOUT FREE ENERGY. I know this topic is against the rules, and I am not foolish enough to believe such a thing exists.

I just want to understand the root flaw in such a concept. I have two suspicions about why you can't use the repulsion of magnets (with no other source of input) to generate work.

The first is that its difficult (maybe impossible?) to find some configuration in which any net torque is actually produced. The second is that even if you could find some configuration in which a net torque is produced, the spinning of this wheel of magnets is going to induce currents, which generate heat, and act to demagnetize the magnets, causing your wheel to inevitably slow down.

How far off am I?
 
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dipole said:
THIS IS NOT A POST ABOUT FREE ENERGY.

Yes it is. There is no free energy, so there is no way such a motor can work, regardless of the design. There is no need to discuss anything beyond this point.
 

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