Why don't magnetic motors work?

AI Thread Summary
Magnetic motors cannot work due to fundamental physical laws, primarily the conservation of energy. The discussion highlights two key issues: the difficulty in achieving a net torque from magnet configurations and the inevitable energy loss from induced currents that generate heat, leading to demagnetization. Even if a configuration could produce torque, the system would still not be sustainable due to these energy losses. The consensus is that without an external energy source, a magnetic motor cannot function, reinforcing the principle that free energy is unattainable. Ultimately, the concept of magnetic motors is flawed and unviable.
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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