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So I had this thought of a spinning disk that would spin forever in space then I imagined that on this disk there were magnets of alternating poles on the disk and then I imagined a bunch of copper wire round up in loops to capture and create electricity. What I’m saying is can an idea such as this be taken seriously.

Personally I already worked the mechanism out with realistic ways to make a friction less set up using magnetic bearings and diodes and transformers.

The main reason I’m asking is because an idea like this would get easily scoffed at. So you pitching in would help a lot.

Qmechanic
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no name the astronaut
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  • Perhaps, over time, your permanent magnet will lose its magnetic properties. – Kshitij Kumar Oct 12 '21 at 03:46
  • i would prefer it that way. – no name the astronaut Oct 12 '21 at 03:54
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    Mechanical friction is not the problem here. Your electricity generator will be taking energy away from the spinning object, causing it to spin down. That's just conservation of energy. The mechanism by which this happens is unavoidable: it's just electromagnetic induction. The very process of creating currents will cause the rotation speed of the spinning object to decreases. – march Oct 12 '21 at 03:58
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    Admittedly I couldn't find a duplicate target that combined magnets, diodes, and being in space, but questions like this have been asked many times. – Chris Oct 12 '21 at 04:19
  • Related: https://physics.stackexchange.com/q/75471/2451 – Qmechanic Oct 12 '21 at 06:14
  • You don't need to be in space. Same thing on Earth as in the Heavens: it will stop when the kinetic energy is converted into electric energy. – nasu Oct 12 '21 at 11:37
  • Could you explain what you meant when you said spin down. I agree with what you said its just that this confused me. – no name the astronaut Oct 12 '21 at 12:34
  • I don't think induction would be that much of an issue (this guys videos shows how i would use the disk of course without the base https://www.youtube.com/watch?v=yhu3s1ut3wM&t=535s)but what it does show is that eventually the disk will stop moving and this is not good at all i wish i could show you the drawing of it but i can't sadly so im left to explain it in words. Remember when i mentioned the transformers and diodes well this was for a way to feed the energy back into the system. thx for being patient – no name the astronaut Oct 12 '21 at 12:46
  • The idea was to use the diodes to convert ac to dc so i could use it to make an electromagnet. And the transformers was so you could transmit the power to the set up without touching. A second wheel connected the the same shaft as the first wheel whit the magnets set up in such a way as they would be constanty pushed.

    the main thing is to put more energy back in to the system then that witch is lost. Primarily through induction.

     – no name the astronaut Oct 12 '21 at 13:18
  • This may be helpful to understanding the answer to your question. Start a portable gas powered generator and then put a load on it, maybe a saw or heater. You will hear the motor labor, so even if you were able to despense with the friction, the load would still be there. – Lambda Oct 12 '21 at 15:58
  • You would still lose energy through heat. – Abhinav Oct 12 '21 at 03:47
  • @Lambda I agree, But the focus that i'm trying to bring into light here is will the load be enough to stop such a contraption. This is something that i battle with myself about. So far no one will give a sliver of knowledge to me about it. – no name the astronaut Oct 12 '21 at 16:13

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This will not work. As the magnets induce a current in the wires that current will produce a force on the disk, slowing it down. Even neglecting losses, it will only produce as much electrical energy as there was in the original kinetic energy of the disk. It is not a perpetual energy device, but a flywheel energy storage device.

Dale
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  • so i took what you said to heart but i have one last question for you relating to this set up. Wouldn't it be possible to attach a motor at the bottom of the device to ensure that the potential electric energy will keep spinning by adding some of the electricity back in the system? – no name the astronaut Dec 02 '21 at 12:19
  • Assuming no losses anywhere (a non realistic assumption) then yes, you can use a generator to convert KE to electrical energy. Then use the electrical energy to run a motor to restore the KE that the generator took. No net gain is possible, but if there were no losses (not realistic) then you could break even – Dale Dec 02 '21 at 12:32
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Unfortunately for humanity, there is no way to get work out of a perpetual motion machine without dropping the "perpetual". The short answer is that the amount of energy in a closed system is conserved.

Let's look at your system: it takes energy to increase the current in a copper wire. There are two sources of energy in your machine: the energy stored in the magnetic field and the energy of rotation. If the current increases, then, counterintuitive as it seems, the energy has to come from one of those places.

Energy conservation is often useful in physics because it allows one to determine behavior of a system without having to get into messy details. However, you may be interested in these messy details — how, exactly, does the strength of a magnetic field or the angular speed of a rotating body become current? You might check out "eddy currents". This demonstration shows how the motion of a conductive body can be converted into current within that body.

fibonaccho
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  • I mean yeah but this doesn't stop conventional generators all that much. And the rate at which the induction would slow it down wouldn't affect it all that much. I know this because of this video it also features similar idea except he dosent try to feed the energy back into the system.https://www.youtube.com/watch?v=yhu3s1ut3wM&t=544s – no name the astronaut Oct 13 '21 at 00:52