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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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2 Answers2

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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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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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