Perpetual motion

[arkain101]

Originally Posted by Uncle Martin

I know this seems a bit silly, but I've got an idea using magnets that seems feasible, at least in my mind. I just haven't had time to try it. Is it truly impossible, or simply not yet done? Does perpetual motion break any laws of physics, or is it only not proven possible mathematically?

Note: I will move this to Inventions and gadgets when Tormod gets a reply to his guitar rig question. I didn't want to bump that down the list.

I am probably repeating a bunch of stuff that has already been said. Anyway, magnets can be arranged in some interesting ways. I've seen a few devices spin for a suprising amount of time. However, I think the moment you put a load on the device it spirals down and quits even sooner. However, this is not to say one can not arrange magnets to produce a useful engine. (with very little input, in order to get massive output)



One way I look at perpetual motion is this. Take a wheel, and spin it very quickly and put it in orbit around the earth. The wheel will spin for a very long time, but that is only because it isnt doing any work. If we tried to use the wheel for energy, the wheel would slow down as we essently suck energy out of it.

So even if perpetual motion relatively exists, when you put it to use, it stops.

[arkain101]

However, this is not to say one can not arrange magnets to produce a useful engine. (with very little input, in order to get massive output)

Like this basic idea. In this setup, you have repulsive magnets placed (with a fixed diameter) on the outside of an oval wheel. After the high point has been reached the magnets repelling with the wheel, cause the wheel to spin.

The magnets can move perpendicular to the rotation of the wheel, so after they accelerate the wheel, they are moved out of the way so that the wheel can spin, and the magnets won't repell the wheel on the next 1/2 of the rotation, Suppose the wheel spins 10 times, Then the magnets are placed back into position at a key moment to accelerate the wheel again.

The only energy being spent is the motion of the magnets, which could be backed by springs so that the energy used to change their direction is minimized.

You can imagine just using your finger and thumb to gently wiggle the 2 magnets back and forth (perpendicular to direction the wheel is spinning) with the right timing to spin the wheel. (taking in the fact the two magnets are connected to a single frame that can pivot on an centered axle, if you follow?)


Or you could suppose that the wheel itself had a curved track line, S shaped head on profile, and the magnets were stationary. With a precise curvature, that enables the magnets to provide thrust in only one direction. This should remove the need for any moving parts (if I picture this in my mind correctly it would spin)


The output could be greater than the input, but it would likely require a second system to do so.


This idea of manipulating engine configuration can be used many places.

In cars for example, it would be more efficient to build small lightweight internal combustion engine that turns a generator at a constant rpm, which in turn powers the electric car, than it is to have a combustion engine configured to run at all kinds of different rpms while connected to a transmission and drive line.

When we try to build a car engine to operate at various rpms and loads it becomes incredibly complex to maintain efficiency. Where as, if you took a diesel engine and configured it to run with its best power to efficiency range around 1000rpm, and connected it to a generator, the engine would use very little fuel, while producing constant charge and power, which could be delivered through electric engines much more efficiently than a transmission / differential drive line.
(I have no proof of this, I am simply speculating based on general knowledge)

[arkain101]

Then again, there is always that initial force that gets in the way when the magnets attempt to pass over each other.

[TEguy]

Like poles repel, opposite poles attract.
...or was it the other way around...

[lawcat]

Perpetual Motion is a particle, earth, Sun, for all practical purposes. If it exist, then it can be created. Any discovery, and there have been some in the past, that is or approaches perpetual motion will be rejected because it is not economical; it does not result in economic dependency.

[freeztar]

Originally Posted by lawcat

Perpetual Motion is a particle, earth, Sun, for all practical purposes.

This is not true. Stars burn out, planets disappear, and particles are theorized to lose all of their energy somewhere down the line (+ years away at least) if the universe keeps expanding.

If it exist, then it can be created.

You sure about that? I exist, though I've never seen anyone create another me. Not that it is eternally impossible, but it currently is.

Any discovery, and there have been some in the past, that is or approaches perpetual motion will be rejected because it is not economical; it does not result in economic dependency.

I agree that it is not economical in an energy sense. You're always losing more than you spend. No investor would bet on that.

[UncleAl]

1) Time is locally homogeneous.
2) Noether's theorems.
3) Mass-energy is locally conserved.

There are two ways out:

1) alter the local flow of time, or
2) overthrow the whole of mathematics.

Go for it.

[Sir Isaac Einstein]

If people would only think of gravity as a force, that can be 'milked' ----- the problems would be
solved.
If one continualy believes the so-called 'law - makers' as being correct all of the time, and they are
eventualy proved wrong ----- so be it! If the so - called 'laws' governing perpetual motion saying, it's
impossible ----- so be it!
Sir Isaac Einstein

[Moontanman]

No SIE perpetual motion is not thought to be impossible it is impossible. I suggest you try to build a few perpetual motion devices and see.

[Pyrotex]

Originally Posted by Uncle Martin

A magnet and gravity can both perform a work function without any introduction of, or loss of any energy. Would you consider this an accurate statement?

Over a finite distance, yes.
Gravity and magnetism do indeed pull on stuff without having to supply energy.
But gravity and magnetism "perform a work function" only by converting a potential energy into kinetic energy -- over a finite distance.

For either of those forces to work indefinately, you would need either:
the original potential energy to be infinite, or,
the working distance to be infinite.
Neither one is gonna happen.