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AndrewGPaul
2005-Sep-11, 09:51 AM
So, a friend of mine sent me this image:

and for the life of me, I can't see the problem. My first thought was that the magnets accelerating thw ball upward on the return of the loop have to get that energy from somewhere; would they demagnetize eventually? or, would they need to be sufficiently strong that they'd fix the ball bearing in place rather than accelerating it?

Van Rijn
2005-Sep-11, 10:01 AM
I'm sure he never built this. How do you get statically placed permanent magnets to accelerate a ball bearing? The best you can hope for is that they won't slow the ball bearing down much.

Short answer: Unless you put in energy, the ball isn't going around for long.

Fortis
2005-Sep-11, 11:50 AM
Two problems with the device. The first, as Van Rijn has pointed out is that the magnets would not only attract on the way up, but would also attract (i.e. retard) after the ball bearing goes past, i.e there is no net gain.

The second problem is that the magnets will also induce eddy currents in the ball-bearing which will dissipate the original energy of the ball bearing quicker than if the magnets weren't there in the first place.

papageno
2005-Sep-11, 12:42 PM
The second problem is that the magnets will also induce eddy currents in the ball-bearing which will dissipate the original energy of the ball bearing quicker than if the magnets weren't there in the first place.
Also, if the ball is ferromagnetic, you have hysteresis which dissipates energy and heats the ball.
And still he has to show how he would extract the "excess" energy to do useful work.

AndrewGPaul
2005-Sep-11, 02:53 PM
Well, there is an impeller marked on the diagram (green cross), that would presumably power a dynamo or something.

Basically, I was thinking the same thing; the magnets would basically hold the ball in place, rather than accelerate it. I assume that even if the ball has sufficient inertia to pass round the loop a few times, that eventually friction losses (and the distorting and heating effects of the magnets on the ball) would slow it sufficientlyto allow it to be captured. I take it that you're also saying that the ball will be decelerated after it passes the magnets just in the same way it's accelerated as it comes towards them?

Van Rijn
2005-Sep-11, 09:37 PM
I take it that you're also saying that the ball will be decelerated after it passes the magnets just in the same way it's accelerated as it comes towards them?

Yes, and more than that. A static magnetic field isn't going to supply a moving ball with excess energy, but it will take some. You either need to move the permanent magnets, or use a powered rail or coil scheme - something that isn't static. And, of course, that takes energy. You will have to put more energy into the system then you will get out.

There is a long history of magnets in perpetual motion machine schemes, this isn't new at all.

blueshift
2005-Sep-12, 04:51 AM
It doesn't matter how powerful the magnets are. The circular motion is an accelerating motion that loses energy. Ball bearings in an auto that is continuously being fueled while it is in motion will eventually wear out...Nice try..no cigar. In fact the U.S. Patent office has issued a statement that it will not recognize any perpetual motion machine because if it did, it would violate time symmetry.

Time symmetry points to the fact that the laws of physics do not change with time. If you have succeeded in inventing a perpetual motion machine then you will have succeeded in proving that the laws of physics do change with time and, in that case, I will not buy your machine because the laws of physics can change again and it will not work in the future, negating its warranty and negating the existence of all warranties.

j0seph
2005-Sep-15, 09:26 PM
I don't think that propetual motion devices are possible, but saying that the laws of physics change because you 'proved' them wrong is ridiculus, and to me is a pitiful excuse for not accepting the devices, because who knows, there might be a way to create one that we cannot comprehend with our current mental capacity; but I do see why they are using this excuse, they just need a better one :)

peter eldergill
2005-Sep-16, 01:53 AM
My understanding is that a true superconductor will offer zero resistance to a current and that you can have a current flowing through a loop of the superconductor indefinaletly

I recall something similar about some supercooled liquid helium offering zero friction (or something like that)

Could these be considered perpetual motion, or are you referring to " more energy output than input" kind of thing?

Pete

Enzp
2005-Sep-16, 04:01 AM
Well, to get your superconductors into their superconducting state you have to keep them super cool, and that takes energy. Even a current that would go on forever under those conditions will diminish if it has to do some work, so you could not take any "free" energy from the system.

blueshift
2005-Sep-19, 03:14 PM
I don't think that propetual motion devices are possible, but saying that the laws of physics change because you 'proved' them wrong is ridiculus, and to me is a pitiful excuse for not accepting the devices, because who knows, there might be a way to create one that we cannot comprehend with our current mental capacity; but I do see why they are using this excuse, they just need a better one :)You don't understand something..That isn't an opinion. That is almost directly from a statement placed out by the patent office. If the laws of physics change with time, then the laws that made the perpetual motion machine will also change with time and the machine will not function in the future..

It is often a misnomer perceived by the inexperienced that science grows out of infinite creativity that is perceived to exist within human consciousness. It didn't. It grew to its present stage out of limits that were recognized and measured.

You cannot make a gain in life. You can only make exchanges. The law of conservation holds a lien on that.

Swift
2005-Sep-19, 05:50 PM
Well, to get your superconductors into their superconducting state you have to keep them super cool, and that takes energy. Even a current that would go on forever under those conditions will diminish if it has to do some work, so you could not take any "free" energy from the system.
Even ignoring the energy to cool, they are not perpetual motion. You need to put energy in to start the current flow and if you take energy/work out the flow will eventually stop. I believe there has been talk of using such systems for low-loss energy storage (like a battery), but not energy generation.

zebo-the-fat
2005-Sep-20, 08:45 AM
In the end, whatever system you devise, you can't get more out than you put in!

In a power station you put energy into it in the form of coal, uranium whatever - then extract that energy to do useful work. When it's been extracted thats it, you need to add more coal etc.

You can't get something for nothing!

Moseley
2005-Sep-20, 12:00 PM
Saw a great interview with a bookmaker on TV - reckons the same man walks into his shop each year and bets £100 that he will invent a perpetual motion device. Our man went to local professor who assured him that 10,000 - 1 was still unreasonable so he keeps on taking the bets.

peter eldergill
2005-Sep-20, 04:27 PM
Even ignoring the energy to cool, they are not perpetual motion. You need to put energy in to start the current flow and if you take energy/work out the flow will eventually stop. I believe there has been talk of using such systems for low-loss energy storage (like a battery), but not energy generation. I think that's what I was referring to. I thought perpetual motion was the lack of friction, so a wheel would spin with no effort (once started). I never really expected to get energy out of it. just not lose energy

Pete

Taks
2005-Sep-20, 06:23 PM
but there is no such thing as a lack of friction...

taks

Taks
2005-Sep-20, 06:26 PM
i'm curious, btw, how the energy can be "infinite (albeit small)" all in one fell swoop? maybe he means "low energ, but lasting for an infinite amount of time"?

taks

hhEb09'1
2005-Sep-20, 07:09 PM
I think that's what I was referring to. I thought perpetual motion was the lack of friction, so a wheel would spin with no effort (once started). I never really expected to get energy out of it. just not lose energyPerpetual motion machines usually refer to the "'more energy output than input' kind of thing". The planets are fairly close to perpetual motion. For all human purposes maybe.

mnjose
2005-Sep-21, 10:39 PM
I am Joseph and a new member. I am working as a senior technical support engineer.
I bet, one day perpetual motion devices will work and will come into existence.
Although energy cannot be created or destroyed, it can be accelerated.

I have an idea for more than five years. The idea is inventing a Multi-purpose machine which works in pneumatic energy, which leads to generate electricity. No fuel or power is needed to run this machine except a small battery power is needed to start the starting motor. After a little time, the machine keeps on running and the initial battery power is cut off by automatic panel. I am aware that many perpetual motion devices failed several times. Many discouraged me too.

But I have 100% confident in my idea. One day I will make it work. The reason I couldn't make it prove now is due to finance. It may cost a little high to make a prototype. I know no one will give money or help for this. So I need to wait for a year or two to make money my own to prove this.

My website is: http://mnjose.co.nr
It would be an inspiring website. Just watch it.

Regards,
Joseph

Halcyon Dayz
2005-Sep-22, 02:57 AM
Well, good luck with it. :think:

Fram
2005-Sep-22, 08:02 AM
How can energy be accelerated? What is the speed of energy?

publiusr
2005-Sep-22, 04:26 PM
The closest thing I have seen to Perp Motion is the Barometer Clock described in the book Perpetual Motion.

Give it up.

Donnie B.
2005-Sep-22, 06:38 PM
A group (sorry, no cite available from this locale; maybe later if anyone's interested) has announced a MEMS design that produces a few hundred microwatts from mechanical vibrations. It could open the way to "batteryless" pacemakers that take energy from the patient's pulse, sensors that power themselves from the device being monitored, etc. It's built on silicon like an integrated circuit (requires a couple square millimeters IIRC).

It's not perpetual motion (any more than the barometric clock is), but it's pretty neat.

swansont
2005-Sep-22, 08:45 PM
I am Joseph and a new member. I am working as a senior technical support engineer.
I bet, one day perpetual motion devices will work and will come into existence.
Although energy cannot be created or destroyed, it can be accelerated.

I have an idea for more than five years. The idea is inventing a Multi-purpose machine which works in pneumatic energy, which leads to generate electricity. No fuel or power is needed to run this machine except a small battery power is needed to start the starting motor. After a little time, the machine keeps on running and the initial battery power is cut off by automatic panel. I am aware that many perpetual motion devices failed several times. Many discouraged me too.

But I have 100% confident in my idea. One day I will make it work. The reason I couldn't make it prove now is due to finance. It may cost a little high to make a prototype. I know no one will give money or help for this. So I need to wait for a year or two to make money my own to prove this.

My website is: http://mnjose.co.nr
It would be an inspiring website. Just watch it.

Regards,
Joseph

While your confidence is great, it's misplaced. Intellectual property offices are littered with folks who are convinced their perpetual motion ideas will work, and while the lawyers happily take their money, the devices are doomed to fail.

It's not a matter of engineering it just a little bit better. Energy is a conserved quantity, and corresponds to time symmetry by Noether's theorems. If energy is not conserved, it necessarily means that the laws of physics have changed. Add to that the fact that all engines must reject heat - i.e. there will always be losses - and your device can never run indefinitely on its own.

peter eldergill
2005-Sep-23, 01:11 AM
I remember an episode of the Simpsons when the school teachers were on strike (being a teacher myself, I found this episode hilarious!). Lisa and Bart needed structure in their lives and Marge was relaying this to Homer and the conversation went something like this:

Homer: "I know (they need boundries), this perpetual motion machine that Lisa built just keeps goes faster and faster)

Marge: "We've got to do something"

Homer "You're right! Lisa, get in here! (Lisa pokes her head)...As long as you're living in this house you'l obey the Laws of Thermondynamics!"

Hilarious stuff....purple monkey dishwasher

L8R

Pete

montebianco
2005-Sep-23, 01:37 AM
I know no one will give money or help for this. So I need to wait for a year or two to make money my own to prove this.

My first suggestion would be to save your money. But it is your money, you can do what you like with it...

publiusr
2005-Sep-23, 07:25 PM
A group (sorry, no cite available from this locale; maybe later if anyone's interested) has announced a MEMS design that produces a few hundred microwatts from mechanical vibrations. It could open the way to "batteryless" pacemakers that take energy from the patient's pulse, sensors that power themselves from the device being monitored, etc. It's built on silicon like an integrated circuit (requires a couple square millimeters IIRC).

It's not perpetual motion (any more than the barometric clock is), but it's pretty neat.

A very small device (a lot like Maxwells demon--basically a one way ratchet device) could be made to do just a bit of work from Brownian motion.

Ilya
2005-Sep-23, 11:43 PM
A very small device (a lot like Maxwells demon--basically a one way ratchet device) could be made to do just a bit of work from Brownian motion.
All ratchets depend on the slight flexibility of either the wheel itself, or of the "catch tooth" which prevents it from rotating backward, or of the frame that holds both. When the wheel moves forward a geartooth slides against the catch tooth, and the smoothly increasing force pushes the two apart. Once the geartooth slid past the catch, the out-pushing force is released, and the assembly compresses to its relaxed state. Without this elasticity the wheel would not move forward any more than backward. Materials strong enough yet flexible enough to make useful macroscopic ratchets are commonplace. On nano-scale, however, molecules are either rigid -- hold their shape with forces enormous proportionally to their size, -- or bend freely. Elastic compression simply does not happen to molecules without applying forces close to those needed to tear the molecule apart -- and for Brownian motion to do that, temperature must be so high that the molecules WOULD get torn up at rapid pace. Maxwell-Boltzmann distribution would see to that. Sorry, but a "Brownian ratchet" either won't work, or will work for a few microseconds before melting.

TrAI
2005-Sep-24, 01:57 AM
Hmmm... Even if someone does create a device that gives out more energy than is powering it, and all possible measuring errors have been eliminated, the device is still not likely at all to be more than 100% efficient, its more likely that they are just not plotting all energy sources into their calculations.

It's really no different than any other power generation, a power plant will use a little electrical energy from the grid, but then it can deliver a lot more back, but it does not mean the power plant is over unity, for calculations of efficiency in such things, all energy sources must be accounted for.

All these vacuum energy, cold fusion and what not generators one sees around the net is not likely to be over unity devices, even if they did work.

The only way one could have a true over unity device is if it created energy in some way as it was running(increasing the amount of energy in this space), and that is, as we all know, not an easy thing to do... Even importing energy from another space(I use space here to mean an entire space and time delimited from another, since the word universe kind of implies there is only one, and that all is inside it) if such a thing exist, is possible, or even profitable, it would not really be creating the energy.

Of course, I may go totaly of the path and say there would be the void, the absence of "inside" space or time that seperated the two spaces, where no energy or matter as such could exist, but who knows if you could get anything form such a nothing, or if it was possible, would it be controllable, or would it be a choice between a Big bang or rip like event...But that probably does not make much sense...

By the way, a Perpetual motion device does not really have to give you energy you can use for anything, it only needs to keep itself running perpetually without outside interference, of course, that is easier said than done...