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# New (?) perpetual motion idea

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Are you saying that this doesnt constitute perpetual motion because the falling weights supply energy?

The falling weights don't supply any energy. If the machine were to run it would only move potential energy from one weight to the next. There would be no production of energy. The machine will not run because energy is lost in the friction of the machine and that consumes what ever energy you put into it to get it moving in the first place. Again, the Second Law of Thermodynamics states that "in all energy exchanges, if no energy enters or leaves the system, the potential energy of the state will always be less than that of the initial state."

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Many previous posts in this and other threads have given good explanations of the impossibility of perpetual motion machines. However, I think that to understand these explanations, one needs to know some physics basics definitions and principles

The fundamental quantities in physics are:

• $\mbox{mass}$
• $\mbox{distance}$
• $\mbox{time}$

From this, we define:

• $\mbox{velocity} = \Delta \mbox{distance} / \mbox{time}$
• $\mbox{acceleration} = \Delta \mbox{velocity} / \Delta \mbox{time}$
• $\mbox{force} = \mbox{mass} \times \mbox{acceleration}$
• $\mbox{energy} = \mbox{work} = \mbox{force} \times \Delta \mbox{distance}$

$\Delta$, pronounced “delta”, means change in a quantity. For example, “January 19, 2009 6:50:00 PM GMT” and “January 19, 2009 6:53:15 PM GMT” are times, their delta is 195 seconds.

Other principles don’t lend themselves to definition with simple formulae. An important one, possible the most important one is

• “simplification” – when making calculations, one can chose simple, but entirely accurate one, over more complicated ones

If one has a good working grasp of these definitions as principles, the impossibility of perpetual motion machines is intuitive and obvious. I’ll now use them to address a few of ozi-rock’s questions.

am I right in saying that if there was no other forces on it other than those of the weight it would keep spinning?
Yes. Any physical system – bodies traveling in space, wheels, pendulums, etc. – will continue doing what it’s doing if no forces act on it, because $\mbox{force} = \mbox{mass} \times \mbox{acceleration} = 0$ means $\mbox{acceleration} = \Delta \mbox{velocity} / \Delta \mbox{time} = 0$, which means $\Delta \mbox{velocity} = 0$, which can be rephrased “nothing changes”.

This also holds if the system is subject to forces, but the forces are exactly equal and opposite. Because objects resting on the surfaces on planets, such as the “unbalanced wheel” and axle in question, are subject to the force of gravity, this applies to them.

I mean it would keep getting energy from the falling weights?

Could it not be possible to overcome these forces with greater ones?

Here the simplification idea is important.

In a physical system like weights on a wheel, an elevator, etc., how the weight get from one height to another doesn’t matter. Because the force of gravity is always downward, only distance in the up-down direction is multiplied by it. The acceleration of gravity near the Earth’s surface is about 9.8 m/s/s, so its force on a 1 kg weight is about $\mbox{force} = \mbox{mass} \times \mbox{acceleration} = 1 \,\mbox{kg} \times 1 \,\mbox{m/s/s} = 9.8 \,\mbox{kg m/s/s}$. To reduce writing, the unit kg m/s/s is called the Newton, abbreviated N. The wheel lowers and raises the weight the same distance with each revolution. Let’s say this distance is 1 meter. For its downward trip, then $\mbox{energy} = \mbox{work} = \mbox{force} \times \Delta distance = 9.8 \,\mbox{N} \times -1 \,\mbox{m} = -9.8 \,\mbox{N m}$. Again, the unit N m, has a short name named after a famous scientist, the Joule, abbreviated J. For the weight’s upward trip, $\mbox{energy} = \mbox{work} = \mbox{force} \times \Delta distance = 9.8 \,\mbox{N} \times +1 \,\mbox{m} = +9.8 \,\mbox{J}$. So, for the entire revolution, $\mbox{energy} = \mbox{work} = -9.8 \,\mbox{J} +9.8 \,\mbox{J}= 0 \,\mbox{J}$. No energy is used or created, no work done.

Here the “simplification” principle is important. With the unbalanced wheel, with its arms, hinges, and stops, the upward and downward path of each weight, and thus its up-down and left-right distance and work/energy done/used, is complicated. We don’t need to calculate all this, though, only calculate work/energy for each revolution.

Nearly all perpetual motion machine claims invite the reader to attempt the more complicated calculations, or worse, not calculate them, but try to imagine them. Because they’re complicated, nearly everyone attempting them will make a mistake, finding that the machine does negative work/gains energy with each cycle of the machine. The reader’s mistake, however, is not physically real, and the machine really behaves as described by simple calculations, or by complicated ones performed without mistakes.

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Thank you very much for the detailed reply CraigD, you definitely know how to clarify a situation, I'll work on a few more calculation's based on what you've told me when I get some free and hopefully I'll get a better understanding of all these thing's

Thanks again,

Oisin

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• 2 months later...

I usually lose interest as soon as I read "it doesn't work now but it will definately work in vacuum".

Anyway, it is probably impossible to create a perpetual motion machine as defined in the dictionary, but what if we could create a machine that appears to be perpetual? Not to trick people but to really use the machine to do useful work for us without requiring any energy source or fuel that we can see or know of. We should not assume that we have discovered or detected all possible energy sources that could be used for our benefit via a machine of some sort. There could be a lot more around us than we think. All we need to do is convert it to a usable form of energy for us and hope it will never run out.

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Well, there are machines that do something similar to that already, TEguy, there's a factory in japan that uses mechanisms close to the ones that were used in karakuri ningyo dolls. The factory produces transmissions, and they use carts that use the weight of the transmission to propell the cart forward while compressing a spring that after the cart transports the transmission a few yards to another assembly line, returns the cart back to it's original position, then another transmission goes on it, and the process repeats itself, just like in the karakuri dolls. It's actually fairly efficient, not perpetual motion, but is this the kind of thing you were thinking of, TEguy

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That is the coolest mechanism I've ever heard of Alexander, would happen to know the name of the cart? It's exactly the kind of perpetual motion I would be interested in (everyone will probably say it's not perpetual motion but you know what I mean)

I just read the article about the doll's, I love it, the ideas some people have are truly spectacular, thanks for sharing that with us ;)

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Can't find it anywhere on the net... i will try youtube to catch perhaps that episode or something, but for the life of me, i cant find any references to that factory anywhere now ;)

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Don't worry about it Alexander, I wouldnt want you wasting your day looking for it, if I find it I'll post a link here, thanks again, it's a great idea for transporting things ;)

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It was on one of those science channel shows, either beyond tomorrow, what the ancients knew or something...

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thats not quite what I meant but a very cool concept nonetheless

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Well, there are machines that do something similar to that already, TEguy, there's a factory in japan that uses mechanisms close to the ones that were used in karakuri ningyo dolls. The factory produces transmissions, and they use carts that use the weight of the transmission to propell the cart forward while compressing a spring that after the cart transports the transmission a few yards to another assembly line, returns the cart back to it's original position, then another transmission goes on it, and the process repeats itself, just like in the karakuri dolls.
Though clearly not perpetual motion – you’ve got to lift weights into it, in the case mentioned, heavy vehicle transmission units, to power it – these sound pretty neat and useful. I imagine they’re something like a railway handcar, though the closes thing I could find via a short web search is this youtube video.
Not to trick people but to really use the machine to do useful work for us without requiring any energy source or fuel that we can see or know of. We should not assume that we have discovered or detected all possible energy sources that could be used for our benefit via a machine of some sort.
As best I can tell, attempts to make machines powered by unknown or unused energy sources are usually termed “free energy” rather than “perpetual motion” machines.

Depending on ones definition of “free energy”, such a machine can be anything from

• conventional photovoltaic cells - sunlight, after all, is effectively unlimited and free

to

• “cold fusion” machines, which purportedly transmute the hydrogen in ordinary water into helium, releasing energy, and which at present appear to or practically impossible or so low-power as to be useless

to

• ”zero-point”, or “vacuum” energy devices, which are in principle possible – Casimir effect measuring experiments routinely measure a force which, were it allowed to move the measuring devices plates, would produce measurable one-time releases of energy – but at present appear to have no means by which they can being “scaled up” into practical power sources – although some interesting, though largely disproved proposals have appeared, such as “sonoluminescent Casimir energy”, an idea championed for a time by Julian Schwinger, and, as I recall, independently by some disreputable Russian Engineer.

Though I understand the consensus is that sonoluminsecence can’t be used to obtain ZPE, the idea is an interesting one. In short, the idea is that, by using sound to generate very small bubbles in a liquid, once can create many small gaps equivalent to the large metal plates used in Casimir effect experiments, and that the collapse of the bubble – which produce the light discharges for which sonoluminsecence is named – perform more mechanical work than is put into the system in the form of sound, which could be extracted as useable work thought, for example, a simple heat engine.

Though no experiment to date appears to have shown that any means of extracting practical, large amounts of ZPE exist, I don’t believe it’s been compellingly shown to be theoretically impossible. The implications were such a device possible, are complicated.

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Very interesting, I dont quite understand zero point energy but from what I read about it, it is very promising. I like your last sentence though, the implications are indeed complicated.

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• 4 months later...

This won't work...energy in various ways throughout that process, resulting in a "leak" in the system. Theoretically, it could be done if everything worked at 100% efficiency, but it's not like you have an unlimited supply of energy you can tap into. You'd just be removing energy from your system.

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Well, we all know that the maximum theoretical efficiency of any machine can not exceede 100% and 100% is only possible in a frictionless universe. Though some systems seem to exceede this, as an example, the black-bird, since the engine was partly driven by the air compression, and the front shroud of the engine could move in and out providing more or less air pressure on demand, at full speed 80% + of the thrust that the engine produced was produced by the air pressure on the compression blades on the front of the engine, this is opposed to 20% or less in subsonic operation, thus the faster you went the more fuel you saved.

Even though this seems counter-intuitive, it's not, just simply that the faster you went, the more efficiently energy regeneration techniques made the engine operate, and it also does not mean over 100% mechanical efficiency as fuel was still burned (and at astounding rates).

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) Time is homogeneous.

2) Noether's theorems.

3) Mass-energy is locally conserved.

4) No Type I perpetual motion machines (net gain).

5) Second Law of Thermodynamics - Carnot efficiency.

6) No Type II perpetual motion machines (zero loss).

End of perpetual motion machine discussion, again. Mechanism is irrelvant.

Diamond has negative work function into vacuum, osmium has a 5.93 V work function into vacuum. Rig a vacuum diode with an emitter diode plate studded with CVD Type IIB diamond spicules and an anode receiver plate of coated with osmium. Electrically short externally. It runs forever, the two electrodes never reaching thermal equilibrium, every electron transferred delivering 6 eV of energy. So? It is a heat engine and you can get no more work out of it than Carnot allows.

The examples of "perpetual motion" offered above are reprehensible. There is no cheating within conservative fields. What you can get at 100% efficiency is determined by start and end not path. potential energy = mgh, electrical energy = IVt, kinetic energy = (mv^2)/2. Do you see any path specifications in there?

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• 1 month later...

Oh Im sure perpetual motion is possible. If your interested in some free energy projects check out SPAMLINK REMOVED

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Well, sorry Steve, but you're wrong.

If you're serious about engaging in discussion here, please do a search in Hypo regarding perpetual motion machines and thermodynamics in general and you'll understand why it is not workable.

But please - don't spam us in order to generate traffic to your site.

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