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Author Topic: Is perpetual motion impossible?  (Read 59333 times)

lyner

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Is perpetual motion impossible?
« Reply #75 on: 18/11/2008 09:14:24 »
There must be some force to turn your wheel. This will have to come from the imbalance in moments. A thousand designs have relied on this and they all failed - of course. What else can happen?
Do you seriously not subscribe to Energy as a concept - and all that implies?

And here's a thought. Would not Evolution have produced living organisms, based on your idea, if it were really viable?

What saddens me is that, when your next machine runs down, you will simply blame it on practicalities and not on fundamentals. Why not direct your undoubted enthusiasm and energy into a more fruitful direction? Perhaps into improving efficiency of a 'realistic' system.


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Well I kinda turn metal into gold, its my living as a blacksmith/armourer.
I like it.
 

Offline Andrew K Fletcher

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Is perpetual motion impossible?
« Reply #76 on: 18/11/2008 09:22:32 »
Thought experiments. Could a system be built that relies on energy burned converting it back to the original source, separating back into combustible gas and oxygen.

This is something the planet achieves so must be possible to replicate on a smaller scale.

Hydrogen extracted from water produces water, which can be burned again and again without any net loss. Figure out how to separate the water without using as much energy as the gas releases to our engine and we could have some form of perpetual motion.

So if say our proposed perpetual machine was a boat that converted the water into gas to fuel an engine using less power than the conversion process would this qualify?
 

Offline rosy

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Is perpetual motion impossible?
« Reply #77 on: 18/11/2008 10:58:36 »
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This is something the planet achieves so must be possible to replicate on a smaller scale.

Yes, but the planet has an external source of energy.

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Hydrogen extracted from water produces water, which can be burned again and again without any net loss. Figure out how to separate the water without using as much energy as the gas releases to our engine and we could have some form of perpetual motion.
Fundamental misunderstanding of how chemistry works. The (theoretical) amounts of energy required to generate the reagents and released by the reaction are exactly equal. Unfortunately thermal losses during for example the process of splitting the water by electrolysis (or any other method) will never be zero, so we can never even break even on this or any equivalent chemical process.
 

lyner

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Is perpetual motion impossible?
« Reply #78 on: 18/11/2008 11:21:56 »
AKF
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Hydrogen extracted from water produces water, which can be burned again and again without any net loss. Figure out how to separate the water without using as much energy as the gas releases to our engine and we could have some form of perpetual motion.
When I was little I though I would be able to fly by waving two table tennis bats as I jumped down from the table. I grew up and learned the facts of life.
How can you say there's no net loss? Energy has to be supplied (EXTRA energy) each time you repeat the cycle because of losses.  During every energy transfer, there is some Heat generated. Some of this, with the best insulation you can supply, will  be lost to the system. The Efficiency  in any process is not 100%. Why not accept that? There is even a net loss of Hydrogen and Oxygen as they combine, to a finite degree, with the material of the containers used.
Perhaps you should 'figure out'  the facts and learn some Science (not Magic).
I know that the actual facts don't influence your particular views and Science is 'all out to get you' but give it a try.
 

Offline Andrew K Fletcher

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Is perpetual motion impossible?
« Reply #79 on: 18/11/2008 11:57:12 »
Thank you Rosy.

It is not wise in science to say we can never.
This was a thought experiment supposing that a method of hydrogen extraction can be found that greatly lowers the amount of energy used to extract it to the point where an engine can run burning it and the vapour can be recycled back to the tank to repeat the process. Saying we can never achieve this is a bit like stating water under normal atmospheric pressure in a single open ended tube will not rise over the 10 meter mark, in the physics books relied upon by Sophiecentaur et al.

So let's deal with the external source of energy. Where does the energy from the sun come in to driving our hypothetical hydrogen engine?

Let's not forget the original idea of perpetual motion. It was to produce a widget that could output more energy than it uses to allow it to continue running indefinately. Should the object deteriorate over a year but still runs for that year perpetually we have not disproved perpetual motion but have merely exposed a flaw in the widget construction.

Sophiecentaur. Predicatably you throw up a defence. The net loss was in the amount of water used. In that once burned it transforms back into water so no net loss of water.

Make the hydrogen production more efficient than the losses due to friction and we can ignore heat loss providing the widget keeps running ofc.

Just thinking aloud here so cut me some slack
 

lyner

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Is perpetual motion impossible?
« Reply #80 on: 18/11/2008 13:04:45 »
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The net loss was in the amount of water used. In that once burned it transforms back into water so no net loss of water.
That's like saying that there is no 'net loss' of bicycle chain when you ride a bike. Almost true (apart from wear and tear) but irrelevant when we are discussing energy and efficiency, surely.

So, if we allow efficiency to be greater than 100%, we have free energy. Where does that statement get us? It doesn't mean that 101% efficiency is a concept worth considering.
 

Offline AB Hammer

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Is perpetual motion impossible?
« Reply #81 on: 18/11/2008 13:10:14 »
Andrew K Fletcher

Here some video that may help you stand.

E=mc2 (part I)

E=mc2 (part II)
feature=related

 

Offline rosy

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Is perpetual motion impossible?
« Reply #82 on: 18/11/2008 13:56:07 »
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It is not wise in science to say we can never.
OK, I forgot to state explicitly that I was assuming we don't need to rewrite thermodynamics from the bottom up. I make this assumption because the evidence supporting thermodynamics is about as cast iron as it gets. Naturally it's possible if someone bangs their head against it for long enough they may discover a flaw... but I suggest they're more likely to get concussion.

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Saying we can never achieve this is a bit like stating water under normal atmospheric pressure in a single open ended tube will not rise over the 10 meter mark, in the physics books relied upon by Sophiecentaur et al.
Yawn. Andrew, this is still not a particularly remarkable result. A column of water is only supported by the atmosphere to 10m under a vacuum, but if there are interactions with the walls of the column it may be transiently stable to a greater height. King Charles's Head (http://en.wiktionary.org/wiki/King_Charles'_head) comes to mind.

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So let's deal with the external source of energy. Where does the energy from the sun come in to driving our hypothetical hydrogen engine?
Uh? Well, you could use it to drive a solar cell to electrolyse the water. But it's not PM because it depends on an external energy source.
 

Offline AB Hammer

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Is perpetual motion impossible?
« Reply #83 on: 18/11/2008 14:15:09 »
This just a thought to add.
How the term "free energy" rakes against my nerves.
It would best be called "over unity investment"
You still have to spend money for the windmills, solar panels, the materials of whatever we use to collect the available energy. Then it finally pays for itself from freeing you from spending that much money to the power grid. So you get more back from you investment. More out than in = over unity.  [:o)]
 

Offline Andrew K Fletcher

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Is perpetual motion impossible?
« Reply #84 on: 18/11/2008 18:28:46 »
The video's were good enjoyed them Thanks.

Looking at the title of the thread, we are trying to show that perpetual motion is possible. Reference to perpetual movement of planets suggests that PM is not impossible but probable. And that the bar against it is the level of our current knowledge.

A comet for example appears perpetual as it travels through space, so we should consider a vacuum and zero gravity to remove friction from the widget. Super cooled magnets from memory are able to reduce friction between a track and a monorail train, think it was in Japan. So there are many ways to get over obstacles.
 

Offline Bored chemist

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Is perpetual motion impossible?
« Reply #85 on: 18/11/2008 19:58:04 »
"Reference to perpetual movement of planets suggests that PM is not impossible but probable."
Come back in 10 billion years and you will find that it's not perpetual.

"Super cooled magnets from memory are able to reduce friction between a track and a monorail train,"
Since there's no contact the friction losses are zero. However there are losses due to viscous drag; losses due to electromagnetic induction and, probably other losses too.

The bar here is your current knolwedge. If you knew some physics you wouldn't waste time on this pipedream.
"So there are many ways to get over obstacles."
Yes, but there is no way to get over the laws of thermodynamics.
 
 

Offline Andrew K Fletcher

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Is perpetual motion impossible?
« Reply #86 on: 18/11/2008 21:19:05 »
BC You remind me of a scene from Red Dwarf where the despair squid has infected the crew. They have one bullet left, so line up to allow the single bullet to kill them all and put them out of their misery. Blakey from On The Buses was another that reminds me of your negative attitude.

All we are doing is throwing around a few ideas that might stimulate some interesting conversation, the topic is interesting, whether or not you feel it disagrees with the laws of thermodynamics.

Stating that 10 billion years is required to prove or disprove a perpetual motion machine is hardly worthy of a round of applause
 

Offline Bored chemist

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Is perpetual motion impossible?
« Reply #87 on: 18/11/2008 22:16:50 »
"Stating that 10 billion years is required to prove or disprove a perpetual motion machine is hardly worthy of a round of applause"
I'm not after a round of aplause, I'm after scientific discussion on a scientific website.

We could talk about 6 foot pink bunny rabbits, but whom would this help?
You seem to think that I'm negative and that this isn't productive.
How productive is the delusional notion that perpetual motion machines are possible?
 

Offline srobert

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Is perpetual motion impossible?
« Reply #88 on: 18/11/2008 22:40:15 »

Perpetual motion in my mind is a device which will continue in motion without the aid of any additional energy from an outside source other than that which it was given at the time the device started to move. Which in theory is possible however to achieve it and prove itself it would need to be in a closed system in order to eliminating all outside influences.
 

Surely perpetual motion of itself is not by any means impossible, a body at constant velocity will remain at constant velocity unless acted upon by an unbalanced force. An example of an unbalanced force which acts upon bodies we typically come across is friction. If you were to remove all friction, as well as any other forces from affecting the object then it will not stop. In practice that's impossible since at the very least it will be affected by the gravitation field of other ojects.

The real problem is to build a machine from which you can extract work perpetually without the input of energy

srobert
You've just described two non viable situations. The latter is just a bit more outrageous than the former.
btw, the gravitational bit is not strictly relevant because gravity is a conservative force.

What's wrong with my first statement, since it's just a statement of Newton's first law which I was taught as "A body continues to maintain its state of rest or of uniform motion unless acted upon by an external unbalanced force." All I said was that there's no law broken if all external unbalanced forces can be eliminated. Of course in practice this is essentially impossible, but unless you're telling me Newton's first law is wrong at low velocities, or I've mis-remembered it where have I gone wrong?
« Last Edit: 18/11/2008 22:50:37 by srobert »
 

Offline AB Hammer

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Is perpetual motion impossible?
« Reply #89 on: 18/11/2008 22:50:16 »
Bored chemist

Impossible or possible, this is the meaning of the string.
You take my design I posted. If the shooter design shoots the ball from the 8:00 position up towards the 2:00 position which will hit most likely at the 3:00 position due to weight displacement. The wheel will rotate as long as the shift for the shooter shoot around the 8:00 position for each ball. Thus this perpetuation of the motion which mean shoot and shift on time.

 If this happens it will run until it is stopped or break down. Is this not perpetual motion if this happens? According to the patent office it would be.  
 

lyner

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Is perpetual motion impossible?
« Reply #90 on: 19/11/2008 07:56:23 »
I don't think we'll find a supercooled magnet which requires no energy and we won't find a region of space with no atoms in it. So neither of those scenarios are anything but 'limiting cases' for a totally academic argument.
As for actually getting energy out of a perpetual machine, there's little point in discussing it if it won't even self-sustain.
Red Dwarf is great fiction; so is PM. They go together well but RD is more fruitful.
« Last Edit: 19/11/2008 22:08:25 by sophiecentaur »
 

Offline nicephotog

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Is perpetual motion impossible?
« Reply #91 on: 23/11/2008 11:15:12 »
  blakestyger said:  ..."Yes - everything has to be paid for!"..

The above are all very well
BUT THEN WHAT IF SOMEONE" ACTUALLY DID PAY FOR IT!"
and thus...
 

lyner

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Is perpetual motion impossible?
« Reply #92 on: 23/11/2008 11:30:41 »
.... and thus there would be an input.
 

Offline Bored chemist

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Is perpetual motion impossible?
« Reply #93 on: 23/11/2008 13:11:23 »
Bored chemist

 
 If this happens it will run until it is stopped or break down. Is this not perpetual motion if this happens? According to the patent office it would be.  
If it were perpetual motion then it would be perpetual motion.
Since it won't work (due to friction etc), it won't be perpetual motion.
 

lyner

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Is perpetual motion impossible?
« Reply #94 on: 23/11/2008 13:21:01 »
I wonder why are we replying to this nonsense?
It won't work.
'They' will have to waste a lot of time to prove to themselves that it won't work - but, even then, they will say that a practical detail was to blame when it fails.

It's like people at Monte Carlo with a 'system'. You just can't tell 'em.
 

Offline AB Hammer

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Is perpetual motion impossible?
« Reply #95 on: 23/11/2008 15:04:24 »
It is not always the quest but, it is what you learn from the quest. Many many inventions have come from this quest that have helped change the world or had lead to others that have. I myself have 4 inventions that have come from this quest. One I am presenting for contract with the US military, but it has many other uses as well. (it is not a weapon)

 PS Bored chemist
That is a blanket answer. You didn't truly answer the question.

 
 

lyner

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Is perpetual motion impossible?
« Reply #96 on: 23/11/2008 15:07:02 »
So the means justify the end, so to speak?
 

Offline AB Hammer

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Is perpetual motion impossible?
« Reply #97 on: 23/11/2008 15:10:35 »
  blakestyger said:  ..."Yes - everything has to be paid for!"..

The above are all very well
BUT THEN WHAT IF SOMEONE" ACTUALLY DID PAY FOR IT!"
and thus...

Lets ask about energy? can you destroy it? No you can only change it. everything is a cycle. The cycle of life ect. For perpetual motion you are just containing it in a smaller space.
 

Offline AB Hammer

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Is perpetual motion impossible?
« Reply #98 on: 23/11/2008 15:20:09 »
So the means justify the end, so to speak?

 Every action has an equal and opposite reaction. 1 action causes another reaction which causes anther reaction in a closed loop could become perpetual.

For my hobby. The enjoyment justifies the hobby, the rest are just fringe benefits. Here is a youtube video I did with magnets
You should find it an interesting effect. Regular steel bar above holding a regular steel ball above the magnet without touching a magnet. I am sure I can show many slide of hand magic tricks  that can incorporate the effect.
 

lyner

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Is perpetual motion impossible?
« Reply #99 on: 23/11/2008 17:21:13 »
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I am sure I can show many slide of hand magic tricks
No doubt. What has that got to do with a genuine demonstration of PM?
What have 'reaction and action' got to do with energy transfer? Does a dropped ball bounce for ever?
 

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Is perpetual motion impossible?
« Reply #99 on: 23/11/2008 17:21:13 »

 

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