# Why Perpetual Motion Is Not Possible

Discussion in 'Off-Topic' started by DerStrom8, Sep 22, 2012.

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1. ### DerStrom8 Thread Starter Well-Known Member

Feb 20, 2011
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It amazes me how many people have started wasting their time and energy trying to design and build perpetual motion devices, and disregard everything they are taught about energy losses. So I'm starting this thread to hopefully explain why overunity devices are impossible, and why they will fail every time.

We'll start with the first two laws of Thermodynamics. The first law states that:

This means that you cannot have something that makes more "energy" than its input provides. Let's take the common example of a motor and a generator, connected shaft-to-shaft. The motor will spin the shaft of the generator at a certain speed, depending on the voltage and current input. The generator will spin at the same speed, and generate a current proportional to the speed at which it's turning. The generated current will go back into the motor. Okay, so far, so good, right? Now here's the catch: When a current is applied to the motor, the resistance in the motor's coils causes some of the current to be reduced. The energy is often converted into heat at this stage. If you touch a motor that has been running for a while, it will be warm. That warmth is proof that the energy of the mechanical output of the motor is less than the energy that is put into it in the form of voltage and current.

Besides the energy which is turned into heat, some of the energy is also lost due to friction. This goes hand-in-hand with the loss in heat, but it is still different. If you connect just a motor to a battery (and don't put a load on the shaft), the output is still less than the input (simply put). This is because the shaft is still in contact with other parts of the motor, whether it be brushes, bearings, the casing, etc. When any two objects come in contact with each other, friction is created, which means an immediate loss in energy. That also is enough to make perpetual motion impossible.

Finally, there's Newton's 3rd law of motion: For every action, there is an equal and opposite reaction. When the shaft of the motor exerts a force on the generator shaft, the generator pushes back on the motor with the same force. If you don't have a power source to keep the motor moving, the forces will immediately balance themselves out, and no more force will be exerted on either of the shafts. The device would stop dead in its tracks if there is no external force acting upon it.

Also, part of the Second Law of Thermodynamics states that:

We mentioned before that some of the electrical energy is converted to heat in the motor and through friction. Now we know that the heat which was created moves towards cooler areas and dissipates, rather than going back into the device. That energy loss means that the useful energy at the output is less than what we started with, and it will continue to diminish for every cycle.

Now, this example only used the example of a motor connected to a generator. However, these ideas apply to every design for a perpetual motion device. Energy is lost in a form which we cannot use in every setup. It is inevitable. And if energy is lost through one cycle, it will continue to be lost for each consecutive one until it all has been wasted. This, my friends, is why Perpetual Motion is impossible, and why it is a waste of time to try to build one. You cannot defy the laws of physics. They rule our lives, whether you like it or not, and there's nothing you can do to change it.

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2. ### Georacer Moderator

Nov 25, 2009
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It's not like we 're going to have to debate any overunity hothead in the near future, but I 'll keep this link for my boilerplate. Thanks.

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3. ### DerStrom8 Thread Starter Well-Known Member

Feb 20, 2011
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I know you guys are really good at keeping on top of these overunity posts. It's just that I came across one today and I felt I should post this, in case people don't understand why it's impossible.

Of course, my post is extremely simplified, and incomplete. There are many more reasons why it's not possible, but I figured this would give people a good idea, in case they didn't understand.

Regards,
Matt

4. ### Wendy Moderator

Mar 24, 2008
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My analogy is a nuke. It is not overunity, but it illustrates the problem with any device that creates more energy than you put in.

Logic is a weak defense against wishful thinking, unfortunately. Those who want it don't care.

5. ### t06afre AAC Fanatic!

May 11, 2009
5,939
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The nuke releases a lot of energy. It will be wrong to say it creates energy

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6. ### Wendy Moderator

Mar 24, 2008
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Look up the definition of analogy. It is also wrong to say it doesn't create energy. While not creating it from nothingness, it does create energy by the process of conversion. If you could create energy from nothing it would look something like a nuclear device, only it wouldn't stop because the fuel has dispersed.

Last edited: Sep 23, 2012
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7. ### GetDeviceInfo Senior Member

Jun 7, 2009
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so, is the universe, or the largest measure of exsistance, perpetual, or does it give/take energies from yet another source.

It's a twister, but the key is conversion, it only converts, not creating or destroying.

8. ### Wendy Moderator

Mar 24, 2008
20,766
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Ah, now we are into the subject of philosophy, or religion. For the here and now we have to deal with the laws of thermodynamics as they stand.

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9. ### BMorse Senior Member

Sep 26, 2009
2,675
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So they say that a piece of bread with jelly on it always lands jelly side down when it falls, but they also say that cats always land on their feet, so why not strap a piece of bread jelly side up on the back of a cat and drop it and see what happens, will they just perpetually spin without ever hitting the ground? If so, would that make it a perpetually powered device that also has anti gravity capabilities? (sorry, just had to... )

10. ### DerStrom8 Thread Starter Well-Known Member

Feb 20, 2011
2,428
1,328
That came up in a thread some time ago. Whoever mentioned it posted this video:

11. ### shortbus AAC Fanatic!

Sep 30, 2009
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DerStrom, I disagree with you about perpetual motion. It has been proved on AAC!. Look at Loosie's ocean picture, it just keeps going and going and going. He's never stopped talking about it.

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12. ### DerStrom8 Thread Starter Well-Known Member

Feb 20, 2011
2,428
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*GASP* You're right! I stand corrected!

13. ### loosewire AAC Fanatic!

Apr 25, 2008
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That picture some will win me a prize some day,that picture will go down in time as

one of the greatest picture ever posted on the Internet. Man and ocean will become

more popular as years go by, people respect sharks and other dangerous things in

the ocean. At first glance things cross your mind when you see man and rough

water. They want to know why.

May 11, 2009
5,939
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15. ### loosewire AAC Fanatic!

Apr 25, 2008
1,584
435
That chair looks familar,that a great picture. Your computer graphic's

are very good, some day I will say,I know that guy when your work go's

on display for the world and Internet. The Rooster will rule the world before

it all over. I wonder what will happen for you, a chicken and egg movie.

Thank's for all your time you spend making the post,that a great layout.

Wikipedia has photo contest,If any one wants to enter my picture.

The Atlantic Ocean could be considered a land mark. They have the

Bonnet House listed,check it out.

Last edited: Sep 25, 2012
16. ### strantor AAC Fanatic!

Oct 3, 2010
4,302
1,988
Dude you're killing my sales. I had 5 sets of HOJO motor plans ready ship and then you posted this, now they canceled - said no snake oil salesman, ever.

17. ### atferrari AAC Fanatic!

Jan 6, 2004
2,648
764
Hola DS,

Every time I run across this, your thread, I cannot avoid the feeling that you came for preaching at the cathedral where, most probably, non-believers will never come. Unless you try to indoctrinate your followers to spread the word out there.

Additional comment: the attitude of those into OU, not involved in scams but genuinely thinking they have "something", reminds me those that in one way or another "discovered" the "secret" codes in the Z80's instruction set. Kind of "Oh, what a nice thing I got, for free !". Useless for any purpose!

Similarly excited I was when "discovered" two addresses in the RAM bank of the Timex Sinclair 2068 that were not used by the system. I could do whatever I liked with.

That "arcane" knoledge was good for NOTHING. Luckily after short time I gave up on all that.

What I am trying to say is that there, for an invalid reason and here for valid ones, people is wasting time not realizing the lack of usefulness of what they do.

BTW, have you realized that lot of those into OU, do build nice-looking things? They seem to have a lot of time.

Back to my design of a digitally controlled dual DC supply with outputs tracking each other or adjusted independently.

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18. ### Georacer Moderator

Nov 25, 2009
5,142
1,266
I think this thread offers little by now. It did its harm 4 days ago. I think I 'll close it and we 'll chat in all the rest of the offtopic threads.

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