Can a Perpetuum Mobile Exist According to the Laws of Conservation of Energy?

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In summary: Well, if what you want to do is reach absolute 0, then almost reaching absolute 0 is still a significant accomplishment.
  • #1
Mattara
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According to the laws of Conservation of Energy, there can be no such thing as a perpetuum mobile of any kind.

The purpose of this topic is not no disprove them in any kind.

But then i began to think:

A battety re-charger is powered by a battery which in turn runs the battery recharger.

This theory alone will of course not work, but as in all sciences we have the "what if" variable.

Lets say we make that circut frictionless and but it into complete darkness in absolute vacuum at 0 K. Would that run forever?

(Of course there is not absolute vacuum anywhere in the universe)

What part of this line of thought is inaccurate from my part?

And how about Big Bang, was energy created there? Energy must surley have come from something in the beginning?
 
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  • #2
Air, or the lack thereof, has essentially no effect upon electrical circuits. What you want is superconductivity, for which temperatures near to 0 K are required. The circuit that you propose, if superconducting, might just keep a current flowing around in a loop, but there's no way that you could extract any work from it.
 
  • #3
Not only that, but there's also ANOTHER problem. While your wires might be superconducting, your connectors and internal parts of the batteries are NOT! Ohmic losses are still inherent in such a thing.

I'm not sure why we're bothering with such a system. An atom is technically a "perpetual" something. However, to get any effect (work, energy, etc) out of it, it must INTERACT with something, and this is where energy transfer occurs and the "perpetualness" no longer applies. The same with a superconducting loop. By itself, it is useless and it isn't a "machine". When you interact with it to get energy out of it, that is when it will start losing energy and diminish its perpetualness.

Zz.
 
  • #4
Ah, i see!

Thanks for the tourough replies!
 
  • #5
My thanks to Zapper as well, for pointing out something that I hadn't thought of. You can't have a superconducting battery. Any chemical activity would cause resistance. I'm not so sure about the connections though; if there could be a perfectly smooth interface between two components (as in Johanson blocks--and I probably spelled that wrong), then I'd expect it to act as a single continuous conductor. More input, please, Mr. Z. :smile:
 
  • #6
Danger said:
My thanks to Zapper as well, for pointing out something that I hadn't thought of. You can't have a superconducting battery. Any chemical activity would cause resistance. I'm not so sure about the connections though; if there could be a perfectly smooth interface between two components (as in Johanson blocks--and I probably spelled that wrong), then I'd expect it to act as a single continuous conductor. More input, please, Mr. Z. :smile:

I'm not familiar with Johanson blocks. However, quantum mechanically, when a superconductor comes in contact with a normal-state metal, you get a discontinuity in the boundary conditions at the junction. You can get a number of effects, including the proximity effects here. The supercurrent wavefunction can undergo a number of things, including something called Andreev scattering. The charge careers can get "reflected" off the boundary. So even with a perfect connection, you still lose.

Zz.
 
  • #7
You can never win, you can only break even

You only break even at absolute zero

You can never reach absolute zero

marlon
 
  • #8
Hi Marlon. You wouldn't believe how many times I've wanted to post that, and always managed to restrain myself. :smile:
ZZ, the blocks that I mentioned are slabs of steel that are so finely machined that they stick to each other. As far as I know, their only practical use is to demonstrate Van der Waals forces. For the sake of clarification, I had assumed that every component in the system was superconducting, with no 'normal state matter' present. It seemed to me that in such a case, the current wouldn't 'realize' that there was a junction present.
 
  • #9
marlon said:
marlon You can never win, you can only break even

You only break even at absolute zero

You can never reach absolute zero

Well, we are very close to reaching absolute 0 already.

The superconductive electromagnets in the LHC (Large Hadron Collider) or the previous Large Electron Positron collider (LEP) at CERN will have/had them cooled to (correct me if i am wrong) not more than a very few degrees over 0 K.
 
  • #10
But close is not equal to at. When we're talking about reaching 0K there's a huge difference.
 
  • #11
Not really. It all depends on what you want to do. The heat energy is not that much bigger at 1K that it is at 0K in terms of J
 
  • #12
Mattara said:
Not really. It all depends on what you want to do.
Well, if what you want to do is reach absolute 0, then almost reaching absolute 0 is still a failure.
 
  • #13
Danger said:
Hi Marlon. You wouldn't believe how many times I've wanted to post that, and always managed to restrain myself. :smile:

:smile:

sorry

This answer is indeed the easy (yet correct) way out... It actually covers over 90% of the answers one has to give to thermodynamics questions and especially these perpetuum mobile type questions.

regards
marlon
 
  • #14
But how about Big Bang? Energy/mass must have been created there?
 

FAQ: Can a Perpetuum Mobile Exist According to the Laws of Conservation of Energy?

What is LoCoE?

LoCoE stands for Law of Conservation of Energy. It is a fundamental principle in physics that states energy cannot be created or destroyed, only transferred or converted from one form to another.

What is a perpetuum mobile?

A perpetuum mobile, also known as a perpetual motion machine, is a hypothetical machine that can continue to operate and generate energy indefinitely without any external source of energy. It is considered impossible due to the laws of thermodynamics.

Is it possible to create a perpetuum mobile?

No, it is not possible to create a perpetuum mobile. The first and second laws of thermodynamics state that energy cannot be created or destroyed, and that there will always be some energy lost in the form of heat during any energy transfer or conversion. These laws make it impossible for a perpetuum mobile to exist.

Why do some people claim to have created a perpetuum mobile?

Many people have claimed to have created a perpetuum mobile, but upon closer examination, their machines have been found to have hidden energy sources or to only work for a limited time before stopping. These claims are not scientifically valid and are often based on misunderstandings of energy and physics.

What is the significance of LoCoE and perpetuum mobile in science?

The laws of conservation of energy and the impossibility of a perpetuum mobile have been crucial in advancing our understanding of energy and the universe. They help us to design and develop efficient and sustainable energy sources and technologies, and they also serve as a reminder that we must always be critical and skeptical of extraordinary claims.

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