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Brainlet here

Anonymous Fri 18 Oct 13:57:21 2019 No.11070242 View Reply Original Report

Quoted By: >>11070606 >>11070668 >>11070708 >>11070986 >>11073573 >>11073947

So why exactly is a perpetual motion machine impossible?

Anonymous

Anonymous Fri 18 Oct 2019 14:09:58 No.11070279 Report

Quoted By: >>11070451

Entropy

Anonymous

Anonymous Fri 18 Oct 2019 14:12:19 No.11070286 Report

Quoted By: >>11070629

Smokey, this is not 'Nam! There are rules!

Anonymous

Anonymous Fri 18 Oct 2019 14:15:34 No.11070301 Report

Quoted By: >>11074006

whenever matter interacts, there's an exchange of energy e.g. friction. whenever this energy becomes heat i.e. increased randomized motion of particles, it dissipates away and is forever irrecoverable (technically, most probably).

Anonymous

Anonymous Fri 18 Oct 2019 14:56:37 No.11070451 Report

Quoted By: >>11071318

>>11070279
This.
They all either violate the first or the second laws of thermodynamics or both.

Anonymous

Anonymous Fri 18 Oct 2019 15:31:36 No.11070606 Report

Quoted By:

>>11070242
watch this
https://youtu.be/rckrnYw5sOA
tl;dr : actually quantum mechanics forbids this

Anonymous

Anonymous Fri 18 Oct 2019 15:38:44 No.11070629 Report

Quoted By: >>11070681

>>11070286
There can only be “rules” if someone wrote them. Think about it. “Limits” aren’t prime movers, they are an invention.

Anonymous

Anonymous Fri 18 Oct 2019 15:50:34 No.11070668 Report

Quoted By:

>>11070242
because some integral is always non-negative or something

Anonymous

Anonymous Fri 18 Oct 2019 15:58:04 No.11070681 Report

Quoted By:

>>11070629
>There can only be “rules” if someone wrote them. Think about it. “Limits” aren’t prime movers, they are an invention.
Conservation of energy is a "rule" you can choose not to follow? Good to know

Anonymous

Anonymous Fri 18 Oct 2019 16:09:45 No.11070708 Report

Quoted By:

>>11070242
Whatever drives a machine must flow from high to low. Unless your high is infinite and your low is bottomless, and the process always overcomes all the losses involved, it will come to an end.

Anonymous

Anonymous Fri 18 Oct 2019 17:57:52 No.11070986 Report

Quoted By: >>11071239

>>11070242

It's not. You can just never get any work out of one, as then it would lose energy, requiring you to put in energy from an outside source.

Anonymous

Anonymous Fri 18 Oct 2019 18:13:50 No.11071037 Report

Quoted By:

Because nature is reflexive.

Anonymous

Anonymous Fri 18 Oct 2019 18:19:48 No.11071047 Report

Quoted By: >>11071239

An actual perpetual motion machine isn't theoretically impossible but it'd only be useful as a battery. Getting work out if it takes energy.

Anonymous

Anonymous Fri 18 Oct 2019 19:35:20 No.11071239 Report

Quoted By:

>>11070986
>>11071047
they are actually impossible
due to the Heisenberg Uncertainty Principle all system will lose energy

Anonymous

Anonymous Fri 18 Oct 2019 20:01:25 No.11071318 Report

Quoted By: >>11071339

>>11070451
So does that mean 99% efficient machine is possible, just not one that moves infinitely? for example, one that can spin/move for a very long time, but not forever?

Anonymous

Anonymous Fri 18 Oct 2019 20:09:14 No.11071339 Report

Quoted By: >>11071343 >>11071357

>>11071318
No. The maximum thermal efficiency of a heat reservoir between two temperatures Thi and Tlo is always only to be less than 1-Tlo/Thi. This is Carnot's theorem.
Things can move for an infinitely log time, sure. No problem with that. A flywheel spun in the vacuum of outer space will spin forever. However:
It is impossible to extract more energy from a system than you put in (first law of thermo)
It is impossible to extract energy from a single heat reservoir (second law of thermo).

Anonymous

Anonymous Fri 18 Oct 2019 20:10:57 No.11071343 Report

Quoted By:

>>11071339
***heat engine between two temperatures
The second law should say "it is impossible to extract energy from a single reservoir without affecting another reservoir"

Anonymous

Anonymous Fri 18 Oct 2019 20:17:54 No.11071357 Report

Quoted By:

>>11071339
>Things can move for an infinitely log time, sure. >No problem with that.
this is only true in classical mechanics
in reality even a perfectly isolated system must radiate heat due to the intrinsic random motion of its internal particles

Anonymous

Anonymous Sat 19 Oct 2019 02:11:55 No.11072226 Report

Quoted By:

bcoz eternity exists

Anonymous

Anonymous Sat 19 Oct 2019 15:15:58 No.11073573 Report

Quoted By:

>>11070242
there's a finite amount of energy in the universe, a perpetual motion machine would have to get energy somewhere to keep going against friction.

Anonymous

Anonymous Sat 19 Oct 2019 17:53:27 No.11073947 Report

Quoted By:

>>11070242
no such thing as a free lunch, you can't make shit out of nothing my guy

Anonymous

Anonymous Sat 19 Oct 2019 18:15:18 No.11074006 Report

Quoted By:

>>11070301
and if something were done to recover these particles that go away from their initial state (and disperse) ... if there was something that could contain that something being matter would be subject to entropy. Is there anything that goes against entropy? Antimatter?

Anonymous

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Anonymous Sat 19 Oct 2019 18:51:58 No.11074120 Report

Quoted By: >>11074689 >>11074725

OP you need to understand that the universe has a finite amount of mass-energy. 4*10^69 J is all the energy that exists in the universe. There will never be any more than this.

When you change 1 form of energy into another form of energy you will lose a small amount of energy that gets lost in the conversion.

It doesn't really gets lost as in "deleted" but instead it gets converted to something called "waste heat" it basically means that the energy became entropic.

To visualize what happens think of it as the energy being scattered very thinly and if you want to gather that energy to use it then the act of gathering that energy wastes more energy that the amount of energy you retrieved so you can never gain anything from trying to gather that lost entropic energy.

This happens EVERY time energy changes its shape so over time in our universe every Joule of energy will slowly become "entropic energy".

A perpetual motion machine would generate Joules but something like that isn't how our universe works at all. Instead our entire universe is just diffusion of energy into different forms towards a higher and higher rate of entropy.

Time itself is an effect of entropy always having to increase. This is why the arrow of time always moves in just one direction. Because the total entropy always has to increase.

I hope this gives a more broad answer to your question rather than just "entropy" or "2nd law of thermodynamics"

Anonymous

Anonymous Sat 19 Oct 2019 22:02:45 No.11074689 Report

Quoted By: >>11074702

>>11074120
Is there anything that goes against entropy? Antimatter?

Anonymous

Anonymous Sat 19 Oct 2019 22:07:58 No.11074702 Report

Quoted By: >>11074725

>>11074689
Nope. You can reverse entropy but it will always result in just more entropy somewhere else so the total entropy always increases no matter what you do.

Antimatter is just another form of mass-energy to create anti-matter you would generate waste heat. There's basically nothing you can do to fight this.

The best thing you could do is minimize entropic events such as stars burning. So as humanity gets more advanced we will most likely start a crusade to turn off all stars in the universe as they waste a lot of energy towards entropy which we will never be able to use. This way we can elongate our existence as a species as long as possible. But eventually entropy IS going to catch up to us and everyone else in this universe as the last bit of joule gets wasted as well and the universe stays as a pitch black husk for all eternity.

Anonymous

Anonymous Sat 19 Oct 2019 22:12:40 No.11074725 Report

Quoted By:

>>11074120
>>11074702
This was a profoundly philosophic response, I enjoyed reading it.

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