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Perpetual motion machines already exist

Just Emre's minor misunderstanding then, mistaking a power source which is essentially free for a power source which does not exist. Easy mistake, it seems.
 
This object can also be used to achieve a perpetual motion device:

Reverse Archimedes' Screw Mechanism

"Summary
The phenomenon of a passive metal screw-like object rotating and climbing upwards against flowing water, similar to a screw, is explained by the reverse Archimedes' screw principle. In this system, flowing water strikes the channels of the screw, causing it to rotate. This rotation, in accordance with Newton's third law of motion (action-reaction), "pushes" the screw upwards on the water surface [Physics Stack Exchange]. The object contains no motor or external power source; it is solely the kinetic energy of the water interacting with the helical channel structure that generates the rotation and forward (even upward) motion."

Archimedes' screw sticks motion - GIF - HomemadeTools.net

A small stick spirals up a stream of water, a la Archimedean screw motion . Is this staged? Looks like the stick is being yanked up at the beginning.
www.homemadetools.net
 
Emre_1974tr said:
When scientists oppose the idea of perpetual motion machines, they primarily argue that such machines violate the law of conservation of energy. They state that it is impossible to create energy from nothing and, therefore, mechanisms that can operate continuously and indefinitely on their own are impossible. However, this is where the misunderstanding arises.
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I do not believe this is the case. The law of conservation of energy effectively means a hypothetical perpetual motion machine can't do work. It's the second law of thermodynamics (colloquially, entropy always increases, equivalently heat always flows from the hotter body to the cooler body) that prevents the hypothetical perpetual motion machine from running indefinitely.

The dipping bird works because the head is cooler than the tail. It's the second law of thermodynamics that tells us that, without external intervention, the head and tail will eventually converge on the same temperature and the bird will stop. The water is needed to keep the head cooler by evaporation. Once all the water has evaporated, the head and body will converge to the same temperature and the bird will stop. If you put the bird and a glass of water in a sealed container, the water may not all evaporate but that implies that the net evaporation is zero i.e. it is condensing as fast as it is evaporating which implies that there is no cooling effect on the bird's head. Everything in the sealed container will converge on the same temperature, and once it gets there, the bird will stop.
 
Emre_1974tr said:
If you set up the drinking bird mechanism at the edge of a lake or inside it, or if you place it inside a sealed glass chamber to prevent water from evaporating and escaping, the machine will never stop. In short, as long as the forces or energies that keep the perpetual motion mechanism running continue, it will never cease operation.

Let’s repeat: All perpetual motion mechanisms in history have always utilized existing forces or energies—there is no exception to this rule. However, in ancient times, when no visibly apparent force or energy source, such as human or animal power, was present, a mechanism designed to work with gravity, for example, was called a self-operating machine. But in reality, none of these designs ever relied on the principle of self-operation. They always took something from an external source.

If you examine all famous perpetual motion mechanisms, you will see this truth: At the very least, they always use gravity or another force. Besides the drinking bird mechanism, classic thermometers can also be considered examples of perpetual motion mechanisms. Various machines can be built by utilizing pressure differences or gravity.

I explained all of this in a very old Turkish article of mine:

emre1974tr.blogspot.com

Devri Daim Makineleri Çağına Doğru

20. yüzyılın ilk on yılında motorlu uçaklar, ikinci on yılında da televizyonun icadına şahit olunmuştu. Yüzyılın ortalarında ise uzaya çıkıl...
emre1974tr.blogspot.com emre1974tr.blogspot.com
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If the water cannot evaporate then its cooling effect goes away and the effect stops.

Nobody is interested in what was at one time or another mistakenly believe to be perpetual motion. No one is interesting in reading the various screeds on your blog.
 
Jack by the hedge said:
Just Emre's minor misunderstanding then, mistaking a power source which is essentially free for a power source which does not exist. Easy mistake, it seems.
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This, we all think a perpetual motion machine is one where the maker says the energy source is free or limitless. Emre seems to be saying a machine that converts a source of energy into motion is perpetual.
 
ahhell said:
This, we all think a perpetual motion machine is one where the maker says the energy source is free or limitless. Emre seems to be saying a machine that converts a source of energy into motion is perpetual.
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That may be true. It's often quite difficult to determine what Emre intends. However, I read his post as claiming that various machines were once considered practical equivalents to perpetual-motion machines (or self-operating machines) if they could rely on a practically limitless source of energy. A water wheel in a river that is always flowing is, for many practical purposes, a limitless source of energy to do practical work up to a certain extent. But by the formal definitions that apply to the laws of thermodynamics, you have energy entering from outside the system.

Thermal said:
Anybody got a dictionary handy? The word 'perpetual' seems to be generating a lot of confusion.
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I agree, there seems to be some disagreement on what is meant by a perpetual motion machine. The topic is interesting only insofar as it embodies claims that purport to disprove one or more laws of thermodynamics. While some claimants cleverly disguise energy inputs to create the illusion of perpetuity, it's a completely different thing to try to redefine obviously open systems as a closed system in which we simply ignore the obvious external inputs or the obvious entropy.
 
JayUtah said:
That may be true. It's often quite difficult to determine what Emre intends. However, I read his post as claiming that various machines were once considered practical equivalents to perpetual-motion machines (or self-operating machines) if they could rely on a practically limitless source of energy. A water wheel in a river that is always flowing is, for many practical purposes, a limitless source of energy to do practical work up to a certain extent. But by the formal definitions that apply to the laws of thermodynamics, you have energy entering from outside the system.


I agree, there seems to be some disagreement on what is meant by a perpetual motion machine. The topic is interesting only insofar as it embodies claims that purport to disprove one or more laws of thermodynamics. While some claimants cleverly disguise energy inputs to create the illusion of perpetuity, it's a completely different thing to try to redefine obviously open systems as a closed system in which we simply ignore the obvious external inputs or the obvious entropy.
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Exactly. Solar is, in one sense, a perpetual source of energy, in terms of us being able to use it as long as there are people and Father Sun in the same reference frame. Hardly the physics defying sense of perpetual motion, though.
 
It occurs to me that Emre makes a lot more sense if we look at his writings from a medieval perspective. From that perspective - from before natural philosophy became science - it hangs together somewhat better.
 
I have good news and bad news. The bad news is that I have invented a perpetual motion machine! The good news is that I have forgotten how adjectives work.
 
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