Predictions: at best some incoherent rant that they can but won't do it for some bullshit reason
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So you need to believe, and so repeat while sticking your fingers in your ears. But all the ignoring and childish wailing in the world won't change reality.
It is both a law in books (going back at least 3 centuries) and, much more importantly, a law in demonstrable reality. You can stubbornly continue to choose not to recognize that. I can't stop you, and wouldn't if i could. But i do urge you to reconsider though.
I could, yes - though the "finding" has already been made explicit in this case. What you are obstinately missing is that who measured water's demonstrably flat surface at rest is irrelevant. This isn't about them; it's about you!
Sure - the air itself is a good example. Clouds on a still day are another. If you want to demonstrate it for yourself, get a helium balloon and tie a small weight to it which matches its buoyant force. You seem to be unaware that "floating" (aka neutral buoyancy) is a possible rest state.
All points, however as long as the gas is not at absolute zero it will always be able to expand and overcome that minuscule weight. All a gas must do to expand is cool down.
You stating a thought in your own words is not an explicit finding, I'm sorry to say. If it is a law, then it would be written, as is, elsewhere aside from this forum.
Belief has nothing to do with it, it just simply is
I'm happy to be proven wrong if you can find even a single book stating this law as you have, but it doesn't appear that is possible.
Great example!
If so, why is the air so much thinner at higher altitudes? Shouldn't the gas be able to expand to be a constant pressure/density throughout our livable space, since it's not at absolute zero?
True. However, me repeating the explicit findings of MANY others in my own words doesn't somehow unmake the explicit findings themselves. As much as you desperately (and irrationally, i should urge you to recognize) hope it would :(
As i've said many times now, if you feel the explicit findings (and/or my redescribing of them in intelligible and plain english) are incorrect simply cite or record the measurements demonstrating they are incorrect! The fact that you can't do that (and what that inescapably means) should eventually sink in...
I can, but i won't (because it will only make you a lesser student). This isn't a "contest" to me, and i have no interest in "proving you wrong". It's just a discussion. Many modern hydrostatics textbooks contain the law (albeit in different words) - but if you don't want to read them, so be it. Just don't delude yourself into believing you have read them, or know what they do or do not contain in the meantime!
Good question! It certainly tries to become completely equal in pressure, to the best of its ability (largely dictated by the available thermal/kinetic energy).
The reason it ultimately fails, and the cause of the density gradient in all things - solids/liquids/gasses etc) is because it is being pushed upon by the weight of the gas above it (which ultimately itself is touching, and deriving pressure from the container ceiling).
Consider a sealed gas cylinder at constant temperature, for simplicity. The gas inside seeks equilibrium (rest). The gas expands to fill the container and then the gas settles. The gas above the gas below is settling on top of it! As a result the gas below is at a higher pressure/density - AT equilibrium (at rest).
An analogy that might help is considering a piece of compressible foam. With nothing sitting atop it (aside from air) it has one volume/density. When it has something with weight sitting above it - compressing it, it has a decreased volume and increased density. It works exactly the same way with the gas layers below the gas layers above.
The above gasses weight is greater than the force of expansion of the lower gas AND it is also (ultimately) pushing back down upon it by that same expansion force derived from the container ceiling.
I'm not in this conversation for entertainment, so that's fine.
If we want to discuss laws, then let's discuss laws as they've been established, not just your own summary.
I edited my comment, as I reread newton's third law.
Nor evidently learning anything, sadly. You have no requirement to learn about or acknowledge the natural laws that are manifestly evident in the world around you - they endure without your consent or acknowledgement.
It seems when a new one comes to your attention that you don't like, you stick your fingers in your ears and scream instead of earnestly evaluate it. This is not a good way to learn anything, nor to discuss and exchange views with others.
We are, but you don't want to acknowledge the particular law (uncontested for at least 3 centuries) we are discussing. So be it. Shut your eyes, cover your ears, and scream to your hearts content.
Fair enough. The third law is more of a conception anyhow - i don't necessarily agree with it. The resistance to motion of matter is evident (law) though, so there is resistance to force applied (however it need not match that applied force).
Because, as I said before, I am only interested in discussing the actual laws, not your own interpretations of them.
Well, those aren't the same. In the first description, the container is doing active exertion on the gas inside. In the second, the container is merely preventing the gas from expanding further. The difference is slight, but important to consider.
Think of it like a balloon. Under a normal state, the latex is merely preventing the gas from escaping by maintaining shape. However, if I were to squeeze the balloon, now the container is exerting pressure (through me) on the gas inside.
Which one is occurring in our atmosphere?
The key difference is the density of gas is less, allowing it to expand upward. as well as across.
What prevents the gas at the top from expanding all the way outward?
But you can't know the laws if you don't study reality. You can only know what you read, and believe they are laws. Even in the latter case, you can't seriously be so foolish to believe that you know all laws as a result of having read a few books!
If you must think about it this way, and it helps, then although it is untrue - go ahead! Consider "my law" to be brand new, established only by me, and in no books. It is being published right here and right now, in this conversation. How can you possibly be sure that the law is incorrect, especially considering that you utterly fail to find any fault in it and cannot provide any measurement (your own or anyone esles) which contradicts it? Please attempt to answer this rhetorical question if you can.
They are two views of the same thing, and are certainly not mutually exclusive. You can conceptualize and model either or both of them and still be consistent with what we observe. Useful is not the same as correct!
True, but surely this does not preclude the pressure the gas itself exerts in trying to expand the confines of the balloon.
Wether you conceptualize the walls to be causing the pressure, the gas within, or a combination of both makes little difference. Surely you have encountered this newtonian relativism before? Centripetal vs centrifugal?
The gas has no trouble expanding at any density, nor greater ease at a lower density. Its expansion is merely a property of that state of matter - regardless of its density.
The container walls! I expect you mean - "what prevents the gas from expanding and diffusing isotropically through the entire container" and although there are many answers and potential frameworks/conceptualizations to answer that, the core answer is the weight of the gas itself.
The gas sits on the gas beneath it (all of that gas attempting to expand), which is what causes the gradient. The weight of the gas ultimately exceeds the expansion force.
Your anonymous statement is not law.
But wouldn't that require the particles to be at rest, for their weight to affect objects (other particles) below?
Well, yeah because we're discussing the pressure of the gas against the walls.
In a rigid glass jar, there is no active pressure being pushed on the gas from the jar because the jar is rigid. It's only the pressure that the gas exerts on the container.
Precisely! So it never comes to rest. As I've been saying.
Then why can't you or anyone else establish that empirically (i.e. scientifically)? Purely coincidence?
Not really, no - but you can conceptualize it that way and everything works. Gas behaves as a fluid. Do fluids ever stop moving (brownian motion, thermal variance, atomic vibration, valence orbits etc. etc.)? Do fluids rest and have weight?
It's newtonian relativism. You may soundly conceptualize either, and or both forces as newtons third law requires you to.
My whole point is I have no desire to give weight to an anonymous someone's bare statement that has no supporting data and consider it to be a law.
Ah, so the gas is exerting pressure trying to expand the confines! Precisely.
So, we're back to a model where, logically, the pressure should be equal throughout the balloon, as the gas is working to expand outward
Not relevant here, actually! These are rotational forces. We're talking about air in a container.
But it's not sitting. It's expanding
How about many hundreds (likely thousands) of non-anonymous statements and all the supporting data in the world coupled with none which contradicts it? That's the case here.
You can continue to refuse to research/read and doubt the former all you like, but the latter is undeniable. You cannot measure or find anyone who has measured anything to contradict the law. That's what makes it a law (and no other reason; publishing, anonymity of author, etc do not factor in in any way)
If gas itself had no weight, indeed that might be the case. Because the gas has weight, and that weight exceeds the expansion force of the gas - it isn't. In imagination all things are possible - not reality.
It's an analogy... It is conceptualizing/modeling the same phenomenon from 2 different angles/directions. In this regard, what we are talking about is virtually identical. You can conceive of the gas applying the force (of pressure) outwards or the walls applying it inwards and either (or a combination of both) will work fine. As long as you are consistent, it doesn't matter - your equations will work and apply to what we observe.
The reason the law is that the gas pressure is derived from the container walls is because there are no measurements of gas pressure without such a container and there are only measurements of pressure inside a container. Indeed, the entire concept of "pressure" is nonsensical without such a container. Gas expansion (indeed, any motion) without a container, at best, would/could be called wind.
Until it cannot anymore! It is prevented from expanding more by the confines of the container and the weight of the gas itself. Gas reaches rest too - or if you prefer, equilibrium.
It continues to try to expand, as that is gas' nature.
Then what you have written is not the law. Thank you for admitting as much. If we want to discuss the property of gasses, let's speak on the explicit laws of behavior. Not just your own words.
So the ceiling itself of the container holding our air in is exerting pressure on the gasses in our atmosphere?
There was another law you had summarized earlier:
It's the basic idea of kinetic molecular theory, that gas molecules are in a constant state of rapid motion to fill the container that they are in. Doesn't the idea that in a container the gas has a lower pressure at the top of the container go against this?
https://www.westfield.ma.edu/personalpages/cmasi/gen_chem1/Gases/KMT/kmt.htm
Then you should have no trouble finding/obtaining measurement which contradicts it. Yet you can't... Why do you think that is? Could it possibly be because it IS a law, and you are wrong?
That is certainly one way to conceptualize it. Another - equally valid - is that the pressure is from the gas itself, and the ceiling (all walls of the container, actually) prevents that pressure from dissipating to nothing.
That is a fine conceptual framework, but there are others too! Because such motion is averaged over the entire gas volume, you most often don't need to consider it all. Gas largely behaves as a fluid, and fluid laws most often apply. In any case, nothing ever completely stops moving (no matter the state/phase of the matter), unless all thermal energy is gone...
No, because the number of gas molecules (in the same given area) at the top of the container is lesser. Thus lesser collisions, thus lesser pressure. As i said, it is a perfectly sound conceptual framework. It's just not necessarily correct! Being useful isn't the same as being correct, and this is most often misunderstood.