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Anon questions physics (sh.itjust.works)
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[-] sxan@midwest.social 155 points 2 months ago

The water thought you were so stupid, it left.

[-] OwlPaste@lemmy.world 14 points 2 months ago

Only scientifically correct answer :D

[-] finitebanjo@lemmy.world 71 points 2 months ago

Each individual molecule did reach an excited state and entered the air, as the air molecules themselves are already highly excited. Also, if the air already has enough moisture then the moisture molecules in the air can accumulate on surfaces that are cold enough that they lose their excited state energy, and a puddle could remain even in warm temperatures because as water leaves the puddle more can also accumulate there.

[-] RegalPotoo@lemmy.world 56 points 2 months ago

Also diffusion and vapor pressure and latent heat - reality is messy

[-] thefartographer@lemm.ee 22 points 2 months ago

Someone needs to clean up this fucking sim, the rules make no sense

[-] taiyang@lemmy.world 22 points 2 months ago

Spaghetti code, unfortunately. Apt, given we boil salted water to cook spaghetti.

[-] RegalPotoo@lemmy.world 4 points 2 months ago

This game has far too many mechanics. The dev team should prune it back to the essentials and focus on polish rather than getting over ambitious and not executing anything well

[-] Aceticon@lemmy.world 2 points 2 months ago

Clearly most of the development went into highly detailed graphics so some compromises had to be made on simulation rules and gameplay.

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[-] Aceticon@lemmy.world 64 points 2 months ago

Hence why there's "boiling" and there's "evaporating" - two things that aren't the same hence two different words.

[-] Gullible@sh.itjust.works 51 points 2 months ago

>go into grocery store
>find both sexy and repulsive people

What the hell, since when have people been ahomogenous?

[-] Zagorath@aussie.zone 24 points 2 months ago

Hey, who are you calling gay‽

[-] thefartographer@lemm.ee 13 points 2 months ago

Some genius

[-] Dasus@lemmy.world 19 points 2 months ago

ahomogenous

You mean heterogeneous, lol.

[-] Gullible@sh.itjust.works 9 points 2 months ago

Apologies, I meant to write “contrahomogenous”

[-] SorteKanin@feddit.dk 47 points 2 months ago

My chemistry teacher once explained it to me like below. Does anyone know how much truth there is to this explanation?

Temperature as measured by a thermometer or your finger is an average. Not every single molecule has the same temperature. The molecules constantly bounce around, smashing into each other, transferring heat to each other. By chance, some molecules will get hit in just the right way by other molecules to reach a very high temperature and then it evaporates. So there is constantly a gradient of temperatures among the molecules and the ones with the highest temperature are the ones evaporating, until there is no liquid left at all.

As the average temperature increases, the chance of some molecules reaching a high enough temperature also increases, so warm water evaporates faster than cold water.

This also explains why evaporation cools down (like when you sweat): the molecules with the highest temperature are the ones evaporating, so the average temperature decreases as those high-temperature molecules leave the system. Only the relatively colder molecules are left behind - thus it cools as a whole.

[-] dwindling7373@feddit.it 40 points 2 months ago* (last edited 2 months ago)

I think it's much easier and truthful to stop talking about temperature and introduce speed in that context.

The average speed is what we percieve as temperature, but single molecules can be fast, so fast as to break the boundaries of the liquid pool and shoot up toward space.

Single unbounded molecules are what gas is.

[-] SorteKanin@feddit.dk 6 points 2 months ago* (last edited 2 months ago)

But temperature is not just the speed of a molecule right? Isn't it also like the "energy" stored in the molecule, or its "wiggling" or something? Like a molecule moving very fast through space can still be at a very low temperature, right?

[-] thebestaquaman@lemmy.world 11 points 2 months ago

What you're thinking about is the relation between energy, temperature, and heat capacity. When you add energy to a system (e.g. heat) the amount of energy you need to heat it up a certain amount is described by its heat capacity. If your molecules can "wiggle" (i.e. they're multi-atomic) a portion of the energy you're adding will go to increasing the "wiggling" rather than the mean speed of the molecules.

What we perceive as temperature is related to the mean speed of the molecules, so because molecules that can "wiggle" more will require more heat to see the same increase in mean speed as non-wiggling molecules (because some of the heat is going to increasing the wiggling) they have higher heat capacity.

It should also be mentioned that even the concept of temperature is really a statistical concept, so it doesn't really make much sense to talk about the temperature of a single isolated molecule, or even a pair of them. Temperature as a concept starts to be fruitful to talk about in the thermodynamic limit which classically means "a whole shitload of molecules", but (relatively) recent research suggests "a whole shitload" can be as little as 10-30 molecules. Once you go below the thermodynamic limit, we're not really talking about the temperature of a system, but it's energy, which is still well defined (although definitions may vary depending on context). Depending on who you ask, it can make sense to define a temperature also for single-particle systems, but at that point we're talking about applying thermodynamic definitions that work (and are correct in the macroscopic limit) and no longer about what we classically perceive as temperature.

[-] SorteKanin@feddit.dk 3 points 2 months ago

Thanks, that's useful!

[-] dwindling7373@feddit.it 7 points 2 months ago* (last edited 2 months ago)

Wait it's all models? Always has been.

It's kinetic energy, temperature itself is not a real thing, you are dealing with the bonds that keep water molecules together, if you wiggle hard enought, with enough energy (so... fast enough?) you break free.

I guess another way to look at it is the cloud of elecrons getting more and more messy, so that it destabilizes the bonds...

[-] Asetru@feddit.org 6 points 2 months ago

But temperature is not just the speed of a molecule right?

It pretty much is.

Like a molecule moving very fast through space can still be at a very low temperature, right?

That very much depends on the relative speed of the molecule and you. If you're not moving in relation to the molecule, a collision between you and it won't do much. Now try being hit by it (or a bunch of them) at high or even relativistic speeds. The area of you that's hit will surely become pretty hot then.

Like, have you seen footage of asteroid impacts? Have you seen shooting stars? Those are hot. Like, non-figuratively.

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[-] BehindTheBarrier@programming.dev 9 points 2 months ago

There's a bit more to it, but it's because of this effect.

There is actually a balance between liquid and gas state, just overwhelmingly in favor of liquid when at normal temperatures. There is a ratio of molecules that will hit each other and transition to gas, and an equal amount gas hitting liquid and condensing. At least when there is a balance between the two sides, aka 100% moisture in the air. Which is not how it is most places.

Normally there is always evaporated water in the air, and anything that evaporated will be moved away in any mildy ventilated area, as you say, it leaves the system. So it never reaches a balance, which is why things dry up at lower temps as water will always evaporate and leave the system.

[-] chamomile@furry.engineer 4 points 2 months ago* (last edited 2 months ago)

@SorteKanin

This also explains why evaporation cools down (like when you sweat): the molecules with the highest temperature are the ones evaporating, so the average temperature decreases as those high-temperature molecules leave the system. Only the relatively colder molecules are left behind - thus it cools as a whole.

The main principle at work here is the enthalpy of vaporization. When matter changes state, there is an associated amount of energy that is absorbed or released - in the case of vaporization, energy must be absorbed. So when sweat forms on your skin and evaporates, it absorbs heat energy from your body in order to undergo that state change.

For water, the energy involved here is remarkably high, much higher than the energy stored by a few degrees difference in temperature. For example, if you wanted to boil off 1kg of water, it would take about 300 kJ to bring the temperature up to boiling from room temperature and over 2000 kJ to boil it all into steam.

[-] Tangentism@sh.itjust.works 42 points 2 months ago

Anon doesn't realise that his mum cleared it up. Bet they think there's fridge fairies as well!

[-] Couldbealeotard@lemmy.world 13 points 2 months ago

I used to have this magic basket. I would put dirty clothes in, and later those clothes would turn up clean

[-] sugar_in_your_tea@sh.itjust.works 1 points 2 months ago* (last edited 2 months ago)

And folded, right on the bed.

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[-] echodot@feddit.uk 32 points 2 months ago

What exactly is this idiot suggesting some sort of conspiracy to hide all the water?

Obviously the water fairies take it.

[-] julysfire@lemmy.world 3 points 2 months ago

Big Science doesn't want you to know this one simple trick.

[-] ChickenLadyLovesLife@lemmy.world 3 points 2 months ago

Bigfoot gotta drink something.

[-] Phoenicianpirate@lemm.ee 26 points 2 months ago

Some asshole needs to remind him of something called evaporation and vapor pressure...

[-] Agent641@lemmy.world 3 points 2 months ago

Triple point.

If 3people point at some spilled water, it will evaporate in a few hours

[-] Rooskie91@discuss.online 24 points 2 months ago

This is your friendly reminder that the majority of people on the Internet are children.

[-] TriflingToad@lemmy.world 6 points 2 months ago

I don't believe that, I just think the children are more vocal.

[-] eran_morad@lemmy.world 21 points 2 months ago

Homie should have paid attention in physical chemistry.

[-] absGeekNZ@lemmy.nz 3 points 2 months ago

That is one bold assumption right there.

[-] psud@aussie.zone 13 points 2 months ago

The reason being that at any temperature where a liquid can be a gas (over zero degrees Celsius at standard pressure) some of that liquid will become gas.

Over time all of the liquid will become gas

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[-] Mango@lemmy.world 11 points 2 months ago
[-] echodot@feddit.uk 4 points 2 months ago

That's not surprising. That's just how electromagnetism works

[-] Klear@lemmy.world 5 points 2 months ago

Fucking magnets.

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[-] Corno@lemm.ee 3 points 2 months ago

Vapor pressure: "Am I a joke to you?"

Jokes aside, the boiling point exists because as the temperature of the water increases, so does its vapor pressure. At the boiling point, the vapor pressure becomes equal to the atmospheric pressure (1 standard atmosphere, or 760 torr). This is the reason why water boils at lower temperatures at higher altitudes!

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this post was submitted on 17 Oct 2024
478 points (95.4% liked)

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