why is it so easy to heat a water but not cooling it ?

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Why does Pepe look more and more retarded as the years go on?

>>58478770
It's a Finnish meme. As an American you will never be able to comprehend its ingenuity.

>>58478745
Because practical cooling requires a chemical reaction, and there's limited storage for liquids -- not to mention cost. Heat is easy, it just needs a bit of electrical energy to get going.

>>58478770
because the people posting it get more and more retarded

>>58478745
Heating water is not easy as well. The heat capacity of water is 4.2KJ/Kg. Which means if you want to change the temperature of 1 gram of water you need the same amount of 4.2KJ energy. This applies for both heating and cooling

>>58478773
If you can't explain a certain subject or idea plainly, you don't know it well enough.

>>58478794
See >>58478793

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>>58478785
>chemical reaction
how the fuck do you think your refrigerator works?

>>58478745
because heat can be spontaneously created from other forms of energy, but you can't spontaneously "create cold".
you have to use more energy to push the heat of something to somewhere else.

>>58478785
Pretty much this in most cases.

There are other mechanisms that produce heat (duh) or lower temperatures, albeit irrelevant when talking about devices designed for the average consumer.

>>58478793
Correct

>>58478785
>Because practical cooling requires a chemical reaction
Go back to school. None of the machines that cools things down use a "chemical reaction", refridgerators don't, freezers don't and even those lab freezers that freezes things down to near absolute zero do (because we can cool things down way past the point they chemically react with eachother)

It's actually quite easy. Just vapourise the liquid. As a vapour the liquid loses energy far quicker, thus making it cooler. This was how liquid gasses are made.

>>58478783
>pepe is Finnish
You're retarded anon

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>>58478940
Pepe isn't, but Apu Apustaja is.
Who's the retard now?

>>58478951
FINNS DON'T MIX PEPE AND SPURDO REEEEEEE

>>58478745
Because combustible matter is more accessible to us than matter that can be easily made to react in an endothermic reaction. Thankfully, the vapor-compression cycle solves that problem.

>>58478926
>what do you need to have in order to easily change states from liquid to vapor and back again

>>58479018
Fuck tons of energy.

>>58478745
How so?

Cooling water is exactly as easy as it is heating it.

>>58479018
A phase change. Which happens due to difference in temperature and/or pressure. NEVER a chemical reaction unless the chemical you add to react with it causes a endothermic or exothermic reaction. But the phase change is STILL due to the change in temperature and not the chemical reaction.

>>58479028
In a literal sense yes, in a practical sense no. It takes the same amount of energy but taking energy from water is much harder to accomplish than putting it in.

>>58479050
Freon is a chemical that does not freeze during the phase changes and temperatures in a refrigerator system. But there is nothing special about freon apart from that, you could put water or many other things. The only thing making it cool is the pump which requires energy.

>>58479056
Fuck, looks like I do need to go back to school. I made straight A's all the way up to my senior year, but my education obviously means nothing when I can't even remember the most basic and simple shit.

>>58479085
Don't worry about it, there is certain nuances in the terms used. I likely would not know that if I did not have tons of chemistry and physics classes in university.

I don't think they usually teach what a chemical reaction really is. A common sense understanding of the term is that it's when a chemical react to any external factor including temperature, pressure and so on. But a chemical reaction only means that two chemicals react with each other.

>>58479105
>I don't think they usually teach what a chemical reaction really is.
"A chemical reaction is permanent and cannot be undone, anything else is a physical change and not a reaction"
Not the other anon but that's the rule of thumb I was taught back in like 3rd grade.

>>58479105
Thanks, makes me feel a bit better. I do need to get my ass in community college regardless lol

>>58479068
Again, how so?

Taking energy from water is exactly as easy as putting it in. What makes you think otherwise?

>>58479121
Well... That is true. But might be confusing.

Although "permanent" should be better defined because it is not really permanent because you can often make another chemical reaction to remove one (or more) part(s) of the initial reaction.

But my definition "when two chemicals react with each other" is not good either. For example salt water is not a reaction with salt and water. It is only a solution. It can be separated with boiling it, but you don't need a chemical reaction to separate them at least.

>>58479153
Do you not understand what "practically" means? As a human with normal capabilities and lack of fancy shit like peltier devices, it is far easier for you to add heat to something than to take it away because there's tons of ways you personally can put energy into something but taking the energy back out past a certain point becomes incredibly difficult. The thing is, the plateau of energy removal is far lower than the one for energy addition.


I can very easily turn water into steam by rubbing two sticks together and making a fire. If I've captured the steam I can easily turn it back into water by moving it away from the fire due to its melting points and such. But I have no good way of turning that water into ice without access to electricity and modern technology or the off chance it's winter and below freezing out.

>>58478770
/int/ is where most new memes come from

>>58479121
I'm autistic and have a hard time accepting absolutes, so don't take my conjecture too seriously... I've always thought that microscopic detailed dynamics of particles and fields were time-reversible, because microscopic equations of motion are symmetric with respect to inversion in time? It's to do with T-symmetry, if I'm not mistaken. (Can't be bothered validate my info, as I'm on mobile and detest this area of gruellingly boring mathematics.)

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>>58479341
Anon I went to the "farm kid" highschool and a community college and I'm blue collar. I have no clue what the fuck you're on about.

>>58479414
In basic terms: If we humans were a godlike race with astonishingly high intelligence and equipped with the means to develop technology that shits all over anything Star Wars can dream up... it would be possible for us to reverse chemical reactions by observing and manipulating particles on the quantum level, aka reversing time itself (locally).

>>58479531
Oh. Well sure if you can do that kind of crazy shit then most laws applying to matter go out the window.

>>58479543
That is incorrect. We have the laws of physics and we have to abide by them. Most rules can be bent, sure, but a rule is not a rule if can be invalidated through mathematical and/or technological means.

>>58479179
Chemical reaction is an exchange of atoms between molecules using electromagnetic force.

>>58478745
Difference of heating and cooling on an example of an electric kettle:
In a kettle you have a highly resistant wire usually made of tungsten. The wire is located at the bottom of the kettle. Electricity passes in the wire and because of high resistance the wire heats up and the wire heats up the water. The hotter water rises up and mixes with colder water. It is an almost direct conversion of electrical energy into mechanical energy (heat).
If you want to build some sort of anti-kettle you can't directly apply electric energy like in the case of heating. That's because you need to transport energy away from water, not to add energy like in case of heating. You need a cooling element to take the heat from the water and transport it to radiator to dissipate it there. It is usually done by circulating Freon between the cooling element and the radiator using a pump. Also it would be nice to place the cooling element on top of the anti-kettle so the water will mix naturally like in the case of heating. But you can't do that because in that case you need the anti-kettle to be full all the time. So you put the cooling element at the bottom and add a mixer to mix the water mechanically. In the end you get something like this: https://www.youtube.com/watch?v=AxUPPrKbAyM
That system is much more complicated than just a tungsten wire like in a normal kettle.

>>58479341
>>58479531
>>58479625
You're taking all this shit way too literally. Your argument comes down to how the phrasing was worded.

I don't claim to be an expert in physics or anything, but your explanation sounds like complete hogwash. Doesn't even fucking make sense. Go outside or something.

>>58479531
Time only have one direction, there is no evidence to support a claim that it is possible to reverse time in particles or anything.


>>58479701
>Chemical reaction is an exchange of atoms between molecules using electromagnetic force.

Yes, that is absolutely correct and a good definition. But completely meaningless in normal everyday use.

>>58479701
tl;dr for this:
In case of heating you take energy out of wall socket and ADD it to your kettle-water system. In case of cooling you take the energy out of the wall socket and need to use it to SUBTRACT energy from your anti-kettle-water system. I.e. you need to use a positive amount of energy to create a negative amount of energy in the anti-kettle-water system. That's why the shit is more complicated.

>>58479341
>>58479531
>>58479625
Yeah, you don't have any idea what you're talking about. Grab a book on QFT, or if that's "gruellingly" boring to you then just shut the fuck up about it and go back to ricing your desktop or something more appropriate to your limited intellect.

>>58478793
No, this is not true. The specific heat capacity is the energy required to _heat_ the water by 1°C. To cool it by 1°, you need to 'extract' 4.18kJ from the water. This can be done passively and requires no energy input at all.

>>58479937
I never said you have to extract heat off water. Re read my post.

>>58479814
I've been thinking about the concept of time lately.
Time is often considered a kind of 4th dimension that acts differently that the others in that it only marches forward and it's not realistically possible for objects with mass to move freely in any direction.

Yet there exist paradoxes that suggest time does not influence the validity of math and statistic. My favorite example of this is the 2 goats 3 doors thinking experiment. Where the action of opening one door influences the probability of the remaining doors, despite the fact that the rules of time would suggest this impossible.

I like to think of it like a comparison between the 3d realm we live in and what it would be like if we could create life that existed only on a 2d plane, such as a piece of paper. This being would never be able to fathom a 3rd dimension no matter how much you described the way it works to it, and the paper itself could still be manipulated in 3 dimensions by us.

Not to suggest there a beings manipulating extra dimensions we cannot perceive, but there may be things outside our scope of understanding that play a role in the dimensions we live in.

i mean there's not really any evidence to suggest this quantitatively but it's fun to think about.

>>58478866
>can't spontaneously "create cold"
"cold" doesn't exist

>>58478785
https://www.youtube.com/watch?v=QJjiKBjhj0I

>>58478792
This

>>58480086
Just like evil

>>58478745
Second law of thermodynamics.

>>58478770

he follows the flow of popular culture

Water is an excellent conductor of heat but air is not a great conductor of heat. That's pretty much it. "Cooling" is the act of heat transference.

>>58478745
Because heat always goes from hotter to colder bodies. To cool water there needs to be a working body(gas) that has dependencies between temperature, pressure and volume. By expanding gas we make it cooler, then heat it up by contact with water, then move it somewhere else and compress it, effectively heating it above room temperature, then cooling it down by the contact with the room. Rinse and repeat.

>>58478793
Think you mean 4.2J for 1g

>>58479121
That's like saying a ball rolling down a hill is permanent and cannot be undone without putting in physical work to undo the will of the universe to enter the lowest entropy state

>>58480034
>in that it only marches forward
What makes you think time “moves” forwards?

That's like saying everything behind you doesn't exist yet, just because you can only see in one direction. It's the same logic people use to infer that the future does not exist yet, simply because they can only see the past.

Makes no sense to me. The flow of time is an illusion created by your brain.

>>58480034
>Yet there exist paradoxes that suggest time does not influence the validity of math and statistic. My favorite example of this is the 2 goats 3 doors thinking experiment. Where the action of opening one door influences the probability of the remaining doors, despite the fact that the rules of time would suggest this impossible.
Good job, you completely failed to understand this experiment.

Time has fuck all to do with it, it's just a game of information and information exchange.

>>58480144
/thread

>>58480332
>lowest entropy state
energy*

>>58480361
Sorry I should have said "objects with mass march forward in time in one direction."

>>58480370
The goats and prize are placed behind the doors and do not change places. When you choose a door you have a 1 in 3 chance of picking the prize. When you have a goat revealed to you, the statistical chance of the door you did not pick changes at that time despite previous chance. It's a paradox because the laws of mathematics retroactively supersede previous chance.

>>58479937
It can only be done passively if the energy can be transferred to other, less warm particles.

>>58480361
>The flow of time is an illusion created by your brain.
>in 2017
Have you been living under a rock? It's already been scientifically proven that time flows differently in different parts of space.

>>58480609
>It's already been scientifically proven that time flows differently in different parts of space.

Only when we observe it.

>>58480768
WHY DO HUMANS AFFECT THIS ?! WOULD IT WORK WITH BIRDS ?!

>>58480609
“If I move slightly left, I see a slightly difference picture of this room! Clearly, my moving left warps the room itself, rather than just changing my point of view of a static room”

>>58480462
>The goats and prize are placed behind the doors and do not change places. When you choose a door you have a 1 in 3 chance of picking the prize. When you have a goat revealed to you, the statistical chance of the door you did not pick changes at that time despite previous chance. It's a paradox because the laws of mathematics retroactively supersede previous chance.
It's a paradox because you don't understand it

>>58478969
They do now

>>58480768
No.
>>58480609
Are you referring to relativistic slowdown of time due to gravity?

>>58480308
You are retarded
>4.2kJ/kg
>4.2J/g
They're equivalent

>>58480931
Gravity is just lag in the simulation. When there's too much mass in one place, the supercomputer has a hard time rendering it all smoothly. God/our reptilian overlord needs to build a faster computer.

>>58480034
>Where the action of opening one door influences the probability of the remaining doors, despite the fact that the rules of time would suggest this impossible.

That has nothing to do with time. It us just that each choice is a different question. One question has (2/3) chance to get a goat and the second question has (1/2) chance to get a goat. Time is not a parameter in this at all.

Other dimensions beyond time and with different directions of time is considered in physics. For example the 5th dimension is a dimension of infinite 4dimensional instances that branch out at every point in time. These things (and 6 more dimensions) are used as a basis for M-theory and string theory. But there is no evidence that such a thing actually exist, it is just something made up to explain some potential math.

>>58480975
Why don't you just say 1 calorie? instead?

>>58480462
The paradox is probably easier to understand if you think of 100 doors with 99 goats. After you've picked a door, 98 doors with goats are opened. Do you still stick with the 1% chance of winning or choose the door that doesn't have a goat with 99% probability.

>>58478783
I'd just like to say, after years of browsing /int/ and /pol/, that Finns are a bunch of very unfunny circlejerkers. each and every one of their (or "their") memes are retarded and forced. it's 9gag: the country.

>>58480034
>>58481157
Monty hall is about as much of a paradox as me telling you “the die landed on an even face” is a paradox because it makes 2,4,6 have a higher chance of winning...