Second Law of Thermodynamics - Sixty Symbols
ฝัง
- เผยแพร่เมื่อ 16 ม.ค. 2017
- Professor Mike Merrifield discusses aspects of the Second Law of Thermodynamics. Referencing the work of Kelvin and Clausius, among others!
Professor Merrifield is the Head of the School of Physics and Astronomy at the University of Nottingham.
Gamma Trilogy: • Gamma Trilogy - Sixty ...
Patreon: / sixtysymbols
Visit our website at www.sixtysymbols.com/
We're on Facebook at / sixtysymbols
And Twitter at / sixtysymbols
This project features scientists from The University of Nottingham
bit.ly/NottsPhysics
Patreon: / sixtysymbols
Sixty Symbols videos by Brady Haran
www.bradyharanblog.com
Email list: eepurl.com/YdjL9 - วิทยาศาสตร์และเทคโนโลยี
![[TH] VCT Masters Shanghai Playoffs DAY 3 // FNC vs FUT | EDG vs PRX](http://i.ytimg.com/vi/pw2T5v0ogDI/mqdefault.jpg)
"In this house we obey the laws of THERMODYNAMICS!"
I saw what you did there!
It just keeps going faster and faster.
You know, I just realized that probably explains why the Simpsons are able to afford multiple mortgages on such a large, 4 bedroom house with 3 living areas (rec room, living room and the mysterious rumpus room), 2 cars and who knows how many whacky adventures, despite only Homer working in the house and according to the bear tax episode, he only makes 3 figures on his paychecks. Lisa must have solved the energy crisis.
“Lisaaaaaa!!”
but.. but.. my perpetual motion machine!?
Four perpetual motion enthusiasts disliked this.
... one day we 'll make a fortune.. you just wait and see! ;-)
you can already make a fortune selling perpetual motion to the gullible.
Or EM drives... just sayin'. ;-)
One of them was Trump for sure
Perpetual motion enthusiasts? Who isn't?
Personally I'm a big fan of invisibility hats and seven league boots, and the fact that I know they don't exist or ever could, does not cool my enthusiasm!
I dislike this video for quite different reasons: It's much too superficial!
This is the best description of the 4 laws of Thermodynamics I have ever heard
4?
If u count the "0th" law, there r 4 alltogether.
Yeah, the proof of the equivalence of Kelvin's and Clausius's versions of the Second Law is so clear, much better than you usually find in the textbooks.
Saeed Baig 4 law? can u tell what law sepertatly describe with few words?
Really?
I actually think that the way the 2nd law explained in this video is kinda confusing.
Basically it's saying in a closed system, "work in > work out"...
0th law: There's a game
1st law: You cannot win
2nd law: You cannot really tie either
3rd law: You have to keep playing
The Guy That makes you mad I learned this as, "you have to play the game (first law), you can't win (second law), you can tie at absolute zero (third law), but you can't reach absolute zero." Not sure what the last bit was from, there is always some quantum tunneling which involves some motion and thus some heat or something Physical chemistry is where you learn to like synthesis because math gives you a headache.
I like the nail and gear there.
Joshua Hillerup hard as nails
That's the icon for the Hello Internet podcast
The Guy That makes you mad yup :)
I liked the stirling engine
5:53
First law of Thermodynamics: Don't talk about thermodynamics.
Ocean Bagel Bravo
bravo
Only applies if you're not an engineer
Sometimes explaining the obvious makes it confusing and not so obvious.
Mind blown!
The 2nd law of thermodynamics is like the theories of Relativity. Seems reasonably easy to understand (bit it's not) and leads to loads of mind-blowing consequences ! Brilliant from Professor M again ! Ty!
At 3:10, when Prof M. says "if you're prepared to inject some energy, you can make hot things colder and cold things hotter", I'm sure he really meant to say "... hot things hotter and cold things colder".
Phil P Yes, it seems obvious that Prof. M. misspoke at this point. The video should be fixed to avoid confusing people.
Mark Holm Too late now. Conspiratards will just twist whatever is done to prove their point! (which is conveniently located at the top of their head btw) People born in Ignoramustan learn from childhood that even slips of the tongue can be convoluted into virtually any moronic claim.
Charlie Franz Well, Ron Burgundy could probably think of something to say about that.
That statement is still true for the 'cold things hotter part'.
Actually, there are no mistakes in the first statement at all, physically talking, of course.
I see your Channel for like 5 years, it is the best!
I don't know what I was doing all this while with teachers who are so obsessed with exams that they forget that the subject needs to be at the center . Excellent explanation and fun too.
This was a really great video Brady! I'm glad I watched it. Hope you have a fantastic day. : )
Great video, very clear in argumentation which cannot be taken for granted at this topic! Will there be a second part where Mike explains the connection of these two statements to the notions of probability, entropy and information? Please ;)
This law is clearly the most important thing in the universe since this is the one reason time can not flow backwards.
No time machines, at least not to the past
No one can put Humpty Dumpty back together again.
That was really cool! I did not expect this law equivalence ^^
excellent demonstration of logical deduction & a great explanation of one of the golden laws! TY
Thank you Professor and Brady. Your videos are great
*The 2nd Law*, nice album
This is a superb explanation of this idea.
I wish I had him for a teacher. He makes the subject easily understandable.
Zeroth Law of Thermodynamics was invented by Captain Obvious.
There's no reason to assume transitivity. Indeed, plenty of things in the real world aren't transitive.
Okay, now I'm interested. Could you give me an example to show what type of things aren't transitive please? I love learning new things. :3
for science it has to be stated even though it's obvious
Well abstractly the notion of friendship is non-transitive. That is to say, if Alice is friends with Bob and Bob is friends with Charlie, there's no reason to assume Alice is friends with Charlie. More concretely we could think of chemical reactions, say. If chemical A reacts with chemical B and chemical B reacts with chemical C, there's no reason to assume that chemical A will react with chemical C.
oooooh this kind of thing. Yes, that makes sense. Thank you! :)
Simply Brilliant!!!! I love it when you guys write out the equations and stuff.
Equations? What Equations?
you seriously didn't watch the video... 5:57
in plain sight W=q2-q1
fantastic description of thermo! thanks
That was an amazing explanation!
I really enjoyed this, it defined thermodynamics more specifically for me. I always understood it, but I think I needed this to be able to explain it to other people and understand it more intuitively.
Yeahhhh baby yeaaaaah! Oh behave!!
Great explanation,amazed!
love your videos please keep the science coming!
That was really interesting.
Thanks!
Nice one!
Cool video, love this channel!
lol, thank you Brady i actually needed that
solid upload
Nice! Please make a video on the laws of thermodynamics in relation to quantum mechanics, entanglement and negative enthropy.
Could you do an update video on one of your side channels with Prof. Moriarty?
Does the third law of thermodynamics mean if I keep the kitchen at absolute zero, I'll never have to tidy it up?
I assure you, it will always be easier to tidy up the kitchen than bring it to such low temperatures. Also, as you may already know, leaving the fridge door open will heat up the kitchen, not cool it. So your fridge will not be cleaning your kitchen any time soon. :-)
foxpup
Of course I meant to say, would bringing the temperature of my kitchen to within a pubic hair (blond one - correct technical term) of 0K slow entropy enough to effect the washing up?
I'd say "washing up" along with "order" is a subjective concept anyway. The observer determines what it means for the kitchen to be "washed up". Since you would be the observer here, its your call. :-) The kitchen will take whatever form it has and the observer will create its own assessment of the kitchen's state based on personal objectives and bias. :-)
foxpup
Aaargh! I'm all 'washed up' and on an express entropy elevator to disorder.
foxpup
PS There is nothing subjective about that pile of washing up.
Another science question; why do cornflakes require a high speed angle grinder to remove them from the bowl after 12 hours curing time?
I also like how the first example just turned the whole box into a perpetual motion machine.
nice vid thanks for this, another with going into more detail about the 3rd law would be nice to see in this format (a simple calculation/demonstration for entropy would be salt in water freezing at lower temperature, or go back to fridges)
Great Video
in my uni they say: the third law of thermodynamics is that you will write the thermodynamics exam at least twice
This is amazing.
I was very much fascinated by these thaught arguments during my physics bachelor's, even if thermodynamics was the one course that took me three times to pass it.
Cold flows from a cold body to a hot body.
schitlipz either you're an idiot or you're joking.
Nope. I actually argued that and got a piece of skin for it. :D It's just perspective. Similar to electronics when you switch from conventional current to electron current. What matters is potential.
Mathematically, it is equivalent, but physically it is very defined which one actually happens. We are quite certain that it is in fact the electrons that flow (even thought the positive flow is the one that became popular in engineering) and we are fairly certain that it is the heat energy that flows.
But as long as you only want to calculate stuff within that model, you are allowed to switch from heat flow to cold flow any time you like, even though it does not have any practical use.
Our perception of which of two opposites is the "real deal" matters. Like in the case of matter-energy itself - is it as important as the "empty space" around it? No. It's about how nature behaves with respect to itself. Having the notion that one thing is _the thing_ and the other not is biased and confines thought. The practicality of it may seem trivial, but I believe it is not.
Well, sure. You *are* just doing a coordinate transformation after all...
Finally, the law's true essence!!!!!!!!! The disorder is breaking my system.
Also a neat exercise in proof by contradiction! (I.e. [P true ---> Q true] is the same as [Q false ---> P false])
Very interesting way to prove something.
Excellent!
I see what you did there. Using the HI logo with the gear and nail for your engine. ;)
I thought it was a nice touch.
We need more physics on Sixty Symbols. Why there is not much uploads the past year?
So, Maxwell's demon, or a mechanical equivalent, cannot exist in the real world.
IF the 2nd law of thermodynamics holds true in reality. There are a few quantum models that blur the lines a bit I believe. I am an amateur and could easily misinterpreted the paper.
In a closed system yes. There's a slight get around which is that the demon would have to be powered by something in the same way you can get around this by plugging a fridge into the mains. If you have an externally powered demon then it can work because the decrease in entropy of whatever the demon's messing around with will be more than offset by whatever's powering the demon.
So what your saying is that in order for this to work you would have to power the demon with something out of this life?
No, the entropy of the system decreases, but the entropy of the system+demon+demon's environment increases, thereby saving the 2nd law of thermodynamics from being violated.
Please make another video about theoretical limit to the thermal efficiency of any heat engine, Carnot efficiency, and maybe about its applicability to fuel cells and batteries!
At the beginning is it said that there is only one definition of temperature. But since temperature is like an average of the molecules kinetic energy, wich is related to the particles' speeds... my question is if the Temperature of a particle needs relativity corrections if the particles are moving near speedlight??(like a bunch of protons in particle acelerators)... general relativity could change these conclussions of the laws of thermodynamics?
more please! =)
need a second part of this video.......
explain entropy thru 2nd law
I thought the First Law of Thermodynamics was, "Don't talk about Thermodynamics?"
lol this is great.
The associative property of the 0th law is important, when finding the mathematical limit of an infinite series. For thermodynamics, we are dealing with extremely large numbers for things like the number of gaseous molecules in a self compressing universe or star? Failure to be careful with bracketing in algebraic operations within infinite series results in silliness? I guess you could say that the smallest cardinal number is countably infinite and is nonetheless much larger than the number of particles in the universe, and in the quantum field, and dark energy?
Amazing explanations guys, it's amazing how you guys helped me during me aerospace engineering degreee many thanks!
I was pleasantly surprised to see a proof of logical equivalence. Those kinds of proofs are common in mathematics.
A nice followup video would be on theoretical upper limits (e.g. Carnot efficiency, Betz limit, etc.). They represent interesting crossovers from physics to engineering... even if they are super annoying.
Nice nail and gear engine
I love this guy.
We want more on thermodynamics!
There's never enough entropy videos 😂
Is the second law something we observed, or does it derive from some other theorem?
+Lukkas theKing
In contrast to the first law (which was initially also a purly empirical, but later got its theoretical foundation from Emmy Noether, who correlated all conservations laws in nature to symmetries in nature) is the second law only an empirical law. In contrast to common believe it is not even strictly valid, because entropy can anytime decrease, at least in theory. The likelihood of this happening is just so insanely small that the universe is by far much too young that something like this has ever happened until now and as a result we have never observed a spontaneous decrease of entropy in a closed system yet (and it's very likely that we never will). In the end entropy i just a result of having so many particles in macroscopic objects, that what we observe are just statistical effects (you may wanna google Boltzmann's statistical interpretation of entropy for a better understanding). The perceived flow of time into seemingly just one direction (although all elementary particle reactions are in principle reversible) is also just an effect with the same cause.
Frank Schneider Thanks for the explanation.
It gives it a theoretical foundation. As long as there is temporal symmetry in the Lagrangian, which turns out to be true for systems obeying the laws of thermodynamics, there is energy conservation. That's a purely theoretical statement, which doesn't require any empirical input.
transylvanian
If you refer to conservation of temporal symmetry: we know, that CPT symmetry is always conserved (at least to our current knowledge). As we know that CP-symmetry is violated by the weak force in certain processes, e.g. in some kaon or meson decays, it's obvious that also T-symmetry in these processes must be violated so the CPT symmetry is conserved. Oops
So what does this mean for the energy conservation of this process ?
Well said, but I was hoping to hear about entropy.
I like that fleece jacket! Way cool.
the brown paper is only used in numerphile videos ?
nail and gear would really be a great term to describe any "unknown or ambiguous" piece of machinery
Surprised to see a copy of the Atlas of Creation on the bookshelf.
"No energy system can produce sum useful energy in excess of the total energy put into constructing it.
This universal truth applies to all energy systems.
Energy, like time, flows from past to future."
I actually have a Thermodynamics exam the day after tomorrow, this a good way to go over my notes again!
What are the chances? ...
Doesn't this just say that in 2 examples, they can't disagree, but that there could be other examples where they do disagree? Therefore they don't have to be exactly the same?
A square and a rectangle both have 90° angles in all 4 corners. Both also have 2 pairs of opposite sides that are of equal length. Given some random polygon, if either rule is violated, then the shape is neither a square nor a rectangle. However, that doesn't mean that if both rules apply, that it's both a square and a rectangle.
Engineers say, there is also law 4 of thermodynamics: You always will have to write the exam of thermodynamics twice.
What is energy made of ? It's not made of anything, it's the aether vibrating (heat).
Second law, entropy is really the "vibration averaging"of two differing areas of the aether (work).
How about negative temperatures? Don't they make heat flow out of the object whatever the outside temperature is?
I was also amused at the presence of "The Atlas of creation" on his book shelf. It seems unlikely that a professor of physics would actually subscribe to (basically) a treatise on Muslim Creationism, but I certainly understand a man of letters having academic interest in such an artifact, as it really represents a long concerted, elaborate effort to demonstrate an unarguable position by example.
We may need a new channel... "Bookshelves of the Professors".
Professor Merrifeld, I would love a comment on this if you have a moment.
He already has. There is a video about that. The short version is: It was sent to him and he likes the pictures in it.
I love how you count in binary in the truth table :)
I always think about the zeroeth law whenever I use a thermometer. At least, one that isn't infrared. Don't think it applies to IR thermometers.
There is also the mathematician statement Carathedory's.
When the 2nd Law comes up I always think of Muse (:
The change in the entropy of the universe is always greater than or equal to zero. Nothing you ever do will result in a net decrease of the entropy of the universe.
So the video ended saying that either both statements are correct or incorrect. But they didn't say which one is the case. So are those statements correct?
Thermodynamics basically says you don't need negative numbers, but they may help if you don't want to use large exponents and quantum statistics.
I WANT THAT STIRLING ENGINE
please make a video on higgs singlet....
Can you guys discuss a BTU
And what about one of the most powerful equation in physics PV = mRT?
n
The aether has a minimum quantum vibration limit (minimum heat) , meaning an absolute zero temperature can never be reached (it's always vibrating).
What about the 4th law, Onsager Reciprocal Relations
Where can I buy these magic engines?
Atlas Of Creation on the bookshelve?
If I'm trying to produce energy to warm up a cold room I sure as heck can use that heat!
Indeed, heaters are one of the very few things that are literally 100% efficient.
Well, as humans we have an optimal operational body temperature so, in practical terms this heat is not "waste". It is if you expected your heater to be a car though.
transylvanian There is no energy that is *not* used to heat space, so in that sense a heater converts 100% of its energy into heat, as it should. But you are right that from a thermodynamical point of view this heat is considered 100% waste.
Let's encode our minds into waves that circle the shrinking universe fast enough to allow us to think an infinite number of thoughts before it collapses.
you go first
The universe is expanding.
I think that's enough weed for the day, Gordon.
At least the 26 billion LY diameter sphere of it that we can see sure seems to be expanding. :-) I personally make no statements about what is going on further out. I'm not a big fan of extrapolation. We really don't know what is going beyond that but it seems that anyone living 13 billion LY away in one direction has no idea what someone living 13 billion LY away in the other direction is doing if such people existed. They are mutually beyond the threshold of observation. :-)
What collapses? The mind, the thoughts or the universe?
Law And Disorder: Special Temperature Units
When people say convection is a method of heat transfer, Would it be wrong to disagree ?
Considering convection requires gravity. And still requires either Conduction and/or Radiation.
TheProCactus convection doesn't require gravity. It works due to motion of fluid, which can happen in absence of gravity.
And it is sane as conduction only on a microscopic scale at the interface. On a macroscopic scale, heat if flowing due to fluid at high temperature moving.
Well, the density of a fluid changes depending on how much energy it has, and it is that difference in density that gravity is acting upon. The resulting movement tends towards a fluid of equal energy distribution, so it seems fair to say that it is a method of energy transfer. I suppose it's also fair to say that the higher energy part of the fluid is touching other fluid, so conduction is certainly a factor.
TheProCactus convection works with gravity in your house because Gravity is there, but without gravity surely convection will still work because a high pressure gas would move to a lower pressure.
ok, Think of this.. What if I only have 2 atoms. Where does convection fit then.
TheProCactus convection is a macroscopic phenomenon. We don't consider individual atoms when studying it. The fluid is considered as a whole.
Fluid can flow due to external causes, like fans despite being in zero gravity. That is called forced convection.
Free convection requires gravity because it works on buoyancy.
Edit: Not so sure about this, but I believe that temperature itself is a macroscopic quantity, and doesn't apply at the atomic level
9:50=I take issue with his statement that "they're either both wrong or they're both right, which is just another way of saying that they're saying the exact same thing". The fact that their truths are correlated doesn't seem to prove that they're equivalent.
For example, theorems in maths are derived from axioms. If a necessary axiom is true, then the theorem is true. And if a necessary axiom is false, then the theorem is false. However, that does not mean that the axiom and the theorem are therefore equivalent. Isn't it possible that one of the versions of the law (either Clausius' or Kelvin's) is derived from the other?
the important nuance is that the proof is birectional, i.e., violating Kelvin is violating Clausius AND violating Clausius is violating Kelvin.
also, axioms cannot be true or false, they can be accepted or unaccepted.
more to your point, if you can prove that a violation of theorem a directly violated theorem b AND a direct violation of theorem b violates theorem a for each and every violation of the respective theorems, you prove equivalency.
Extra bits? Plz
Human has a serious misconception about energy. Energy is usually expended by using direct. However, if we use energy indirectly, it can be used without spending zero percent. This way more energy can be generated without wasting energy.
what you are talking about is perpetual motion machine.
it gets little sad. But when you think about entropy & Big Bang ,all the things,then you get excited that there is something needed to be discovered yet.
at 3:14 the prof. mixes colder and hotter. annotation?
So if I have a Glowing Red 1000 Degree KNIFE vs Glowing Blue -1000 Degree KNIFE what does Clausius have to say about that?
-1000 degree (Celsius/Fahranhiet) doesn't exist.
5:49 can we someone please explain why the amount of waste heat is equal to the amount of heat absorbed by the magic fridge.
It means waste heat is going back to input heat! Magic fridge is absorbing waste heat!
I suppose the fridge in this theory would represent a closed system.