Second Law of Thermodynamics and entropy | Biology | Khan Academy

Second Law of Thermodynamics and entropy: the entropy of the universe constantly increases.

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[c.y.]

The second Law of Thermodynamics is: You do not talk about Thermodynamics.

[sigirigorilla]

i am dissipating, in to the Universe...

[ksmrafi]

" And so you're going to have more states, so higher entropy, higher higher higher entropy "

[puduhari]

Why didnt I watch this one first - spent an hour watching other videos w/o understanding. This makes total sense. Thanks Sal.

[kimfretzietunod]

so if you're thinking that you haven't changed at all. think about entropy. you are not who you are yesterday or just a minute ago or even a second ago.

[MrFTW]

I thought this topic was involved only w/ engines under the studies of chemistry and engineering. Now that it's also explained in biology boggles my mind!

[jackiechan]

Thanks for helping debunk space .. space defies 2 natural laws
2nd law of thermodynamics (entropy in gas)
Boyles law (gas pressure requires a container) also see every definition of gas pressure

Ya can only save space bu demonstrating how has can defy both these laws .... good luck!

[cactusy]

It always makes me wonder since I was in college in the class, relating to this last sentence : if everything is constantly increases the entropy of the universe, does that mean the universe is explanding and eventually explode?

[modelo]

How exactly a closed system can indefinitely increase it's entropy considering that:
1 - The system do not exchange heat with anithing beyond it's bouders;
2- The system don't do or recive work;
3- The number of particles within this system will remain constant indefinitely;
4- The amount of space wich the system occupies will will remain constant indefinitely;
5- The temperature of the system will remain constant indefinitely.

[AnindyaMahajan]

sal, the prime example of a polymath!

[virgotariq]

can you tell me that what are the applications of thermodynamics and role of thermodynamics parameters to predict thermometer reactions?? plzz help me

[yavoratanasov]

Just A question:

After the six particles moved some time and made high entropy (2nd picture of the container), at some point while they are moving they can rearrange similarly like the start positions (with little less entropy).

This is like playing pool - depending on the positions and speeds the balls can get in close to each other in small region of the pool table.

Which means the entropy of the container goes from higher to lower.

The law says 'The entropy only goes higher' - which is violated here.

How will you explain this?

[edsmith]

I've heard it described as all mass tends toward equilibrium or maximum entropy. That takes care of the infinitesimally small probability that all six of the atoms in the isolated system would gather back in the same corner. But digressing- I wonder how the 2nd law squares with the understood fact that the universe is expanding at an increasing rate. Seems a violation is taking place as all matter, instead of tending toward stasis, is increasing in speed thus energy. The six atoms in the isolated system will likely slow down in gradations as they work toward equilibrium. Why is the universe speeding up?

[shadowthehedghog]

is a fully charged battery without the use, is it a good example of a closed system? since energy is stored inside could it interact with the universe naturally?

[abdelrahmangamalmahdy]

But, I think the second law of thermodynamics only applies to random systems. For instance, if you have a strong gravitational forces or some kind of bonding, you wouldn't have that much degrees of freedom, take solids as an example.

The concept of entropy is basically derived from studying the most probable configuration of a system calling it "the highest entropy". However, if the system isn't completely random the most probable configuration wouldn't be "the simplest".

That said, the universe may stay as it is if there is gravitational balance in any point in time where gravity cancels out dark energy!

[gooddeedsleadto]

Is it important to know what percentage of energy supplied to a system has become disordered?
Entropy refers to the useless part of the total energy supplied to the system?
The energy of automobile exhaust is entropy?
Why is it important to know the change in entropy when designing a
Heat engines or chemical reactions?
Is enthalpy equal to energy supplied to the system minus change in entropy minus work?
Please answer these questions as it may tell us about the usefulness of entropy and enthalpy.
Thanks

[remy_]

So the more space there is for molecules the more entropy?

[ryanw]

By definition, empiricism requires observation, and since the observable universe is an open system, the second law of thermodynamics is rather irrelevant from an empirical point of view. Indeed, given the size difference between quarks and the observable universe--it would make more sense to assume the universe is infinite rather than not.

[hwudin]

4:12 makes no sense. How did we determien the state on the right has higher entropy? How are there more "possibe states"?

[timhatch]

Hi. what program do you use to make this video? Really well done.