# Introduction to entropy | Energy and enzymes | Biology | Khan Academy

## 18 thoughts on “Introduction to entropy | Energy and enzymes | Biology | Khan Academy”

1. RavenOfRed says:

First? Haha. Feel like such an idiot saying that

2. agent1672 says:

How can entropy be reversed?

3. RICHARD DAMROW says:

OMG! Is it possible that "entropy" is so easily understood? Or, is it, you are one great teacher? This is at least my 5th entropy video, but it is the first one actually understood. Look forward to your next video.

4. Dan Varlan says:

Thank you man!! a lot!!

5. CityOfSky CityOfSky says:

I came upon entropy when I was studying decision tree, which was part of the computer science. Everybody told me that entropy was about disorder, about how much information we could get from it. But seriously, I never understood what it actually meant, until I saw your video. I just cannot believe the fact that I understood it in about seven minutes! If I had seen your video earlier, I wouldn't need to struggle for a month to try to find the answer! Thank you, you are an amazing teacher!

There's only one more thing I need to know. Shannon developed the formula of entropy decades ago. We need it to calculate the information gain when we construct a decision tree. I found out that you also majored in computer science. So is there any video about how the formula was developed, how we could use the formula to calculate the information gain?

6. gambart2002 says:

the best explanation

7. Harsh Vardhan says:

The best thing about khan academy is that they explore and discover what is to be taught instead of telling us whats the discovery is , straight forwardly .

8. 64standardtrickyness says:

I'm confused as to what the number of states refers to as a human we could say that an unbroken vase has few configurations while a broken one has many however thats a purely human thinking style because there's no reason the vase couldn't break
Just to clarify an orderly stacked pile of blocks has less entropy than that of a randomly thrown pile of blocks? but why? what is the physics that says that in configurations the orderly stack must remain an orderly stack while the blocks of the randomly thrown pile do not have to maintain their relative positions? Or to be more blunt what stops an Alien race from saying that the randomly thrown pile is actually not random but a perfect RRRR shape or whatever and thus they consider only configurations of the blocks preserving the RRRR shape?

9. Nagarjuna T V says:

Can u explain second lesson molecular structure of biological system

10. vatarants says:

Is it possible to reduce entropy from the system?

11. Geon Park says:

messy != entropy
I kinda laughed here

12. Heba Ebrahem says:

Well , i can't thank you enough , before i found this video ,i have wasted like 1 hour trying to grasp Entropy meaning from other sources and i was about to drop the whole thing xD

13. Yami 2107 says:

I swear u r the best teacher ❤️

I understood more in this 7 minute video than all the chemistry classes my teacher spent teaching this concept

15. Stanislav Mudrets says:

I disagree with you when you say that a messier room doesn't have higher entroy then the cleaner room. You claim that they are just individual states. However, what you didn't consider was the fact that living organisms (like humans) have preference for some states of a system vs. other states – because of the diffirences in the consequences of having some states vs. others. Furthermore, there are fewer states that are preferred than there are of those that are not preferred. Therefore, the reason that a cleaner room has lower entropy is because the number of clean configurations is smaller than the number of messy configurations.

16. Ahmed Ismail says:

Messy or Ronaldo? Ha ha ha

17. Vaibhav R says:

I have no words. This is so well explained

18. Rowan smith says:

entropy is a measure of how much some energy is distributed over the particles?:0