The First & Zeroth Laws of Thermodynamics: Crash Course Engineering #9

In today’s episode we’ll explore thermodynamics and some of the ways it shows up in our daily lives. We’ll learn the zeroth law of thermodynamics, what it means to reach a thermal equilibrium, and define the first law of thermodynamics. We’ll also explore how stationary, adiabatic, and isochoric processes can make our lives as engineers a little easier.

Note: Different branches of engineering sometimes define the first law of thermodynamics differently, depending on how work is defined. Essentially, work released from a system might be defined as a positive value or a negative value, and thus the first law can be defined as either Q-W or Q+W. Both are acceptable forms, depending on how the system is defined! We chose to focus on only one definition here to limit the confusion.

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RESOURCES:
Çengel, Yunus A., and Michael A. Boles. Thermodynamics: An Engineering Approach. 8th ed., McGraw-Hill Education.

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[crashcourse]

Note from our Content Consultant: Different branches of engineering sometimes define the first law of thermodynamics differently, depending on how work is defined. Essentially, work released from a system might be defined as a positive value or a negative value, and thus the first law can be defined as either Q-W or Q+W. Both are acceptable forms, depending on how the system is defined! We chose to focus on only one definition here to limit the confusion.

[alexrossouw]

"The Higher you get, the more potential energy you have"

Hehe

[VarretInxve]

Enthalpy is something I’ve always struggled with during my thermodynamics classes and yet it can be explained so simply. I wish my teachers were as enthusiastic as those on Crash Course, because I feel burnt out with my mechanical engineering course at college and yet those videos do spark interest and appreciation for those topics in me. Thank you, dr. Shini and whole Crash Course crew!

[hdsiroha]

As a kid whenever I didn't want to clean my room, used to say that "entropy is the law of nature".

[Bird_Dog]

The 3 laws of thermodynamics as I understand them:
1. You can't win, you can at best break even.
2. You can only break even at 0.
3. You can't get down to 0.

Also: The 4th law of thermodynamics: "Never attempt to explain the other 3 at a first date."

[canyadigit]

Can you guys make crash course math? It should be from Algebra to Calculus. It would help lots of people.

Thanks.

[Marylandbrony]

The first law of Thermodynamics is that you don't talk about Thermodynamics.

[alonealien]

"Lisa, in this house, we obey the laws of thermodynamics!"

[CrAzYtothe]

This wouldve been super helpful in high school. My teacher couldnt really explain this and the whole class confused by this. I totally get this now.

[mnonymous]

Please do a crash course mathematics sometime soon

[mocha]

Slight correction: chemical reactions do not Create energy, they release energy.

[dannyt]

When I got thrown in jail no matter how long I slept on the concrete blocks my body never got warm..I use to think about that..

[berlytan]

I have to watch this 5x because I'm a slow learner. Hahaha 4 more to go. The beauty of video is that I can replay it and no teacher will be exhausted.

[filipmilinkovic]

5:47 What did you mean by that? Energy can be transferred through substance no matter what, so how can this internal energy not be able to leave the system?

[TheResidentPsycho]

Thermodynamics has always been my favorite part of physics

[luzelenatiscarenomontoya]

Excellent video to remember the basic concepts of thermodynamics, the relationship between open and closed systems, as well as the considerations that must be made with each of them. For a person who doesn't live with calculations that involve this branch of science, it seems a good tool to start learning. The graphics seemed right to me, especially when he explained the kinetic energy with the Star Wars character. <3

[xenophon]

Adiabatic process, otherwise known as the Gandalf Process

[Vaydore]

she's a great teacher!! I love watching these videos!! this is my favorite series by crash course!!

[EvocativeKitsune]

Thermodynamics is by far the least intuitive part of my Physics class work. Though I've struggled with, I'm glad I get it now. I hope you cover thermodynamic cycles!

[abdallahmanasrah]

I find that setting the replay speed to 1.25 helps much with viewing this series

Good job everyone