Kinetic Theory and Phase Changes: Crash Course Physics #21

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How the heck do we map out a planet without oceans? NASA had to figure that out when we sent the Mariner 9 probe to Mars. There’s some tricky, yet fascinating science behind all of it! In this episode of Crash Course Physics, Shini talks to us about sea level, kinetic theory, and phase changes.

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Novojit Saha says:

*kinetic energy

relafen66 says:

Man this is worse than my professor, your talking waaaay too fast.

Mark Holm says:

Commenters on this series have frequently complained that the material is too advanced. This is disappointing to me since the level of the material is the same as standard high school physics with a bit of calculus added, and since the series got into gases, a bit of high school chemistry.

I wonder if another attempt might be made, introducing physics through the common laboratory experiments used in high school and college classes? The first experiment in my high school physics class studied the acceleration of a falling weight using distance vs time. It is pretty real when you measure the distance intervals on a paper tape using a meter stick, and plot them to find a nearly perfect parabola.

eyeammi says:

@8:05 "Mars Attacks!" reference point…

Gerald Ellis says:

damn lady slow down!!!!!!!!!!!!!!!

#A little abstrction wont kill ya

Alan Yessenbayev says:

Kenetic energy… Yeee

Christoph G. says:

I was so curious what happens if you step over the critical point by rising the pressure and the temperature a little bit more. I found out that you reach the realm of super critical fluids which behaves like liquid and gas at the same time.

nervetonic1 says:

Speaking as an old fellow from the days of pinball and UHF television, I must ask: can you kids really follow this lecture? That is, can you understand this lecture at the speed she is talking, where they edit out any pauses from between sentences? Honest question.

Joe Moore says:

On an off topic… Crash Course Linguistics?… or Geography?… please…

Leyton “Filth” Jay says:

You are brilliant and as you're British I believe you just a little tiny bit more than the American Brothers, dunno why.

Iain MacLean (Radioactive Yeti) says:

They didn't even mention plasma once….

Why? ;-;

Luís Romano says:

Well I know the chances of you answering me are incredibly low, but I do have a question and I hope for the slight chance to occur:
During the mission planning, was it considered the actual atmospheric pressure measured or was it relevant to evaluate the hypotetical atmospheric composition of a determinated previous condition on the planet to set the reference point as the triple point? Because, if I'm not mistaken, there would be an increase on the pressure gardient with a thicker atmosphere causing a decrease on the altitude of the reference point, leading to a deviation on the data analysis on further stages of research if you were to compare to anything we can measure or quantify here on earth. Meaning you'd need to look for something "deeper" than you'd think it should be, am I wrong?

jennifer jacobs says:

I know this is dorky…but i love awtching these videos just for entertainment! But i like it when John Green does the teaching for History! But overall, this channel is….DA BOMB!

Peichen01 says:

1. Why is PBS funding a series where the host speaks strong British English? It makes the video less easy to understand for American and ESL speakers. Unless she is special (like Stephen Hopkins) I see no reason why PBS cannot find an American to host.

2. She needs to talk slower. If may be a YouTube video but science is science. Rushing through all the formulas might make the video more hip/interesting but it doesn't explain things well.

keghn feem says:

I could never find a extensive resource of phase diagrams for atoms or simple molecules.

Adrian Inniss says:

this is amazing!

Jabberwocky says:

6:34 So what happens if the pressure is above critical pressure and the temperature is above critical temperature? That seems like a contradiction, unless it depend on what critical value you get to first.

Jose Eduardo Guzman Crespo says:

slow down…?

Anders9009 says:

The opener is kinda hilarious if you think about it.

NaquadahEOD says:

Kinetic Theory and the Phase Changes would be a pretty awesome band name.

Hansie Cronje says:

she's pretty, why is she dressed as a hipster lumberjack, get her a dress. except is he doesn't want to were a dress.

oxXORainierOXxo Tayam says:

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| Windows has detected that you are too smart. |
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|     ̄ ̄ ̄ ̄ ̄ ̄     ̄ ̄ ̄ ̄ ̄ ̄     ̄ ̄ ̄ ̄ ̄  |
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Anthi Pappa says:

Please talk slower

transylvanian says:

i like crash course in general, but i have to say i really think they missed the mark with this series. perhaps i'm biased since i have had quite a bit of physics and math education – so don't take me too seriously – but i think the way it's presented is entirely wrong. Usually, I can enjoy the crash course videos for what they are: a way to teach the layman some of the basics in a fun and easy to understand way, which is why i was looking forward to watching these with my girlfriend, but i have to say instead of being fun these end up being a bit of a snooze fest.

I'll skip over how i would like to see more maths and proofs since i already said i'm not the intended audience but honestly, this series isn't too great for those without a background in physics either. i think people might have a hard time keeping up because the presenter speaks very fast, and while that in itself is not a problem (the videos are pauseable after all) it is exacerbated by the presenter cramming in too much information into her sentences and trying to be as precise as possible with her statements. this becomes detrimental to the presentation but i think is ultimately just an artifact of the deliberate choice of trying to put equations into words. this style of communicating works wonderfully in writing, but it's very irritating when spoken.

and the other problem with the presentation is, too often a visual accompaniment to what you're talking about is missing. show graphs, maths, experiments etc. – yes i know there is a decent amount of that in here, but there should be more (or just stay longer on the screen). all scenes in these videos where the narrator is talking to the audience without some equation or diagram or animation overlaid on the screen are just opportunities for the viewer to lose interest. it makes it hard to focus if it's all talk and is not at all engaging.

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