Uniform Circular Motion: Crash Course Physics #7

Did you know that centrifugal force isn't really a thing? I mean, it's a thing, it's just not real. In fact, physicists call it a "fictitious force." Mind blown yet? To explore this idea further, this week Shini sits down with us to discuss centripetal force, centrifugal force, and a few other bits of physics to help us understand uniform circular motion.

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Mark, Eric Kitchen, Jessica Wode, Jeffrey Thompson, Steve Marshall, Moritz Schmidt, Robert Kunz, Tim Curwick, Jason A Saslow, SR Foxley, Elliot Beter, Jacob Ash, Christian, Jan Schmid, Jirat, Christy Huddleston, Daniel Baulig, Chris Peters, Anna-Ester Volozh, Ian Dundore, Caleb Weeks

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[crashcourse]

We made quiz questions to help you review the content in this episode! Find them on the free Crash Course App!

[dezent]

She kept me totally focused for nine minutes and twenty six seconds and i learned lots of new stuffs i did not know before!. Really shows that you guys are getting more and more professional.

[mufaddalezzi]

just an idea, you should have an app where you can compete in a quiz with a stranger based on the material from your videos. It would help learn better.

[AxisSpark]

2:45 The fact that phys is a required course for Computer science majors with a concentration in game development and crash course incorporates video game references in these videos makes learning all the more enjoyable!

[WriteUnread]

Please god someone fix that Rubik's cube I'm dyin here

[vectoredthrust]

"We're just here to make sure the ride is safe, we're not responsible to clean up all the vomit after the ride is over"

Bahahaha, I'm sure the engineers agree xD

[krismoe]

I am at the bottom of motivation atm and I have a physics/chemistry exam in 1.5 weeks. So nice to have easy "lectures" on youtube. Thank you guys!

[fredschwartz]

Great video. I'm close to 70 and live in the US, but when I was her age, we pronounced about 73% percent of all those big words differently :-) , Love it. I could listen to this video a dozen times. (and might have to . . . and take notes)

[killersquirrel]

I just failed my ap test this week, really could have used this earlier rip

[simplySwag]

I remember when i was back in 8th grade i couldn't understand a thing she said. I jus thought she was one bad teacher with crash course. now in tenth grade, this is the most clear explanation i have found yet. Thanks!!

[TGC]

You spin me right round... Thank you for your time.

[seantimchew]

Bless you guys, this has practically saved my GPA. So much easier to understand than what's taught in school

[meredithmcdonough]

currently watching this 3 hours before my AP test. god bless your soul

[SotraEngine]

This will save me in the physics exam in 12 days

[TheWizardYoshi]

Circular motion was my favorite section of physics last year, awesome video!

[nachannachle]

It's interesting to notice that as we go further into these videos, the explanations make more and more (intuitive) sense.
That's is great course outline work, folks!

[dm_nimbus]

Why is Crash Course always awesome? Is there some quantifiable element?

[perpetualpolymath]

1.Lets prove a = v^2/r if v = (2 x pi x r)/T
2.v= (2 x pi x r)/T
3.using chain rule
4.dv/dr x dr/dt = dv/dt = a
5.therefore dv/dr x v = a
6.dv /dr = (2 x pi) / T
7.dv/dr x v = ((2 x pi)/T) x ((2x pi x r)/T)
8.dv/dr x v = (4 x pi^2 x r)/T^2
9.dv/dr x v = (((2 x pi x r) / T)^2 )/r
10.we know that v = (2 x pi x r) / T
11.therefore
12dv /dr x v = v^2 / r
13.hence
14.a = v^2/r
15. Q.E.D
if anyone is confused at 9 a quick expansion shows that line 9 equals line 8.

[LucasCamargosRamos]

1:21
I was pretty concentrated on the video and thought I was just about to pass out.
Well played. 10/10.

[ExplodingPinapple]

2:47 Oh hi there, Link! How are you?