We made quiz questions to help you review the content in this episode! Find them on the free Crash Course App! Download it here for Apple Devices: apple.co/3d4eyZo Download it here for Android Devices: bit.ly/3TW06aP
@SnoozeTheRecluse4 жыл бұрын
I'm learning my whole semester in one day
@phathumudau2235 жыл бұрын
"you know how physics loves ramps, especially hypothetical ramps" , please tell me something more true than this
@aksharaa53764 жыл бұрын
passive-aggressive physicists
@DapaChrons4 жыл бұрын
the key to watching these videos is to pause to think on and rewatch certain moments if you don't grasp them immediately. These videos also help in conjunction with reading or other videos. I'm here because my physics textbook didn't explain what torque was but launched into a 15 page discussion of magnetic torque
@pandacutiesuperstar6 жыл бұрын
Its not that she speaks too fast, its that they expect you to have a background in this, its like a review
@pranavkulkarni14144 жыл бұрын
The jump cuts don't help either.
@gusbisbal98034 жыл бұрын
I have a back ground in this and its treating the fundamentals like its something we can just skip over. Like the units of torque are crucial to understanding torque. ITS NOT A FORCE!!! is what it tells you. As soon as you say its not a force then the question of what is it really???? can be answered. Thats when you begin to understand it.
@barockassegid99124 жыл бұрын
@@gusbisbal9803 This is called CRASH COURSE FOR A REASON. SHES SUPPOSED TO HELP REVIEW THE BASIC TOPICS IF YOU WANT SOMEONE TO HOLD YOUR HAND AND WIPE YOUR NOSE FOR YOU, GO TO YOUR TEACHER OR KHAN ACADEMY
@shreyaprakash4 жыл бұрын
For anyone watching Crash Coures physics for the first time: Dont get tensed by watching these videos.. These videos are best for reviewing the concepts after learning the topics beforehand.. They are not recommended for anyone who wants to learn these concepts afresh.. Dont freak out after watching these videos, it's fine!!
@kikumayumi92194 жыл бұрын
the whole point of crash courses is to get people an understanding of a subject, not to review it
@shreyaprakash4 жыл бұрын
@@kikumayumi9219 Exactly! And that's what disappoints most of us watching the videos..
@kikumayumi92194 жыл бұрын
@@shreyaprakash how so does it disappoint us, this crash course was a great help for me when I watched it
@shreyaprakash4 жыл бұрын
I think you must be having at least some basic understanding of these topics.. My point is that people who want to start learning physics or those who have no background knowledge of the subject will find it extremely hard to grasp the concept.. It's a generalized view..
@xSkyHigh128 жыл бұрын
I really like the way she... torque
@caihui56978 жыл бұрын
HAHAHA
@enriquea968 жыл бұрын
good one brah
@marcelinatuszynska978 жыл бұрын
OMG AHAHA. THIS SHOULD WE TOP COMMENT
@enriquea968 жыл бұрын
yes he definitely got me xD
@wavinsouth73278 жыл бұрын
loool
@bootswiththefurr47187 жыл бұрын
"Have you ever pulled a door open? Me too!" I love it. 1:04
@NarekAvetisyan8 жыл бұрын
I understood none of this. But, I feel smarter after watching this video.
@SunriseFireberry8 жыл бұрын
The One Ring comes third, but it rules them all!
@benaaronmusic8 жыл бұрын
...and my axe!
@arcaderockstar75368 жыл бұрын
RISE!
@ricodelta18 жыл бұрын
I have a cock ring
@ddmagee578 жыл бұрын
A male chicken ring?
@pietrocelano238 жыл бұрын
One Ring to rule them all, One Ring to find them,One Ring to bring them all and in the darkness bind them.
8 жыл бұрын
I have a degree in theoretical physics, and I just adore this series!
@KingJokerRock7 жыл бұрын
A science lesson with a mario box, the one ring, and a dragon ball.... I'M IN!
@mukundyadav44456 жыл бұрын
KingJokerRock also the ring is from 'lord of the ring'🍻🔥
@noabsolutelynot36605 жыл бұрын
@@mukundyadav4445 that's why he said "the one ring" that's what it's called
@biggbuck95355 жыл бұрын
Should've used a power ring from Sonic the hedgehog. Then it would've moved faster down the ramp? 🤔 Lol
@begonthotiana94875 жыл бұрын
my kind of lesson
@andersalexanderandersen50228 жыл бұрын
These courses are pretty good for brushing up on - or repeating - physics classes, but I don't think they're very useful as a introduction to the subject. I understand that you need to solve problems to get to the core of physics, but listing a bunch of equations and explain their consequences isn't going going to give most of the audience a deeper understanding (this is an assumption!). I know the course would be taught in a much slower pace, but for really interested audience with a first hands experience, this is not building a solid foundation (in my opinion). I think it should be a blog post deriving all the equations displayed in the video for those who need a solid understanding of the equations. Don't take me wrong here, but I think this would please a bigger audience than the current setup.
@FirstRisingSouI8 жыл бұрын
I agree. I think it would be better if the math were mentioned for reference, but the instruction kept mostly to the conceptual.
@IoEstasCedonta8 жыл бұрын
I'm not sure how much more conceptual you can get than this...
@AlbertoMartinez-rk2lf8 жыл бұрын
You may be right in some way, but in my opinion the most important thing is how cool is this vid so people like me, with no background in physics, take interest in this topics
@Csilaverte8 жыл бұрын
I disagree. Most of the edutainment videos on KZbin are lacking the solid, somewhat rigorous aspect of that particular branch of science they currently teaches. These CC Physics videos do not: they have it in the form of the necessary math. The best thing about them that they serve not just as introductions, but also -as you have stated- help brushing up on previously attained knowledge, refreshing them. I'll write the exact same thing i am fond to say about this topic: if you are not interested in the nuances of mathematics, physics is propably not for you.
@Mukation8 жыл бұрын
That's why it's called "crash course". It's not meant to be equal to an actual physics course in a school.
@yasmeenhayat13788 жыл бұрын
I actually really enjoy how this course is set up. It explains the basic concepts behind the equations so that when you go and practice the skills, you have a general idea on how to tackle them. I have to agree with the feedback others have given - you do whizz through the material. However, this medium can handle that, as you can just replay portions of the KZbin video. Keep up the good work!
as usual, it's going to take a week to assimilate and fully understand the video :)
@oscaralonso46998 жыл бұрын
same.
@PuffleBuns8 жыл бұрын
isn't ur face profile from an anime? I think its name is Greed?
@Pipiopy8 жыл бұрын
King PufflePuff spirited away
@PuffleBuns8 жыл бұрын
Yeah, that's what I thought. xD
@nathanj24396 жыл бұрын
King PufflePuff its original name was No Face
@wakimaniac8 жыл бұрын
I slept through a physics class one time because I was tired, they explained torque. The teacher wouldn't explain it again. It's been two years, but now I finally understand this concept. Thank you so very much.
@jakubbuzalka22264 жыл бұрын
This video feels like a huge injection of liquid physics into my brain. Thank you!
@MartijnvanWensveen8 жыл бұрын
Moments of silence.. This video has none!
@RainbowManification5 жыл бұрын
Nope, just inertia
@shaheer_ghazi4 жыл бұрын
I just spent 5 minutes of my life opening and closing my door at difference angles and lever arms
@ganaraminukshuk08 жыл бұрын
"We have a box, a ring, and a marble." (Mario cube, LotR ring, and dragonball appear on ramp.) This is gonna be good.
@karanmehta57535 жыл бұрын
to everyone saying that she is talking really fast.. that is because (if you haven't noticed) the channels name is called crash course and hence they have to explain topics quickly. I think that these videos are like reference materials that you can use to understand concepts quickly once you have a brief idea of the concepts.
@DanGash6 жыл бұрын
I'm giving Crash Course a shout out on my graduation... in 2 weeks!!
@ogliara64734 жыл бұрын
Thank you for helping me through my physics assignment. Great video!
@cherri_tsuuuu7 жыл бұрын
now you know you should buy your future wife a box so you guys can have a smoother relationship
@davet52235 жыл бұрын
Don't forget to put the ring inside the box
@zoeferrier8584 жыл бұрын
@@davet5223 Ayyyyy
@minghuiliu4516 жыл бұрын
If kinetic friction is not allowed, why will the marble and the ring roll instead of slide down?
@giovanniadelfio5378Ай бұрын
Thanks, this was the exact problem my professor asked me about in the oral exam!
@zacharykrawczyk39426 жыл бұрын
There's an error at 6:27 the second part of the equation has KErot labeled as "kinetic energy of translational motion" instead of "kinetic energy of rotational motion"
@abdulrakeebalsarori81715 жыл бұрын
I am sorry, but how would the box get down before the ball or the ring? We already assumed that the surface is frictionless and so there would be no friction force that would cause the ring, or the ball, to rotate. Therefore, there would be no loss( or transformation) of potential energy to rotational energy of either the box or the ball.
@missychuu8 жыл бұрын
She is gorgeous btw.... And I love her hair 😍
@willzer8088 жыл бұрын
God yes
@pairot018 жыл бұрын
She is, not that it matter really.
@feldinho8 жыл бұрын
stop objectifying her! she's here to teach physics!
@willzer8088 жыл бұрын
Felds Liscia whatever, everything is relevant
@charliehutch35338 жыл бұрын
go to India..they literally all look like her.:P:
@Kronimiciad6 жыл бұрын
If the ramp only allows static friction and not kinetic friction, then the box shouldn't go anywhere if it doesn't rotate. In order for the box to slide down the ramp it needs kinetic friction. Static friction would mean that the box is stationary.
@tommclean92088 жыл бұрын
Im doing Marine Engineering where there is a dynamics module which I did just not understand at all, these videos are so useful. Thanks.
@jomacr34 жыл бұрын
I could not get through Corona virus distance learning without this. Thank you!
@Lee_yourboylee8 жыл бұрын
Love it, a very helpful accompaniment to my textbooks. Thank you Crash Course.
@rafaelwilliam38054 жыл бұрын
7:17 i almost had a heart attack, i sat in the libary and thought it was a school shooting lol
@SauceyNoodle7 жыл бұрын
Learning physics from Symmetra
@imjustsayin347 жыл бұрын
First time using crash course for physics and was expecting hank but I was pleasantly surprised the speed she talks is nice
@FirstRisingSouI8 жыл бұрын
Watching at 1.5 speed because I'm a physics grad student, but I feel compelled to watch everything Crash Course puts out.
@HonestUsedCarReviews8 жыл бұрын
𝐓𝐨𝐫𝐪𝐮𝐞 𝐰𝐢𝐧𝐬 𝐫𝐚𝐜𝐞𝐬
@josephpark20935 жыл бұрын
This looks threatening.
@safa94085 жыл бұрын
My head has blown up, I wanna cry, and my acne is back after watching one video
@audreyandremington52654 жыл бұрын
I'll never watch LOTR the same way again.
@ezekiel06068 жыл бұрын
that pyshics theme song intro gave me chills just like the philosophy one
@alluringorchid57254 жыл бұрын
Thanks for helping me out with class 11 physics . Exam tomorrow
@nathanbanks23548 жыл бұрын
I love the Elvish characters inscribed on the ring! Now I know why it's difficult to roll a ring into a fiery volcano--it's better to get someone to bite it off your hand and fall instead.
@stephaniejoelstro17627 жыл бұрын
This series is so good.
@En_theo5 жыл бұрын
@5:05 Should it not be "kinetical energy of rotational..." in the bottom equation ?
@nekomatafuyu8 жыл бұрын
If the ramp is perfectly slippery, I'm wondering if the marble and ring would start rotating in the first place. As I'm picturing it in my mind, they start rotating due to the frictional force where they contact the ramp, but that force isn't there in this example (otherwise the block wouldn't slide (or at least would lose energy due to the friction)).
@Rhaegar198 жыл бұрын
Rolling objects use static friction because the point where they touch the ramp isn't actually moving (see last video).
@McGeias8 жыл бұрын
+Rhaegar19 no no no. The last video was an example of rolling without slipping. A frictionless ramp has infinite slip. There is no counterforce in this hypothetical example turning linear momentum into rotational momentum. Gravity does not impart spin magically. It's a linear force. It the surface friction that converts linear motion into rotational motion. That friction has been eliminated in this example. This is all just wrong.
@Rhaegar198 жыл бұрын
+McGeias Everything you're saying is right, except the ramp isn't frictionless. It has static friction. Rolling objects use static friction to convert linear motion to rotation. If you don't believe me or Dr. Somara, google it for yourself.
@sunrise6824 жыл бұрын
I swear to god no matter what im learning theres a crash course for it
@williamcoley18 жыл бұрын
If the ramp has no kinetic friction, then there is nothing to start the rolling motion of the ball and ring, ergo they would all reach the bottom of the ramp at the same time.
@seaniwu5 жыл бұрын
Linear momentum is the product of moment of inertia and the angular velocity if and only if the axis of rotation of that body is a principle axis
@voidspork71505 жыл бұрын
Note that the ramp is frictionless. If the ramp had friction, the marble and ring would likely get down faster (specifically, the marble) because rolling friction is less powerful than static/sliding friction. That said, the example is meant to illustrate how torque and conservation of energy work, so mentioning friction would be counterproductive to the video.
@asadgandapur99508 жыл бұрын
kindly also make a video on projectile motion!
@madLphnt8 жыл бұрын
The one youtube vid i look forward to all week!!! awesome
@madamii8 жыл бұрын
I'm 13 in eight grade and I'm watching this because we have to learn about it soon. Im trying to be above everyone else!!!!
@victorianightshade42378 жыл бұрын
Just refreshed and boom
@KrutarthBhatt18 жыл бұрын
Mr.Green , this kind of videos make crash course my favorite channel.
@damienscullytoo8 жыл бұрын
these physics videos are really helpful especially before my test
@davidlei30975 жыл бұрын
At 5:07, there is an error. The bottom part is suppose to say "rotational motion", not "translational motion".
@theblackreaper43954 жыл бұрын
Loved the video but in the case of the ramp, I'm pretty sure that friction between the box and ramp is kinetic, there is relative motion B/w the two surfaces..
@Alesster1016 жыл бұрын
This video cured my insomnia. Good morning guys.
@vicraaiman12054 жыл бұрын
What's about the friction they have when goes down? The box has more surface than the marble and ring, it means the box have more friction than the other. So it will be slowed down
@nobodyofnaught28 жыл бұрын
Why is it that the Marble and Ring even start rolling rather than simply sliding down the ramp with no rotation just like the box? I think there's something about the interaction of the hypothetical scenario where Static Friction exits but Kinetic Friction does not but I can't wrap my head around it.
@fredasanders39487 жыл бұрын
Hi this is Arwen I love Crash Course!!!!!
@ahmadzaidan76932 жыл бұрын
i like this
@himanshuoswal35405 жыл бұрын
6:57 One ring to bring them all , one ring to find them all , One ring to rule them all.
@laserwolf658 жыл бұрын
Am I the only one who thinks that Physics is too technical a subject to be adequately explained to the layman in a series like this, or am I just stupid and unable to grasp Physics?
@WeAreGRID8 жыл бұрын
its crash course, its basically assuming that you have either a background in the subject or are studying more than just this series. in my opinion she speaks way too quickly, each eopisode is a whole lesson, if a teacher was doing this each video would take an hour to demonstrate all the involved factors.
@G_de_Coligny8 жыл бұрын
agreed the girl talk way to fast. Had a feeling like vertigo just because of the speed of her speech, before being able to understand the words she was saying. I,m non native in english that might have made it worse... but it's not a rap battle... slow down pretty please...
@ph0n612348 жыл бұрын
Not sure if speaking fast is a problem (and this one is pretty normal for me and I'm not even native speakers, for fast try CGP Grey channel :) ). The good thing about video is that you can always rollback to sections you didn't understand so you can learn at your own pace, it's the whole point actuallly.
@G_de_Coligny8 жыл бұрын
for me it's too fast end of story. a good video should not have to be rewinded so you can grab the words. and the flow is definitely faster than other tutorial videos.
@charliehutch35338 жыл бұрын
or are you 'grasping' for replies?
@filipfilipovic29748 жыл бұрын
It was interesting listening to her torque about talk.
@bennemann7 жыл бұрын
At 5:05 there is a mistake in the video: it shows "translational motion" for the second line too, which shold be "rotational motion".
@InventTwig7 жыл бұрын
Correction ! : even if there is no external torque on a 'system of particles'/'particles' angular momentum is not always conserved(only for some special points. angular momentum wrt to allpoints is conserved when the rotating body does not have any angular acceleration AND the axis of rotation passes through COM. angular momentum of a point can change depending on from where you observe it (both in magnitude and direction).
@alexsarullo37534 жыл бұрын
The ramp example is flawed. For rotational energy to be taken into account, friction must exist to make the ring/marble spin. If the object make contact with a 0 friction surface, they cannot engage in spinning, they would just slide down the ramp.
@lightspeed20144 жыл бұрын
Alex Sarullo agreed
@lightspeed20144 жыл бұрын
It’s like kinetic friction works for the ring and the marble but not the box
@linshuang4 жыл бұрын
That’s crazy, I thought the box would be last and ring would be first since it looks like a wheels. Thanks Dr Shini Somara!
@DMikov8 жыл бұрын
I love your videos! please keep it up! May I kindly suggest to take a moment to breath... hehehe the paste is so fast! :) lil breaks :))
@edwardmcdonagh73098 жыл бұрын
you explained this way better than my university lecturer, good job!
@naserahmed98745 жыл бұрын
Did she give a lecture or she read out the lecture? How is it possible to continuously give a lecture like this?
@adriel40407 жыл бұрын
Okay, some of this stuff is a bit confusing but so much more confusing is the way teachers explain it in class. I swear i learned more in the last 10 mins than the last three weeks.
@user-jy3lt3dn1r6 жыл бұрын
The short video really did good job to make a brief interview of phsical knowledge.
@Roman-us2fp7 жыл бұрын
I tried calculating who would win the race but then I realized that the ramp was hypothetical so all of my calculations were wrong.
@user-xf9sw4wr8f6 жыл бұрын
Good video
@ImChrisNotChrist8 жыл бұрын
As a car guy, I very much appreciated that video. Solid host too
@scorpioninpink8 жыл бұрын
The only topic in Physics that I actually know at least a little.
@arunsharma42215 жыл бұрын
Thanks a lot mam 😊 . You are awesome
@TheBreaded8 жыл бұрын
If there is no friction on the ramp, the marble and ring wouldn't spin as they went down the ramp. They would just slide like the box does, at the same velocity as the box.
@Rhaegar198 жыл бұрын
You're right, but there is friction on the ramp!
@nandodando96958 жыл бұрын
That was clear and went right in. Thanks
@krossbow_8 жыл бұрын
I graduated 5 years ago, im a veterinarian, why do i enjoy learning about torque
@fahamedi8 жыл бұрын
They could've mentioned the physics of backflips, because when you jump and tuck your kness you decrease the moment of inertia of your body and you rotate faster due to conservation of angular momentum
@bidishamukherjee39367 жыл бұрын
best best best best best!!!!! i could not get the chapter while reading from book but crashcourse made me understand it soooooooooooooooooo wel!!!!! thanks a lot lot
@fabd19234 жыл бұрын
this video was very helpful, thanks guys
@eefje91224 жыл бұрын
at 5:07 the 2nd equation should be kinetic energy of ROTATIONAL energy, not TRANSLATIONAL energy
@sciencelover23428 жыл бұрын
If there is no kinetic friction, I don't think an object will roll.
@danilooliveira65808 жыл бұрын
what I was think was, wasn't the marble and the ring also supposed to just slide the ramp ? I mean, they need friction to roll.
@Woad258 жыл бұрын
No it still using static friction to roll. Remember, the point at the bottom of a round object as it rolls is stationary, assuming there's no slipping. So because it technically doesn't move you'd be using static friction.
@orcushelvetii96138 жыл бұрын
Thinking almost the same. But as there is a little static friction at the start, they will make a verry little bit of rotation just at the start, and then just keep sliding (with this little initial rotation). So, in a unperceptible way, i think the box arrives first.
@heysoymarvin8 жыл бұрын
But there is static friction, so I think that's why they spun
@joshuajonme488 жыл бұрын
Friction is what prevents an object from moving down a ramp, not what helps move it. The reason why the objects move down the ramp is the force the gravity. The force of gravity is always straight down to the Earth's center, so the component of gravity aligned going down the ramp is what moves the object down. Friction (static or kinetic) would oppose the force of gravity. The object moves when the force of gravity aligned with the ramp is greater than friction. Reasons why she is considering static friction but not kinetic friction: If there is static friction, an object that rotates about an axis, such as a sphere, will not slip. Static friction gives a force of gravity. The force gravity will cause translational motion, while that initial static friction will cause rotational motion. For objects that do not have rotational motion, such as the cube, will have no affect from that initial static friction other than breaking through the threshold of friction. If there is not kinetic friction, then we won't lose energy when moving down the ramp. If there was kinetic energy, the cube will move down the ramp much slower than the ring or the sphere because more of its surface is in contact with the ramp to be affected by friction. Kinetic friction causes energy lost, so rotational energy and kinetic energy will not equal potential energy as the video shows. Also if there was kinetic friction, the results of the race would be different. The sphere is only in contact with the surface at one point, so it would have the least lost of energy from kinetic friction and will get to the bottom first. If I made any mistakes or left out any important information, please let me know.
@marinairitsyan Жыл бұрын
Very detailed explanation. Thank you!!
@9000Arko8 жыл бұрын
dont you love when Pharah is teaching you about torque
@RHTQ14 жыл бұрын
Anyone else here studying for online makeup AP exams because of the stupid submit glitch? Because I am so upset about it... I was so confident about those other FRQs!😭😭😭
@SquidTheSyd5 жыл бұрын
This video gets real, quick.
@pwa30947 жыл бұрын
I would challenge the outcome of the Ramp Race. If there is no kinetic friction on the ENTIRE ramp, then I do not believe there would not be any source of energy (torque) to rotate the marble or the ring. Hence the initial kinetic energy of the ring or marble would not be converted to rotational energy in the marble or the ring. Also since the only forces acting on all three objects, absent kinetic friction, would be "g" (gravity) and air resistance, I think the ring would win the race because it offers a smaller surface area for air molecules to act upon (drag), ignoring the effects the race because it offers a smaller surface area for air molecules to act upon (drag), ignoring the effects of laminar flow and potential vortices. thoughts?
@secondo927 жыл бұрын
Yeah you need friction in order to make the marble and the ring rotate. But since there was no friction on the ramp, the marble and the ring shouldn't rotate, they should just slide down the ramp. Since the ring is tiny and hollow I assume it has the lowest mass of all 3 and thus less inertia. Less inertia means higher velocity when you convert potential energy into kinetic energy. You are right.
@frank2603326 жыл бұрын
Another person who has sussed out the teacher as not living in the real world.
@adamlevy89715 жыл бұрын
These videos are incredible. They are really helping me with my college course. Thank you! :)
@shairiaaz82986 жыл бұрын
i am really surprised how you taught that........i didn't ever felt it that easy and intresting......i must say good job
@infinitasalo4724 жыл бұрын
This helps a lot, just what I need for exam review!
@AmirMohammad-fd9nr6 жыл бұрын
that helps me a lot .GREAT THANKS for your useful videos.