Since the question has come up in the comments: for the ramp problem, we're turning friction off for the square, but back ON for the sphere, so it can roll. Yes you are all correct, it would not roll without friction! :) 9:58 - "And then WITH friction, the spherical cow is going to roll."

Probably my comment will get lost...... But I just want to say that I saw her videos which were 8 years old..... And the way she made progress is truly impressive...... From a few subscribers to 1.76M subscribers..... From 2 mins small experimental videos to 30 mins descriptive videos... This is how she made her progress..... You always deserve a 👍 from us..... Well keep it up .... Will wait for the next vdo .....✌️✌️✌️✌️✌️

I got a sci oly competition this Saturday and this is what I’m missing for the machines event thank you for uploading this!

HELLO! Thanks for the great course! May I make a comment about the demo of 15:20 of weird water movement (if I understood your video correctly)? The reason water seems to move forward to the motion of the water pipe is not due to increased speed of water to maintain the same angular momentum. If that was true, then in around 16:12 where the water almost curls back to the same radius it would return to the same spot too. When water leaves the pipe, water droplets start moving in a straight line and won't continue rotating with the pipe. And where they end up in a few moments related to the nozzle makes you think they went ahead, while all of them were just moving straight. An animation would explain it more clearly! So what we see is an illusion of water moving ahead of the spin while it is not. HAVE FUN!

Just a little correction: When water goes outside from the pipes and at the same time they are turning around, water will have a tangential speed to front and radial speed to the outward. Because of this reason, they will have a direction near to the front. However as it is seen in the video, they curl back. BUT! this is an illusion. Actually, they are not curled back. Just as an example let's think about not radial but the tangential speed. For a simplification we have two water particles. The first water particle will have a tangential speed when it leaves the pipe and goes forward. Then, the second water particle also goes forward but it will leave the pipe after the first one. Because pipes are turning, the second particle will leave the pipe from a further position. As the two particles just goes on a straight path, the second particle will have a path near to the front compared to first particle. As we think about all particles this way, first left particles looks behind and it seems like while the pipes are turning, water curls back. As a result, this is the reason of illusion why water just goes on a straight path but not curls back actually. And also in order to avoid from some misunderstood: The pipes that has water output to the middle works in the same way. Water particles follows straight lines and as the pipes are turning, they are seems to behave like they are approaching to front and turning outside. There is no words to explaining them with using angular momentum. It is already correct. As it is mentioned in the video, angular momentum is conserved. Also, as I mentioned here, water particles will follow the straight path and they will not curl anywhere, so it is normal that there is no reason to have change in angular momentum. So also just think about this way. Have a nice day :)

"Done being Humerus" 🦴 . Good one 🤣🤣

I have a question, is this course going to continue after high school material is over or are you planning to start another course including calculus and higher-level subjects?

Thank you diana for doing these science lessons, I don't need them anymore but you really help out many people with these videos.

The “trick” with pipes and water has even more cool physics! Try to explain the curve of the water flow from the rotating frame of view - here how you come to the non-inertial reference frame and related inertial forces

These videos are so well paced. Love this series!!

EXCELLENT again Professor! You bent my brain from the very beginning of this video! Thank you very much.

I can’t thank you enough for sharing your wealth of knowledge and taking the time to simplify this for everyone

Great format. Good to see you still make videos.

I love this stuff! Thanks so much for explaining it in a very easy-to-understand way....

Thank you for sharing your knowledge with the world like this! You’re a treasure! 💖

I just love how you present the lesson 😊 Whenever I watch your videos it put smile on my face

Your such a breath of fresh air !!! I love your channel keep it up Girl!!!!

Thank you for existing, I love you.

sprinkler boi

I really appreciate your effort and this is exactly the kind of stimulus that youngsters need, this is going to be key for millions of young minds to step forward and pick up a STEM career.

I have an AP physics test tomorrow, Im really thankful for this series as I can review a bunch of stuff that I haven't done in a while.

Thank you Dianna for your great physics videos❤️❤️🔥🔥..

great lesson! moment of inertia is always a tough concept and demonstrations are such a great way to supplement the mathematical modeling! excellent work my friend! :)

The water pipe experiment is amazing! ❤❤❤👌👌👌👌

You got me with Rodney Mullen (Yes,I am a skater),now I've been learning physics thanks to you.Sending you a virtual high five and a big thank you from Australia.Tim ♥️s Dianna.

It turns out you personally have enough strength to spin the Moon: you did it with Jupiter!

"Spherical cow" said repeatedly with a straight face. XD

A great concept, i really love the way you teach. Thanks a lot for. I want you to please upload a video on absolute gravitational energy.

best physics teacher ever🤩

this video was recommended to me out of nowhere. I'm a freshmen who is not even able to take physics. I'm now going to learn physics from you because I do want to take it and if I take it now I can ace it later. big brain moves.

Thanks Diana for helping me grasp my subject so much better

From a long time physics teacher, good job Diana!

Just found this channel. I wish there were more people like you. The world have surprisingly uneducated youth... Best of luck.

Hey diana, just don't stop these lessons, because I love your background😅( but your explanation is equally good)

Thanks for yet another one of these videos! By the way, where did you get the cows? Thanks :)

I can see your audio, video, presentation-quality improving day by day, Kuddos diana.

Thanks Diana ,you made physics fun.

wow i just asked alexa who her favorite youtuber is and she said u! so i decided to check out ur account and its so cool! :D

10:52 there's no friction, why it would rotate.

just the one video & instantly subscribed

I'm surprised to see all the rotational mechanics described without using vectors! I knew you could do it, but I always found that it starts to get messier to not use them when you start to tackle harder problems. But vectors are also a bit more unintuitive at first, especially when trying to describe rotation in a way that's similar to how people are taught linear motion, and I think you've done a really great job at bridging the two in a way that's fun, easy to digest and clear!

This is a excellent video 👌. Easy to understand. Thanks.

Sweetest explanation ever😍😍🤩🤩 useful for exams !!

Well this video was amazing . I learnt a lot from this . Angular momentum topic was very interesting for students like me .

Very pimp and i'm glad to see Kari Byron again, i was a fan of Mythbusters too and it's a show for everyone that i miss here, in the Spain's TV; happy new year!.

I am your recent subscriber and I got addicted to your videos

I like your spin on this topic 😀

I knew the water is going to jump ahead because I have already watched Steve mould's video. Great video btw

I 'm your very big fan... Thanks for your videos

Thank you so much Miss Dayna.🌈

Great explanation and the sprinkler thing is so cool, but I think that technically there is a "more" correct solution to the problem with the velocity of the sphere vs cube cow, if there is no friction in both cases then there is no force to get the sphere cow rolling, just like when you throw a bowling ball it mostly just slides, so in the end they would slide down the ramp with the same speed. I think...

You are awesome. Thanks Diane.

At work sat at my desk and saw the water going forward. 😯 Ok now I need to watch.

Water is great analogy for space or energy flow

The classic demonstration of angular momentum is a figure skater doing a spin - they pull their arms close to their body to speed up their rotation (which increases the number of points their routine earns)

Thank you, Diana!😊😊

She keeps all the mathematical stuffs very simple and make the topic as practical as she could. I feel like, I am having a crush on her

Lol and I was thinking why would you expect it to do anything else?! 😆

Great series Dianna! Is it common to call all electromagnetic waves 'light'?

Not gonna lie.. for a second, I thought she broke the Matrix with that sprinkler.

I am a huge fan of yours! Do you ever do Q & A with your fans? How can I connect in a meaningful way with you, without taking too much of your time?

Hi Diana, is that not the Coriolis Acceleration leading to that strange water curve? Thanks!

Nice lesson, well illustrated.

Just a funny observation. If you line up all the people on earth at the equator each human would only have 5mm space to stand. And most of them would need to know how to swim. But still a very nice idea to use this to explain Angular Momentum. Keep up the good work Dianna and crew.

Well, Destin from Smarter Everyday has shown this experiment before. But it's fun to watch Dianna explaining it again.

1:05 I knew because Destin from SmarterEveryday and Steve Mould did a video about it. kzfaq.info/get/bejne/g5pdf5uGzLbPf58.html

you made super cool video. I have a couple of questions to which confused me for long. 1) when did the quantity of matter (mass) come into people's mind? 2) how was it figured out ? by who? Newton or someone else? 3) I think there must be a relationship between an area of shape with some newton physics...but i can't figure out what is it....will you pls explain it a bit if you are spare? thank you

I knew it would go ahead of the curved tube because I saw Steve Mould's video about the same thing. Then Destin (Smarter Everyday) and Steve did a colab about it and filmed it on a Phantom.

My 2 key takeaways were: 1) The skeleton laying on the floor was distracting! 2) Pulsar = Cosmic Lighthouse! 😊 These Physics lessons are great!

The second the spherical cow showed up I knew this was gonna be good; did not disappoint :)

I think, perhaps, a way to understand the extra energy in the sphere rolling (versus sliding) down the slope would be to tell someone that they need to bring the sphere and the cube to the top of a cliff and then drop them off the edge, straight down. But, the catch is that the sphere must be spinning when it hits the ground. This might not seem like a big deal for the little cow sphere, but if it was a 1 ton sphere then you can bet that the person would remember having to put the extra effort into getting it spun up before dropping it.

The heat of the sun's atmosphere at mercury's orbital distance pushes it away slightly more than gravity pulls it which accounts for mercury's slightly odd orbit. I figured that one out a couple decades ago. Mercury got caught a little close for its density and hasnt worked into its kush spot just yet. And being the sun's gaining mass at a way faster ratio than mercury is able to keep up with its pushing it at a measurable level.

Please continue this series for physics above the High school level as well

I'm enjoying these as a refresher for my long ago physics studies. BTW, you're a much more engaging instructor than Mr. Kendrick. Question however. Having watched all these, why aren't cows a unit? Or should I take that question to the philosophy review?

Hi Diana, awesome video, I only have one doubt which is the following: if the plane has no friction, how does the spherical cow start rolling? I thought rolling needed friction to happen

You're good! Keep it up!

Do hardwork every day 💛

I was very curious to find out what is the relation between angular momentum and that skeleton

Just Awesome..!

I love this content.

Sphere vs Cube down a frictionless slope question: if there is no friction then the sphere would not rotate, so would they not both get to the bottom at the same time?

Hello Physics Girl I have a question maybe you would point me in the right direction . When an aircraft propeller spins on a craft called an airboat ( everglades swamp boat ) there is a centrifugal load on the prop blades . If the boat changes direction with the prop spinning and creating this centrifugal load there is a gyroscopic action where the spinning prop resists the change in direction of it's axis . What is that resistance called ??? I really would like to know,,,, please . Thanks Ed

The outfit is very true to character. Very teacher - ish

Loved the video. However I think earth is more like 6x10^24 kg. Also, do pulsars really blink optically, or rather was it just the radiopulse that gave them their name?

Good morning, Please clear the following doubt I am having since 42 years. Sound travels faster in solids than liquids or games but when we close a door why the volume of the sound from outside gets reduced instead of increasing. Second doubt: When a magnetic object is magnetized, north and south poles get separated so there should be a change in shape of the magnetized subject but it is thought that the shape doesn't change

Woooooooww Great Explanation

why TF people just watch the video and go on ? she deserves likes for her efforts these concepts in front of us !!

Thank you.

Hi Dianna, I have doubt in the sphere and cube in ramp puzzle. If the friction is considered zero(0) then there will be no rotation in sphere ryt. Correct me if I'm wrong. Then the answer for this question will be both sphere and cube will reach the bottom at the same time. It is similar to free fall.....

1:02 - "And if you guessed it would jump ahead, idk how you knew" - Well, if you're subscribed long enough.... 😉 And I love it when you ask a tricky question, then we probably all think "Ok so the obvious answer is A. so the real answer must be B. ... But why...? 🤔" - And then the real answer is far cooler then we even thought 🤩 (Although if you learnt physics you know the answer, but it's still so cool to see it gets solved 😉)

Ok. Super amazing video with a super amazing host. I just subscribed. There's a interesting caveat to this angular momentum thing and the earth's spin. Occasionally the earth's spin varies. Like, all the time actually. Very, very small changes though. In the year 2020 the earth beat it's own spin time for a day a total of 28 times. That's the most every recorded in a single year since recording started around 50 years ago or so. One more reason 2020 was just... Fill in the blank.

1. I clicked for seeing what you do with a skeleton. 2. You should have collaborated with Steve Mould

You have so many energy!

2:30 I had to watch again to understand what she said because my brain was more curious about the spherical cow in the first attempt! 🐄

does rotational mass effect the gravitaional forces that the mass holds? so a spinning sphere with its tidal forces and any tidal forces or weather effects also affect the overall gravitational effect , rather than a general body of mass behaving as a whole with one effect ? can rotaion and spin add so much extra energy across various mediums?

Unbelievable!

I thought the water pipes turned inward was a demonstration of the coriolis effect. Should I be envisioning the coriolis effect in terms of angular momentum?

Today was my birthday so I will take this as my gift Thanks

8:33 that is an amazing sphere!!

Excellent! :D