Professor! I figured the solution by creating a vortex when I was cleaning my toilet... :) Glad to see it was correct. Please don't stop blowing my mind. Thank you so much
i also discovered this when i was 12 or 13 as i had to empty milk P.E.T.s in in 5l pot and had to do it preferably fast an without splashing i'm not saying that i'm smarter than anybody just i feel like if you are aware of your surroundings than is easy to figure out many physics problems
Love these video's! You don't need to limit yourself to things that haven't been "answered" on the internet, your way of demonstrating and explaining the problems is great. Keep them coming.
When watching the video where you posed this question, I had the intuition to spin it... Surprised that this was the answer!! I guess it's something we see very often, emptying a filled sink starts by bubbling but then evolves to a less resistive mechanism by introducing a spin. Thanks for this video.
Thank you so much professor. I am a student from the University of Florida, but I truly learned Physics though your 8.01 and 8.02 lectures. I always think of you as one of my best professors who helped me realize Physics is very beautiful.
I remember when I started to study physics in 2010 with my girlfriend. Almost everyday when we came home from the university (University of Helsinki, Finland), we used to watch your lecture about the subject we just learned. And that helped a lot! Although the lectures in our university are very high quality, your lectures are superior! Your teaching style is very clear, entertaining and the demonstrations... They are just wonderful! Actually a few of my friends, who didn't like physics before, became interested in physics because I showed them your lectures. I'm so greatful to you (and I think I'm not the only one)! Thanks for all you've done to help people, not only to understand, but also to ❤️ physics!
My mother challenged me and my brother with this vortex method about 50 years ago. I have no idea where she got it. I was doing pretty well by shaking up and down to allow air a more free way up, but her vortex was more consistent. By then I had already some background of physics and understood what was happening, I have used it to my advantage ever since. I found your lecture videos recently and have greatly enjoyed them. Some of them are refreshment courses for me, but your presentation is always unique and exciting. I hope you don't quit your presentations any time soon, no matter any reduction in viewer numbers!
Hello Professor Lewin! I am a student who is currently attending the University of Missouri Science & Technology. My goal is to graduate with a major in computer and electrical engineering. I wanted to let you know that I am one (among the millions of others) who has gained a lot of incredible knowledge by watching your lectures on RUclips. It started out with me needing some help in my first Physics class a few years ago and now I find myself watching your videos all of the time just for entertainment! You are an amazing professor and I would be honored to meet you some day. Even if you do not read this, I just wanted to say thank you for everything you've done. You make learning exciting and enjoyable and you've inspired millions all over the world! Take care and keep doing great things! - Mitchell
Thank you Professor for mentioning my video. For those who have hard time to find my video, just type in the search on RUclips: "Video answer to professor Walter Lewin", and you will find it. Yes my English is not the best - that is because I learned it myself... well somehow. Greetings from Croatia. Milan Karakaš.
Prof. what about the value of min time to transfer the liquid? Here for one bottle the liquid leaves and the same amount of volume is occupied by air from the other bottle if not then vacuum creates pressure diff now for maximum rate of transfer the volume of substance entering and the volume of substance leaving must be the same hence max rate of transfer is obtained when the cross-section available for water to leave and air to enter are same. So for the straw solution if you have a straw such that the inner cross section of the straw is same as the difference in the cross section areas of the connection and the straw you will have max. transfer rate. But the rate can still be increased if additional force is applied on water such as accelerating the setup upwards or having extra systems inside such as piston(plunger).
And it's such a beautiful solution! Thank you for taking the time to create and share these problems and solutions. Your enthusiasm is infectious. Thank you sir, I look forward to your next one.
I love these problems, whether or not they are on the web doesn't bother me because I will not spoil the solution for myself either way! Thank you Mr. Lewin for brightening up my days with such great lectures and cool problems you have posted. Thank you and have a wonderful day!
i remember seeing this vortex solution from playing around as a preschooler, science is incredible you can use it and be in awe of it no matter what age you are.
First! Love you and your lectures and awesome physics videos Professor Lewin! thank you so much for making them available to everyone online. You're an amazing teacher and thank you for spending you're hard work at MIT! You're part of why MIT is MIT you instill passion and creativity in your students and have taught so many amazing scholars and have given them the knowledge they need to know to change the world! And you're lectures are behind that! I am still in high school and MIT is my passion and hope to attend there one day! Thank you so much for everything you have done and continue to do professor!
The reason we ADORE you, is your absolute intelligence, your obvious curiosity, and like they say, if you understand it, you should be able to explaun it to a 2 year old, you tick all those bixes!! mund the lazy spelling.
I did not realize adults could be unaware of this basic principle of our reality. I hope this does not make me seem arrogant though it may, but I believe my generation has far more information exposure and hence we are able to accumulate a broader knowledge base on the principles of our reality. Often my friends and I will wax philosophical about the time like infinite nature of the cosmic foam that our reality bubbles up from, these concepts are at the cutting edge of what we know and understand, to see adults grasping a basic concept like air pressure would be met with sympathy that i am almost 100% sure would be mistaken for condescension. I do not think they are stupid i just believe they have been left behind, Thank you professor for trying to bring them up to speed.
I have learned much from watching your lectures and your videos . weather or not you can find solutions online I enjoy when you post problems to figure out because I wouldn't even think about these problems . I hope you keep posting these problems I certainly enjoy them .
i think posting some problems that their solutions are on the web is also helpful. people may blow their minds before looking for the solution or wait for you professor to post it while others may look for it directly but both of them have learned. looking forward to think of your next problem.
Prof. today i had received my order from amazon , its nothing but yours book ' for the love of physics..' i have just finished the introduction part.. and also i saw your video named "how to make teaching come alive in 1997 i hope so.. it was so brilliant .. And i am really happy and really really thank god to introduce me to your video.. My first video that introduced me to you was ur home lecturing about moment of inertia.. Then after with curiosity and love with science i was digging every videos of yours ... God bless you Prof.
I hadn't thought about that, i thought that a hole in the top would have done the job. Very interesting. Thanks a lot professor and, looking on the web kill all the fun. I wish you could do more videos like these they are very educational. Thank you again professor.
I always wondered why a vortex won't form automatically when you empty a bottle, but when you empty your bath or sink it automatically forms. Vertasium and SmarterEveryDay made an excellent video explaining this with a wonderful experiment showing why the earth's rotation has a bigger effect on a body of water covering a bigger surface area.
I took the initiative and be discipline to study physics through your lectures. I don't need to as I'm only 16 but I believe that you have gave me a hobby, to study physics. Thank you Walter Lewin, we are still friends. :)
Let's say it this way :D Those who wants to cheat... let them cheat! Me personally love these challenges and if you post a broblem I and many many others will understand the fun part of it and we really try to get it and make our own solution! There really is not need to go to check the ansfer elsewhere because the fun part really is to wait youre correct ansfer video!!! This is fun!! :)
Hey professor, hello from Brazil !! I've watched your video which you was talking about stop making these kind of videos (physics problems) , I hope you have changed your mind, I'm aways learning something new with them, I really appreciate the time you spend with us doing these physics problems,anyway, thank you professor, I love your videos,and I'm a big admirer of you. Keep it up =)
thank you very much for your awesome and interesting videos! its inspiring to watch you creating web content for the future generations helping them to understand the world and the laws of physics even better! thanks for all your hard work and your passion. you are definately one of the most inspiring persons on this planet!
Loved the video. I liked the pace. I really appreciated the vortex, I thought I knew what I was going to see, but it was more gorgeous than what I anticipated. I eagerly await any video you decide to put out. We're still friends. :)
I liked u r teaching because try to create a relationship between theory and practical which give good idea about its implementation which help in solving real life situation
things I've learnt today . 1. Jesus is always the answer 2. Spinning is also the answer if Jesus is not. And yes sir I never search anything on the web about any Problem you post it's because it takes the fun away if i don't think and simply Find the answer with no effort. And as always You're awesome professor :D
I like this profesor. Teach me with more practice than a lot of theory and formulas(i know same time need theory but need to see the efect visualization) Thank you. The Vortex,Sound(vibration) and inercia can solve the problem of gravitational spaceship? or Launch-ship(because no element in to the space to make vibration) I say sound vibration because i see same video where with the sound you can control drops of water in the air.
this usage of uncover has been done on purpose, of course i love what you mean when you said, what matters is not what you cover, what matters is what you uncoer in a introductory video to 8.02..Turkey awaits, if you ever like to visit, i would be glad to have the honour to tell you a bit about our country andand istanbul..
Hello walter, i don't often comment, but i thought this was worth while, i like your videos they are inspirational, I replicate them and try thrm with my little brother he is amazed, I remember the first time seeing a video with, the pendulum swing, to me a video doesn't need to be a solveable problem, just a fun experiment, the coolest ofcourse is if they are replicable at home or in the garden, son't be discouraged by comments or lack of enthusiasm, you are still inspiring, and I hope keep making videos
hi profesor! I have a problem idea for you! its to find the center of mass of a broom (for example). It can be done by many methods but the tricky and easy answer its to do it with your fingers and your arms extended up front, brom on top, fingers in the edges, and then move your fingers together... the finger will stop and be touching in the center of mass !! I hope you reply if youre interested so I can send you a video of the experiment, its real cool and simple and it would be better if you do the answer, demostration and then ask for the explanation in comments! Nice day evening or nigth depending on when you see this if so.. :)
In this video, you talked about a situation *when* *the* *lemonade* *suddenly* *stops* *falling* *down* *and* *opposes* *gravity* .............. I then saw the video in which you taped the problem, and there you made us see that the lemonade had suddenly stopped falling down but then it again started falling down as you shaked it a bit......... The reason which first came to my mind was that it was only occurring when most of the lemonade had flown to the other side....................and we already know that pressure at the bottom of the vessel will be equal to the sum of atmospheric pressure and the hydrostatic pressure of the liquid.........so if less liquid remains so hydrostatic pressure will reduce and so pressure at the lower bottle will reduce and hence pressure differential will be small so the air will not be too eager to go from bottom of the lower bottle to the top of the upper bottle and so we'll see fewer air bubbles forming and instead water should go down at a faster rate............. *and* *it* *is* *consistent* *with* *our* *daily* *experiences* ........(when we empty a filled bottle vertically into an another bottle......then it initially goes very slowly but right at the end as the process is just about to end, suddenly the liquid goes down all of a sudden..........) but you said that surface tension may come into play.............. so I then thought that surface tension is due to unbalanced forces at the uppermost layer of liquid (the molecules at the upper layer are more tightly packed so they form a sort-of-layer )............... *I* *LOOKED* *UP* *ON* *THE* *WEB* ......to find information regarding surface tension in lemonade..................... *I* *came* *to* *the* *conclusion* *that* *adhesion* *forces* *between* *the* *lemonade* *and* *the* *plastic* *bottle* *will* *be* *larger* *than* *the* *cohesion* *forces* *in* *between* *the* *molecules* *of* *lemonade* ............. so initially when the bulk of the lemonade is falling, then we know that bulk of a liquid will have nothing to do with surface tension and so *gravity* overpowers and so liquid keeps falling......................... But as we reach the business end, ie. when most of the liquid has flown down, *surface* *tension* *takes* *over* ........the adhesive forces take over and gravity is left wondering........... and then when you shake the bottle then you basically cause a mayhem at the molecular level, *no* *pun* *implied* .......the molecules of liquid move chaotically and hence in the process breaking the bonds formed between the molecules of liquid and bottle and so adhesion goes out of the window and again gravity takes over!!
>>>>> I came to the conclusion that adhesion forces between the lemonade and the plastic bottle will be larger than the cohesion forces in between the molecules of lemonade ..>>>> that is correct www.boundless.com/biology/textbooks/boundless-biology-textbook/the-chemical-foundation-of-life-2/water-51/water-s-cohesive-and-adhesive-properties-286-11419/
wow, interesting. half way through the video I've came out with something of my own: adding 2 tubes into the design, where one starts at the bottom (on the side of the bottle) and the other end is attached to the top of the other bottle, do the same on the other one. Allowing air from one bottle to escape quicker to the other. I believe it would work. then I've seen the tornado ... wow I did not expect that :D very good.
Wow! I had the idea that rotating the liquid would be the solution, but I didn't know that you only have to rotate it once and that the vortex then stays intact automatically.
oh.. awesome solution what i was trying is to put a pipe whose diameter is less than that of diameter of bottle...(say d=0.3D) so i would take one empty bottle (say bottle A) and stick a pipe by tape or glue on pipe such that a good length of pipe is outside the bottle.(note that if the height of liquid in the bottle is L(say) then the pipe should be >=2L and in every bottle the section of pipe should be >=L).then i would fill lemonade in bottle B and, i will then put the hanging section of pipe of bottle A the section will be >=L in the lemonade bottle and then i will screw the bottle (that hanging ). now because in both the bottle the pipe is of sufficient length >=L in each the pressure will be maintained through pipe. as technically they are two bottles but due to open pipe ending they have become one with two compartments. so pipe will make the two compartments in same pressure as the volume changes. so i think the lemonade will transfer fastest..... Sir please do reply about the solution and flaw in it if any. and please don't stop making videos even if the solution are available on web i never check it as i have to sharp my brain and hence why should i copy.. even after your solution i try to find something completely different as new methods are always there in the nature you just need to run your brain creatively... please continue sending problems doesn't matter if solutions are over web few people do not see the solution cause they are real people out there who love physics.. as rightly titled THEY WILL MAKE YOU LOVE PHYSICS
Hello Professor, I have been so fascinated because of your lecturing and I was wanting to prompt u about this, Are u watching the all new show in Nat Geo : Genius.. about your old friend Einstein.. Its really amazing.
Hi Professor! The world still have some physics problems what no one can explain for sure, but can give opinions, and I will be so glad to know what are your problems and opinions! Some of then are the dimensions of the universe, the universe itself, the polygon's math etc... Common ppl, give us more ideas! tkx!
But but but..... The pressure change does work. Alternately squeezing the bottles will create a pump. I believe it to be even faster than the vortex. I should make a video proving my hypothesis. I will get back on this.
I have a question, why is it that the vortex doesn't stop, yet it almost seems to speed up as it forms? Is it gravity that keeps the momentum going? or is it another force at work? Keep up the awesome videos, i love watching!
I have "seen" lads in Ireland who want to drink faster put a slinky straw in the bottle and hold it over the top to vent the air out when the bottle is inverted it works too.
Professor! I figured the solution by creating a vortex when I was cleaning my toilet... :) Glad to see it was correct. Please don't stop blowing my mind. Thank you so much
hehe the physics is everywhere
physics saved your toilet
don't be happy this much . i found this when i was 12 and my Geography teacher asked us to make a tornado simulation
So you are saying you are greater than the great mman Walter Lewin himself? Haha highly improbable
i also discovered this when i was 12 or 13 as i had to empty milk P.E.T.s in in 5l pot and had to do it preferably fast an without splashing i'm not saying that i'm smarter than anybody just i feel like if you are aware of your surroundings than is easy to figure out many physics problems
Love these video's! You don't need to limit yourself to things that haven't been "answered" on the internet, your way of demonstrating and explaining the problems is great. Keep them coming.
:)
When watching the video where you posed this question, I had the intuition to spin it... Surprised that this was the answer!! I guess it's something we see very often, emptying a filled sink starts by bubbling but then evolves to a less resistive mechanism by introducing a spin. Thanks for this video.
Thank you so much professor. I am a student from the University of Florida, but I truly learned Physics though your 8.01 and 8.02 lectures. I always think of you as one of my best professors who helped me realize Physics is very beautiful.
:)
I remember when I started to study physics in 2010 with my girlfriend. Almost everyday when we came home from the university (University of Helsinki, Finland), we used to watch your lecture about the subject we just learned. And that helped a lot! Although the lectures in our university are very high quality, your lectures are superior!
Your teaching style is very clear, entertaining and the demonstrations... They are just wonderful!
Actually a few of my friends, who didn't like physics before, became interested in physics because I showed them your lectures.
I'm so greatful to you (and I think I'm not the only one)! Thanks for all you've done to help people, not only to understand, but also to ❤️ physics!
thanks William for your kind words
My mother challenged me and my brother with this vortex method about 50 years ago. I have no idea where she got it. I was doing pretty well by shaking up and down to allow air a more free way up, but her vortex was more consistent. By then I had already some background of physics and understood what was happening, I have used it to my advantage ever since. I found your lecture videos recently and have greatly enjoyed them. Some of them are refreshment courses for me, but your presentation is always unique and exciting. I hope you don't quit your presentations any time soon, no matter any reduction in viewer numbers!
:)
Hello Professor Lewin! I am a student who is currently attending the University of Missouri Science & Technology. My goal is to graduate with a major in computer and electrical engineering. I wanted to let you know that I am one (among the millions of others) who has gained a lot of incredible knowledge by watching your lectures on RUclips. It started out with me needing some help in my first Physics class a few years ago and now I find myself watching your videos all of the time just for entertainment! You are an amazing professor and I would be honored to meet you some day. Even if you do not read this, I just wanted to say thank you for everything you've done. You make learning exciting and enjoyable and you've inspired millions all over the world! Take care and keep doing great things!
- Mitchell
I read all msgs. :)
Thank you Professor for mentioning my video. For those who have hard time to find my video, just type in the search on RUclips: "Video answer to professor Walter Lewin", and you will find it. Yes my English is not the best - that is because I learned it myself... well somehow. Greetings from Croatia. Milan Karakaš.
:)
Prof. what about the value of min time to transfer the liquid? Here for one bottle the liquid leaves and the same amount of volume is occupied by air from the other bottle if not then vacuum creates pressure diff now for maximum rate of transfer the volume of substance entering and the volume of substance leaving must be the same hence max rate of transfer is obtained when the cross-section available for water to leave and air to enter are same. So for the straw solution if you have a straw such that the inner cross section of the straw is same as the difference in the cross section areas of the connection and the straw you will have max. transfer rate. But the rate can still be increased if additional force is applied on water such as accelerating the setup upwards or having extra systems inside such as piston(plunger).
And it's such a beautiful solution!
Thank you for taking the time to create and share these problems and solutions. Your enthusiasm is infectious.
Thank you sir, I look forward to your next one.
:)
I love these problems, whether or not they are on the web doesn't bother me because I will not spoil the solution for myself either way! Thank you Mr. Lewin for brightening up my days with such great lectures and cool problems you have posted. Thank you and have a wonderful day!
I had done this in the past by accident but never realized it was faster. Cool video
Even though the solutions can be found on the Internet, it's really nice to watch your videos with given problems and explanations.
i remember seeing this vortex solution from playing around as a preschooler, science is incredible you can use it and be in awe of it no matter what age you are.
:)
First! Love you and your lectures and awesome physics videos Professor Lewin! thank you so much for making them available to everyone online. You're an amazing teacher and thank you for spending you're hard work at MIT! You're part of why MIT is MIT you instill passion and creativity in your students and have taught so many amazing scholars and have given them the knowledge they need to know to change the world! And you're lectures are behind that! I am still in high school and MIT is my passion and hope to attend there one day! Thank you so much for everything you have done and continue to do professor!
thanks for your kind words
:)
+Lectures by Walter Lewin. They will make you ♥ Physics. I am from India and I find ur the only one who makes sense while teaching physics
Comment approved. :)
:)
The reason we ADORE you, is your absolute intelligence, your obvious curiosity, and like they say, if you understand it, you should be able to explaun it to a 2 year old, you tick all those bixes!! mund the lazy spelling.
I did not realize adults could be unaware of this basic principle of our reality.
I hope this does not make me seem arrogant though it may, but I believe my generation has far more information exposure and hence we are able to accumulate a broader knowledge base on the principles of our reality.
Often my friends and I will wax philosophical about the time like infinite nature of the cosmic foam that our reality bubbles up from, these concepts are at the cutting edge of what we know and understand, to see adults grasping a basic concept like air pressure would be met with sympathy that i am almost 100% sure would be mistaken for condescension.
I do not think they are stupid i just believe they have been left behind, Thank you professor for trying to bring them up to speed.
It's even twice the best solution, it's not only faster, it's also a great pleasure to watch it :3
I have learned much from watching your lectures and your videos . weather or not you can find solutions online I enjoy when you post problems to figure out because I wouldn't even think about these problems . I hope you keep posting these problems I certainly enjoy them .
i think posting some problems that their solutions are on the web is also helpful. people may blow their minds before looking for the solution or wait for you professor to post it while others may look for it directly but both of them have learned. looking forward to think of your next problem.
Prof. today i had received my order from amazon , its nothing but yours book ' for the love of physics..' i have just finished the introduction part.. and also i saw your video named "how to make teaching come alive in 1997 i hope so.. it was so brilliant .. And i am really happy and really really thank god to introduce me to your video.. My first video that introduced me to you was ur home lecturing about moment of inertia.. Then after with curiosity and love with science i was digging every videos of yours ... God bless you Prof.
:)
What a pleasure to watch new videos from you almost everyday, sir. How lucky I am!!
I'm moved by your passion for Physics!
Mind Blowing!
:)
I hadn't thought about that, i thought that a hole in the top would have done the job. Very interesting. Thanks a lot professor and, looking on the web kill all the fun. I wish you could do more videos like these they are very educational. Thank you again professor.
I always wondered why a vortex won't form automatically when you empty a bottle, but when you empty your bath or sink it automatically forms. Vertasium and SmarterEveryDay made an excellent video explaining this with a wonderful experiment showing why the earth's rotation has a bigger effect on a body of water covering a bigger surface area.
:)
Because the engineers who designed your bath and sink had already known this?
Even though I knew it .. it won't stop me from watching you teaching it
教授你好。Amazing video! I'm learning your course in China
Hello chinese
I am very envy of the professor, he enjoyed his retirement with physics games. I love him!
I've seen many of your lectures! Physics is a beautiful thing! Thank you for sharing this with us! :D
:)
Wow as a fluid mechanist I am amazed by your intuition.
you are the reason why I chose to study physics over medicine. keep up the good work Doctor
:)
I took the initiative and be discipline to study physics through your lectures. I don't need to as I'm only 16 but I believe that you have gave me a hobby, to study physics. Thank you Walter Lewin, we are still friends. :)
:)
Let's say it this way :D
Those who wants to cheat... let them cheat!
Me personally love these challenges and if you post a broblem I and many many others will understand the fun part of it and we really try to get it and make our own solution!
There really is not need to go to check the ansfer elsewhere because the fun part really is to wait youre correct ansfer video!!!
This is fun!! :)
:)
I think I said that first on your problem video, and I was right! Thank you for still making videos ;-)!
Professor you are a really awesome teacher you are really clear in making every query's problem go away easily
I love this man. He looks so happy making this vortex
We are still friends! I love physics problems keep them coming professor!!! take good care!!
Thank you Prof. Lewin! You're an inspiration.
Hey professor, hello from Brazil !!
I've watched your video which you was talking about stop making these kind of videos (physics problems) , I hope you have changed your mind, I'm aways learning something new with them, I really appreciate the time you spend with us doing these physics problems,anyway, thank you professor, I love your videos,and I'm a big admirer of you.
Keep it up =)
:)
don't stop it !
we enjoy physics with you professor Walter
wow.... brilliant professor....and you are a very kind person...keep showing us the beauty of physics...thnk u so much
What a beautiful demonstration of Physics at work!
Awesome! Please don't stop posting problems
I enjoy your videos so much. I love your enthusiasm and spirit.
thank you very much for your awesome and interesting videos! its inspiring to watch you creating web content for the future generations helping them to understand the world and the laws of physics even better! thanks for all your hard work and your passion. you are definately one of the most inspiring persons on this planet!
Excellent.. 😊 This is how we can enjoy the thrill of physics.. Thank you sir for bringing this kind of problems.
Loved the video. I liked the pace. I really appreciated the vortex, I thought I knew what I was going to see, but it was more gorgeous than what I anticipated. I eagerly await any video you decide to put out. We're still friends. :)
I liked u r teaching because try to create a relationship between theory and practical which give good idea about its implementation which help in solving real life situation
Keep it up! You could be the next Doc Brown.
:)
he reminds me of the doctor from "back to the future" :)
:)
You are GREAT!! Thank you for all your videos!
Altijd een plezier om naar te kijken.
prima!
I've played with this toy back in 1998. Cool tornado maker, twists onto 2 Liter bottles like mountain Dew.
Wonderful professor Walter Lewin , you make physics work in world with your examples
:)
Such an elegant solution! Thank you professor.
things I've learnt today .
1. Jesus is always the answer
2. Spinning is also the answer if Jesus is not.
And yes sir I never search anything on the web about any Problem you post it's because it takes the fun away if i don't think and simply Find the answer with no effort. And as always You're awesome professor :D
Yes, of course, I should have mentioned that.
If Jesus is always the answer how can it not be a answer? You made a paradox there.
wanted to make an amusing back to the future comment.....then I started learning. Lemonade Vortex pro, thank you Proff :)
:)
Best science teacher ever
:)
I like this profesor. Teach me with more practice than a lot of theory and formulas(i know same time need theory but need to see the efect visualization) Thank you.
The Vortex,Sound(vibration) and inercia can solve the problem of gravitational spaceship? or Launch-ship(because no element in to the space to make vibration) I say sound vibration because i see same video where with the sound you can control drops of water in the air.
One day, i'll uncover something and name it after you my dear teacher! You are an honour to our species..
this usage of uncover has been done on purpose, of course i love what you mean when you said, what matters is not what you cover, what matters is what you uncoer in a introductory video to 8.02..Turkey awaits, if you ever like to visit, i would be glad to have the honour to tell you a bit about our country andand istanbul..
:)
I have lectured in Istanbul.
When was this?
I wish I had a professor like you during my school days..:)
:)
well done Walter. You are my inspiration
:)
Thank you sir for making my Day 💗 respect and prayers 🙏😉☺️💞👍 From Pakistan
I love your videos, please post more of them, they are wonderful. :)
Thank you Professor Walter Lewin.
Love your videos...keep it up 😄
Hello walter, i don't often comment, but i thought this was worth while, i like your videos they are inspirational, I replicate them and try thrm with my little brother he is amazed, I remember the first time seeing a video with, the pendulum swing, to me a video doesn't need to be a solveable problem, just a fun experiment, the coolest ofcourse is if they are replicable at home or in the garden, son't be discouraged by comments or lack of enthusiasm, you are still inspiring, and I hope keep making videos
:)
hi profesor! I have a problem idea for you!
its to find the center of mass of a broom (for example).
It can be done by many methods but the tricky and easy answer its to do it with your fingers and your arms extended up front, brom on top, fingers in the edges, and then move your fingers together... the finger will stop and be touching in the center of mass !!
I hope you reply if youre interested so I can send you a video of the experiment, its real cool and simple
and it would be better if you do the answer, demostration and then ask for the explanation in comments!
Nice day evening or nigth depending on when you see this if so.. :)
:)
YOU ARE A DAMN GENIUS, SIR....!!!
Nice lemonade and nice solution.
Very nice lesson! Thank you Professor Walter!
:)
Wow! This was a great problem. I really enjoyed this!😊❤
In this video, you talked about a situation *when* *the* *lemonade* *suddenly* *stops* *falling* *down* *and* *opposes*
*gravity* ..............
I then saw the video in which you taped the problem, and there you made us see that the lemonade had suddenly stopped falling down but then it again started falling down as you shaked it a bit.........
The reason which first came to my mind was that it was only occurring when most of the lemonade had flown to the other side....................and we already know that pressure at the bottom of the vessel will be equal to the sum of atmospheric pressure and the hydrostatic pressure of the liquid.........so if less liquid remains so hydrostatic pressure will reduce and so pressure at the lower bottle will reduce and hence pressure differential will be small so the air will not be too eager to go from bottom of the lower bottle to the top of the upper bottle and so we'll see fewer air bubbles forming and instead water should go down at a faster rate.............
*and* *it* *is* *consistent* *with* *our* *daily* *experiences* ........(when we empty a filled bottle vertically into an another bottle......then it initially goes very slowly but right at the end as the process is just about to end, suddenly the liquid goes down all of a sudden..........)
but you said that surface tension may come into play..............
so I then thought that surface tension is due to unbalanced forces at the uppermost layer of liquid (the molecules at the upper layer are more tightly packed so they form a sort-of-layer )...............
*I* *LOOKED* *UP* *ON* *THE* *WEB* ......to find information regarding surface tension in lemonade..................... *I* *came* *to* *the* *conclusion* *that* *adhesion* *forces* *between* *the* *lemonade* *and* *the* *plastic* *bottle* *will* *be* *larger* *than* *the* *cohesion* *forces* *in* *between* *the* *molecules* *of* *lemonade* .............
so initially when the bulk of the lemonade is falling, then we know that bulk of a liquid will have nothing to do with surface tension and so *gravity* overpowers and so liquid keeps falling.........................
But as we reach the business end, ie. when most of the liquid has flown down, *surface* *tension* *takes* *over* ........the adhesive forces take over and gravity is left wondering...........
and then when you shake the bottle then you basically cause a mayhem at the molecular level, *no* *pun* *implied* .......the molecules of liquid move chaotically and hence in the process breaking the bonds formed between the molecules of liquid and bottle and so adhesion goes out of the window and again gravity takes over!!
>>>>> I came to the conclusion that adhesion forces between the lemonade and the plastic bottle will be larger than the cohesion forces in between the molecules of lemonade ..>>>>
that is correct
www.boundless.com/biology/textbooks/boundless-biology-textbook/the-chemical-foundation-of-life-2/water-51/water-s-cohesive-and-adhesive-properties-286-11419/
That was so cool!! This video made me very interested in physics now
this man is amazing
Thanks for Explanation 🇮🇳💖
wow, interesting.
half way through the video I've came out with something of my own:
adding 2 tubes into the design, where one starts at the bottom (on the side of the bottle) and the other end is attached to the top of the other bottle, do the same on the other one. Allowing air from one bottle to escape quicker to the other. I believe it would work.
then I've seen the tornado ... wow I did not expect that :D very good.
thank you !! we have to touch your feet for things you are doing for us at this age ! physics 👍
you can put air hoses between the 2 sides one high one low
@@SimonWoodburyForget Creating pressure/suction also requires energy, not to mention it can deform the bottle.
Congratulations to your 100.000 subsribers :D
thank u
ma shaa Allah ..i like this man's physics lessons
Professor!.... Love your videos...keep it up
:)
Wow! I had the idea that rotating the liquid would be the solution, but I didn't know that you only have to rotate it once and that the vortex then stays intact automatically.
learned this in grade 1 many years ago, it's a neat trick
you are awesome professor .... thanks for the problems
thats some strength that you got there🍾
oh.. awesome solution what i was trying is to put a pipe whose diameter is less than that of diameter of bottle...(say d=0.3D)
so i would take one empty bottle (say bottle A) and stick a pipe by tape or glue on pipe such that a good length of pipe is outside the bottle.(note that if the height of liquid in the bottle is L(say) then the pipe should be >=2L and in every bottle the section of pipe should be >=L).then i would fill lemonade in bottle B and, i will then put the hanging section of pipe of bottle A the section will be >=L in the lemonade bottle and then i will screw the bottle (that hanging ).
now because in both the bottle the pipe is of sufficient length >=L in each the pressure will be maintained through pipe. as technically they are two bottles but due to open pipe ending they have become one with two compartments. so pipe will make the two compartments in same pressure as the volume changes. so i think the lemonade will transfer fastest.....
Sir please do reply about the solution and flaw in it if any. and please don't stop making videos even if the solution are available on web i never check it as i have to sharp my brain and hence why should i copy.. even after your solution i try to find something completely different as new methods are always there in the nature you just need to run your brain creatively...
please continue sending problems doesn't matter if solutions are over web few people do not see the solution cause they are real people out there who love physics..
as rightly titled THEY WILL MAKE YOU LOVE PHYSICS
try it and let me know
Hello Professor, I have been so fascinated because of your lecturing and I was wanting to prompt u about this, Are u watching the all new show in Nat Geo : Genius.. about your old friend Einstein.. Its really amazing.
:)
dont worry about web solutions.. we love trying to figure it out ourselves
it was amazing proffessor....😀
awesome explanation of lemonade problem thanks sir .
thanks for this great advice this will help draining water
thanks professor for making physics so easy and fantastic
Hi Professor! The world still have some physics problems what no one can explain for sure, but can give opinions, and I will be so glad to know what are your problems and opinions! Some of then are the dimensions of the universe, the universe itself, the polygon's math etc... Common ppl, give us more ideas! tkx!
Jippie ik had t goed ! Bedankt Walter.......... Spreek je later weer vriend !
ja je had het goed
very exciting to see you do an experiment
:)
But but but..... The pressure change does work. Alternately squeezing the bottles will create a pump. I believe it to be even faster than the vortex. I should make a video proving my hypothesis. I will get back on this.
I have a question, why is it that the vortex doesn't stop, yet it almost seems to speed up as it forms? Is it gravity that keeps the momentum going? or is it another force at work?
Keep up the awesome videos, i love watching!
use google
excellent....enjoy your videos....I have watched your MIT lectures and enjoy those also.
I have "seen" lads in Ireland who want to drink faster put a slinky straw in the bottle and hold it over the top to vent the air out when the bottle is inverted it works too.
:)
Congrats to 100k