How to Make Teaching Come Alive - Walter Lewin - June 24, 1997

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  • Опубликовано: 14 мар 2015
  • Talk given by Prof. Lewin almost every year between 1996 and 2004 during the summer vacation for Science Teachers. This recording is from 1997. He discussed how to uncover the beauty of physics to students. He discusses the perception of seeing color and showed colors by using only black and white slides (the famous Edwin Land demo). He also covered (and demonstrated) Rayleigh Scattering which makes the sky blue and sunsets red. By holding cigaret smoke in his lungs he demonstrated why clouds are white.He uncovers the Physics of Rainbows and creates a rainbow during his lectures and he demonstrates (as he earlier arrived) that the rainbows are nearly 100% linearly polarized.
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Комментарии • 750

  • @thesafteycrazycuber
    @thesafteycrazycuber 8 лет назад +155

    I found your lectures about two years ago sir Lewin and I must say I adore them so numerous and easy lectures to understand

  • @nobodyyouknow9839
    @nobodyyouknow9839 4 года назад +17

    This the best way to utilize your time by wacthing your lectures

  • @davidbrayton1143
    @davidbrayton1143 4 года назад +13

    If they handed out Oscars for physics lectures, he’d win another one for that lecture. Really, a phenomenal presentation in every way. He’d probably win a technical achievement award too for that magic chalk.

  • @vjohnification
    @vjohnification 4 года назад +8

    Amazing professor! Every time I see his lectures, he thrills me.

  • @EvaTruve
    @EvaTruve 2 года назад +4

    "Knowledge adds and never subtracts." At difficult times it's something that cant be taken away from you.

  • @MO-em6ex
    @MO-em6ex 4 года назад +2

    Good to follow and understand! Love Physics like this! You can see that he‘s living the stuff he‘s teaching! That’s incredible!!! Thank‘s for this Video!

  • @foxvulpes8245
    @foxvulpes8245 4 года назад +152

    "You all look at rainbows, but most of you have never seen them"
    I spend a lot of time trying to see...

    • @Reylarian
      @Reylarian 4 года назад +4

      its a circle, not a bow.

    • @knowledge.facts532
      @knowledge.facts532 4 года назад +2

      Spray water using your thumb on wall in a sunny day ,you can see rainbow .

    • @pinklady7184
      @pinklady7184 4 года назад +1

      You see lots of rainbows in wet countries as here in Ireland. They emerge usually after the rain stops: loose water molecules in air create rainbows with the rays of sun emitting colours. Sometimes, you see double rainbows. Triple rainbows are extremely rare. Whenever I see rainbows, I know they always point in the exact opposite directions of the sun.

    • @firstnamelastname4997
      @firstnamelastname4997 4 года назад

      His rainbows. It's a subjective phrase. Prepare to see his rainbows. Not other rainbows. He doesn't know about those rainbows. But them, he has a relationship with them. Not the stranger rainbows of your past. Spend more time listening. Try to listen. Be paranoid.

    • @error.418
      @error.418 4 года назад

      @@firstnamelastname4997 "Be paranoid." 😂I hope you mean skeptical, inquisitive.

  • @popsynthyarby5055
    @popsynthyarby5055 6 лет назад +20

    I could not believe that when I moved my polarized sunglasses over the screen I saw that the smoke was really polarized! Then it occurred to me that ALL of my monitor's light was polarized. Thank you for the masterful teaching.

    • @MartinVerkest
      @MartinVerkest 2 года назад

      with a rotatable polarizing filter (to camera lenses for instance - can be used on a 'naked eye' too..., ), it is possible to look 'into' the water (removing the flickering....or add...just attempt/try), standard photography knowledge.

  • @TheMTBChannel
    @TheMTBChannel 4 года назад +2

    Thanks Walter. I'm 56 and have done physics and engineering along the way and learnt a few things from this. Always a good day when you learn one thing let alone more. Thanks again.

  • @Ryzen_56X
    @Ryzen_56X 7 лет назад +203

    In high school I was a very bad student, I had to take night school to graduate, for some reason I did not find academic knowledge or school interesting or amusing at that time .... years have past for me and I found out the reason of my poor academic performance at that time, the school method of teaching lacked creativity to reach and awake my interest towards it. I discovered your videos at the beginning of this year and got hooked up immediately with them ... guess what ? I started college this fall in Aerospace engineering because I find your teachings easy to understand and learn every lecture in your videos got very clear to me and easy to understand, I've watched them all. Thank you for posting your lectures, for people like me you have helped me bring back my confidence in learning and achieving my goals.
    As an advice for those kids who had a bad academic performance and lack confidence in continuing studying ... DON'T GIVE UP, is never too late to restart and continue your goals.

    • @lecturesbywalterlewin.they9259
      @lecturesbywalterlewin.they9259  7 лет назад +48

      Very nice!

    • @wong2b
      @wong2b 5 лет назад +18

      I couldn't agree more. It is never too late, I got my BS in Electrical Engineering at the age of 45 with a GPA of 3.85 and I barely made it through high school. I guess it took 27 years to learn how to be a student.

    • @rigdigwus
      @rigdigwus 4 года назад +2

      not it is because you didnt care about it as a kid but now you realise it actually is quite interesting

    • @AlienRelics
      @AlienRelics 4 года назад +3

      Almost all of what I know about physics and electronics, I learned on my own.

    • @AkamiChannel
      @AkamiChannel 4 года назад

      Ogeid Zepol Dr. Physics A is also nice

  • @youngbloodbear9662
    @youngbloodbear9662 7 лет назад +42

    Mr. Lewin, I've known about your lectures and enjoyed them since I was about 10, now that I'm in highschool and have an understanding of algebra and such, I've been able to begin going through your lectures and actually appreciating the impeccable fluidity your lectures have and how clear you are able to demonstrate the topics of 8.01-8.03.... It really is amazing. I'm on track to go to MIT or similar, all honors or AP classes, but it's almost not worth it with you gone... I lament that I can't be a student of your's but you have my respect and my thanks.

  • @AhmadHddad01
    @AhmadHddad01 6 лет назад +11

    I really wish that i was in your class someday.
    Ur great man professor.

  • @mistertornado2303
    @mistertornado2303 3 года назад +3

    Professor, I first found out about you when I watched a video on RUclips years ago called "Professor Beats Student". I have since watched nearly all of your lectures that have been made public and thoroughly enjoy how you engage your students and your philosophy of teaching. You are an inspiration to me, a fellow educator, and you truly make physics fun and enthralling for everyone. As a Christian, I see everything as the manifestation of the glory of God in His creation - and I'm aware that you're an atheist and do not perceive it like I do. However, the way that you convey these topics, makes me more in awe of what God has done. So thank you, Professor.

  • @shubhkarmansingh1641
    @shubhkarmansingh1641 3 года назад

    Really you are the best physics teacher ever i have seen. Such a knowledgable person. The way you make things clear is awsome. If i get a chance to meet you i will be really fortunate

  • @rishavkumar9509
    @rishavkumar9509 3 года назад +1

    When ever I found found your video in my recommendation I just start watching like a TV serial ....this is interesting. Thank you so much sir

  • @homeryura
    @homeryura 7 лет назад +2

    Your lectures are most interesting, most spectacular and easy to get at the same time!

  • @afterthesmash
    @afterthesmash 4 года назад +63

    When I play with my RUclips playback rate, the colors do change a bit for different playback speeds.

    • @olalidehorn8291
      @olalidehorn8291 4 года назад +2

      1,75 x normal speed, the spinning wheel is working!

  • @RakibulIslam-yz3gn
    @RakibulIslam-yz3gn 8 лет назад +14

    Professor Lewin, I LOVE your lectures so much! They are so interesting, informative and easy! :D

  • @mariocesarsousa
    @mariocesarsousa 9 лет назад

    Awesome. The power of teaching comes from the love for doing it.

  • @betascire2607
    @betascire2607 4 года назад

    I really love his teaching style.

  • @therealzilch
    @therealzilch 4 года назад +1

    Wonderfully informative and entertaining. Science teaching at its best.

  • @user-be4yc2vr5c
    @user-be4yc2vr5c 4 года назад

    I recommend all your courses; and your teachings on physics and the like that have been offered for free via youtube(even if youtube themselves suck lol) have been an invaluable resource to me in life. Thank you. Truly. If I was forced to try to participate in the slave making "education" system to get this and not the comfort of my own home with zero pressures for free I would have missed out beyond what I care to even imagine. I truly see the world differently now and my love for science, inventing, teaching, and free independent learning has exploded.

  • @pepineric
    @pepineric 7 лет назад

    definitely one of the best, all my respect Mr Lewin

  • @happyscience8962
    @happyscience8962 7 лет назад +4

    Actually Great lecture. I didn't love physics before watch his lectures.Thank you so much..He is greatest..Now I love all sciences..I proud to say reason is Prof.Walter Lewin..

  • @uendimusta3215
    @uendimusta3215 4 года назад +2

    This is the kind of teacher every school needs

  • @vivek4991
    @vivek4991 4 года назад +15

    I have an exam of digital signal and processing tomorrow and here I am at midnight learning about colours.

  • @miguelangelsimonfernandez5498
    @miguelangelsimonfernandez5498 7 лет назад

    This evening I remembered this very talk of yours with a friend who is an experienced ophtalmologist. She was exhausted after a congress that tool place this weekend in Madrid, Spain. We were talking about the neurophisiology of sight she told me that western Sahara tribesmen (today more or less extinct) only see three or four colours, white, blue and sand mainly. No greens, for example. thank you once more for these beautiful and heart, or should I say brain, comforting lectures.

  • @bindujose2954
    @bindujose2954 4 года назад +2

    The channel's name is so appropriate. Your videos do really make us fall in love with physics.

  • @vijaychoudhari609
    @vijaychoudhari609 4 года назад +2

    Wonderful.....thanks to RUclips , I learn so much now sitting on the arm chair which I missed out about 55 years ago..... Thank you so much .....

    • @worklion50
      @worklion50 4 года назад

      Right there with ya...

  • @titi08
    @titi08 Год назад

    Thanks to you, I now have the explanation for rainbow. I'm very grateful.

  • @joshuataylor71
    @joshuataylor71 7 лет назад +2

    I loved this lecture!

  • @abhilashhazarika7790
    @abhilashhazarika7790 3 года назад

    Monday's my biology paper and IDK why I am watching this with my bio textbook opened....i guess there's something spellbound bout this man n his way of teaching....RESPECT to thee sir

  • @jcinaz
    @jcinaz 4 года назад +1

    Fantastic! Science has never been so interesting to me. I learned a lot.

  • @prabhakarrao4922
    @prabhakarrao4922 4 года назад

    A big hello from Auckland New Zealand. I taught physics to high school seniors way back in the 70s but your lecture presented here is really inspiring. I enjoyed those days. I too believed and practiced blending practical demonstrations whilst covering theory. It is an incredibly powerful way of reinforcing learning. Thank you very much.

  • @thomasweaver4791
    @thomasweaver4791 6 лет назад

    the ultimate showman and teacher. Stay healthy and happy,

  • @nashgujjalu104
    @nashgujjalu104 2 года назад

    What a wonderful lecture! Thank you professor.

  • @sathiyamoorthydakshinamoor1736
    @sathiyamoorthydakshinamoor1736 3 года назад

    Prof Walter Lewin is the best to teach Physics. Any one, irrespective of the educational background, can understand his lectures. MIT is the blessed Institute to have him. Thanks to RUclips to bring his lectures to all.

  • @LastMechanicsBender
    @LastMechanicsBender 4 года назад

    Very engaging lecture, really loved it!

  • @dirksaenen436
    @dirksaenen436 4 года назад

    Absolutely fabulous.
    Best way to spend the Covid-19 lockdown is to watch and rewatch the lectures !

    • @dirksaenen436
      @dirksaenen436 4 года назад

      on the other hand :
      damn Walter, rainbows will never look the same again.
      ;-)
      Thank you

  • @titusnelson9499
    @titusnelson9499 2 года назад

    Absolutely Fantastic. Just fantastic

  • @hassanhan9124
    @hassanhan9124 4 года назад

    Humor, science and the love of sharing knowledge; that's Mr Lewine. What Professor...!

  • @abhijitsingh734
    @abhijitsingh734 4 года назад +2

    Your lectures are so much easier to understand.....some times I thought that I m a Proffesor😅😅😅.....thnxxxx

  • @paulholzherr2993
    @paulholzherr2993 7 лет назад +8

    Great stuff! I like the way he creates the dotted lines with the chalk!

    • @lecturesbywalterlewin.they9259
      @lecturesbywalterlewin.they9259  7 лет назад +8

      ruclips.net/video/raurl4s0pjU/видео.html

    • @Anonymous_self
      @Anonymous_self 2 года назад

      @@lecturesbywalterlewin.they9259 I watched this video a day before yesterday. I hope you yourself enjoying too. 🤗

  • @AGhulam73985
    @AGhulam73985 7 лет назад +4

    Doing post grad degree in Economics and loving physics Because of Prof. Lewin ! Inspiration for teachers

  • @bitscorpion4687
    @bitscorpion4687 7 лет назад +1

    you are my favorite physics teacher !!!!!!!!
    i can understand many things i couldnt understand!

  • @SanjayPandit-sc9xx
    @SanjayPandit-sc9xx 2 месяца назад

    Most important lecture for me .Thank you sir .by best proffeser of the world (you).

  • @Ferndalien
    @Ferndalien 4 года назад

    I had to take 8.03 as a sophomore in 1973. Prof. Lewin lectured, and his lectures were filled with formulas and I could barely keep up taking notes and always at the end there was a demonstration that brought the formulas to life. Not just a great, engaging lecturer, but a brilliant lecturer.

    • @lecturesbywalterlewin.they9259
      @lecturesbywalterlewin.they9259  4 года назад

      wowwww so you were one of my students at MIT. My 8.03 lectures of 2004 ar now on my RUclips channel. I can assure you that they are much much better than my 8.03 lectures in 1973.

  • @MrRipsaw1
    @MrRipsaw1 4 года назад +10

    WOW!! 52 years old and I learnt lots that I thought I knew, however...
    Mystery 1: Why does the sun at sunset sometimes turn green just before the it vanishes behind the horizon?
    Mystery 2: Why is RUclips Recommendations making this video popular again in December 2019? (I'm glad it is)

  • @johnkendal8303
    @johnkendal8303 6 лет назад +1

    How lucky those students were, i hope they all appreciated their good fortune.

  • @kanalmatematika8498
    @kanalmatematika8498 2 года назад

    Prof Lewin, you're really Great. I'm very interested in your lectures.

  • @filebb1
    @filebb1 7 лет назад

    Best lecture of physics I have ever seen

  • @danadane9786
    @danadane9786 Год назад

    I love learning from you!

  • @ianmoone2463
    @ianmoone2463 4 года назад +4

    I really love this wonderful lecturer on how simplified his lectures were. And I really wonder for a long time now, how did he ever made that straight dotted line in just one stroke.

    • @Bunny_Aoife
      @Bunny_Aoife 4 года назад

      I read your comment before watching the video, and I thought I had seen quite a few professors do super straight lines, dotting at extreme speeds and the like... I thought I've seen it all, how impressive could this dotted line be... but holy shit, I wanna know how he does this... it was awesome.

    • @charlesclements4350
      @charlesclements4350 4 года назад +1

      Go back and look carefully at the way that he is holding the chalk. Notice that the chalk is flat on the end. The chalk grabs then skips as he drags it across the board.

    • @charlesclements4350
      @charlesclements4350 4 года назад

      Ian, look at the way he holds the chalk. It grabs then skips as he drags it across the board. Personally, I hate it because it set up a horrible vibration in the finger.

    • @faefesd4810
      @faefesd4810 4 года назад

      @@Bunny_Aoife there are 3 minute tutorials on yt

    • @tonydawson1760
      @tonydawson1760 4 года назад

      Yeh you can only see it when viewed from a 42 degree angle or somethin 🙈😷

  • @zaarakhan7678
    @zaarakhan7678 7 лет назад

    i never saw any teacher like him ...he is a great man and great teacher...i wish i can meet him

  • @grahambird1570
    @grahambird1570 4 года назад

    Fantastic Lecture !

  • @varatharajaperumal7909
    @varatharajaperumal7909 3 года назад

    Thanks God I found this channel

  • @jonathoncarter9817
    @jonathoncarter9817 7 лет назад

    I drink beer on Friday nights and watch Prof. Lewin's lectures. He's such an entertaining and understandable lecturer!

  • @stevelenores5637
    @stevelenores5637 4 года назад +86

    Paused video to confirm it goes back to black and white.

    • @stevelenores5637
      @stevelenores5637 4 года назад +6

      @Frank Heuvelman True enough, pausing is for doubters like me. That is what makes a scientist. Confirmation not faith.

    • @sanderd17
      @sanderd17 4 года назад +2

      I wondered whether the camera also picked up the effect. Apparently not. But I do see the colors in the reverse order as he tells them. Something to do with mirroring or refresh frequencies?

    • @RWBHere
      @RWBHere 4 года назад +2

      @@sanderd17 That's interesting, because I saw the colours as he described them, before he described them.
      And I paused the video to confirm that the effect is real.

    • @loupiotable
      @loupiotable 4 года назад +1

      @@RWBHere I've seen no color :(

    • @electricpaisy6045
      @electricpaisy6045 4 года назад

      It impressed me pretty much that this effect worked even on camera with the fps number and all that.

  • @banajadandasena4142
    @banajadandasena4142 4 года назад

    Wonderful explanation..

  • @juancarlosabad3298
    @juancarlosabad3298 7 лет назад

    ...amazing explanation of the rainbow physics....

  • @illumiNOTme326
    @illumiNOTme326 4 года назад +1

    Amazing professor

  • @rogergr5019
    @rogergr5019 3 года назад

    This man is from my hometown in the Netherlands. Love him

  • @AdminTuber
    @AdminTuber 6 лет назад

    The best teacher ever!

  • @wt_heck
    @wt_heck 4 года назад +1

    as a photographer this is amazing to know!

  • @jonnnymoose
    @jonnnymoose 4 года назад

    Just found this......superb. I now have a new view on hitchhikers guide to the galaxy.

  • @crystal6383
    @crystal6383 7 лет назад

    Amazing lecture, everyone should appreciate rainbow...

  • @uspsrinivasaditya
    @uspsrinivasaditya 4 года назад +1

    In my childhood I had a question in my mind whether rainbow is 2D or 3D! This video explained it all!

  • @brandonlawrence7896
    @brandonlawrence7896 4 года назад

    Walter I love your lectures

  • @just4callplus
    @just4callplus 4 года назад

    Very Great et super good Teaching, Thanks!

  • @MCRmechanic
    @MCRmechanic 7 лет назад +2

    He's so fast at angle calculation and expression. A true master and a pleasure to watch.

  • @wirsindhelden0
    @wirsindhelden0 2 года назад +1

    He's such a legend that I'll bet he just REALLY needed a cigarette break and managed to seamlessly work 4 of them into his lecture without anyone noticing 😂
    But in all seriousness - this man, is an absolute inspiration. Somehow, every video I watch is more intriguing than the last. I only wish I had found his videos sooner!

  • @dogscats8141
    @dogscats8141 5 месяцев назад

    My favorite teacher

  • @sujitmohanty1
    @sujitmohanty1 2 года назад

    What a lecturer!

  • @razaqalmarsoomi6757
    @razaqalmarsoomi6757 4 года назад

    Great lecture, thanks.

  • @marketmail49
    @marketmail49 Месяц назад

    I am so happy I could calculate the values of phi 😅. Thank you, Professor. You are always my "mentor".

  • @junaidkhan6329
    @junaidkhan6329 2 года назад

    I love you sir...i love your wat to teach physics..you give feel on physics.

    • @lecturesbywalterlewin.they9259
      @lecturesbywalterlewin.they9259  2 года назад +1

      Glad to hear that

    • @junaidkhan6329
      @junaidkhan6329 2 года назад

      @@lecturesbywalterlewin.they9259 sir iam also glad on your reply.. because you are the Best teacher...so please sir upload more and more videos of your lectures because iam a hunger to study physics with concept as well as with feel.....thank you sir....god bless you....

  • @SteveFrenchWoodNStuff
    @SteveFrenchWoodNStuff 7 лет назад

    Great lecture. I was surprised to see the color difference in the cigarette smoke demonstration.

  • @ashitbarank
    @ashitbarank 7 лет назад

    you are just that !! wonderful !!!

  • @wlan246
    @wlan246 4 года назад +10

    23:57 As a great philosopher once said, "If it ain't broke, you're not tryin'!"

  • @johankotze42
    @johankotze42 4 года назад +6

    Many years ago there was a julius Sumner Miller. (1970s?) He had a similar approach!

  • @pala_sh_arma
    @pala_sh_arma 4 года назад

    I have biology exam today ( in an engineering college). It's 4:40 am and here I am... just finished watching this.

  • @pramodjha8201
    @pramodjha8201 2 года назад

    Mr. Lewis is really Godly scholar & teacher. I would love to call him Mr. Physics. He makes Physics so loving.
    No doubt, he must have made thousands of Physics-lovers. Me included.
    God bless him,
    Pramod Narayan Jha
    B. Tech. 1970
    76. Retired mechanical design&project engineer ,
    Presently a Lychee farmer & a humble science teacher to poor & needy kids absolutely F. O. Cost

  • @user-it2ov6id2f
    @user-it2ov6id2f 4 года назад

    thank you very very much Sir

  • @kid_nero61
    @kid_nero61 4 года назад +9

    This dude really just smoked a cigarette to eagerly explain and demonstrate a complex concept of natural phenomenon in a lecture. Props.

  • @aakimowgli
    @aakimowgli 4 года назад

    Thank You sir Indian Youth loves you tremendously

  • @circleofstone3114
    @circleofstone3114 2 года назад

    I need to get ahold of this awesome mans book.

    • @lecturesbywalterlewin.they9259
      @lecturesbywalterlewin.they9259  2 года назад

      Before you decide to buy a book from me *I strongly suggest you get a free copy using the pdf file.*
      fiisikis.weebly.com/uploads/5/4/9/3/54939617/for_the_love_of_physics.pdf
      You should also consider to buy my book at amazon in your country. *I have been told that in India you can get my book from Amazon and Flipkart for $4.50* These books do not contain the 15 colored photo index (that's why they are so cheap); the pdf file does not include that either.
      If you can afford it, of course, I am willing to send you a signed copy of my book with *a special note for you + a signed picture of me, which will also have your name on it,* but the price is high as I pay 30% tax here in the US of your payment. Postage for me is also high (e.g., India $35). Ofcoz the book that I send you contains the photo index.
      Your total costs for 1 paperback copy: US $40; Europe, South America, Brazil, Canada, Pakistan, Nepal, Bangladesh Tanzania & India $65; Middle East & Asia: Japan, Philippines, China, Thailand & Australia $80. I make zero money on these sales, I sell them for what they cost me. You should transfer the money to my PayPal account (see below). *Since we are friends, please mark "family and friends", PayPal will then not charge me a 5% fee* and please let me also know in PayPal your name and complete address and *which name I should use for my note in your book and on my picture.*
      *For those of you who only want a signed copy of the picture of me, swinging from the pendulum,* with your name on it as well, it will cost you *$10 for 1 copy* (that includes postage). It's the same price for all countries. *You should send me on PayPal your complete address and the name you want me to write on the picture.* Please transfer the $12 to *my PayPal account which is* lewin-physics@physics.comcastbiz.net. *Keep in mind that you must first enter PayPal and then my account.*

  • @marceld6061
    @marceld6061 4 года назад

    This lecture should be MANDATORY in high school in Hawaii! The land of rainbows, blue skies and sunsets!

  • @simeydotme
    @simeydotme 4 года назад

    oh god i just learnt so much

  • @mathxnoob
    @mathxnoob 5 лет назад

    we are using this in a sense in surveying..

  • @electricpaisy6045
    @electricpaisy6045 4 года назад

    I love good lectures

  • @dfnuniverse2198
    @dfnuniverse2198 4 года назад

    OUTSTANDING!!! BRAVO!!! 👌🖤✅💪🏽👀

  • @round2hell15million3
    @round2hell15million3 3 года назад

    I am just greatfull!

  • @AdminTuber
    @AdminTuber 6 лет назад +1

    Best Lecturer (professor)

  • @JoinTheTechnicians
    @JoinTheTechnicians 6 лет назад +4

    *_* Pause the video and you see in each frame the B&W color wheel is in fact, truly B&W even while rotating!

  • @nodvick
    @nodvick 4 года назад

    I'm surprisingly amazed by how he made the dotted lines on the chalk board.

    • @dr_arcula
      @dr_arcula 4 года назад

      It's actually easily learnable.
      The near right angle to the surface and soft-to-firm pressure applied is the key.

  • @anuragmishra8189
    @anuragmishra8189 3 года назад

    I love Walter sir

  • @estellevanstaden5883
    @estellevanstaden5883 3 года назад

    I was once very lucky. Not only could I see the primary and secondary but a tertiary rainbow as well. On my birthday as well!

  • @dread69420
    @dread69420 4 года назад

    I should probably binge these

    • @lecturesbywalterlewin.they9259
      @lecturesbywalterlewin.they9259  4 года назад

      *Can you please tell* me why "all of a sudden" out of the blue, 75 thousand people have watched this video during the past 2 days.

  • @matematicapai-deguacomlual8514
    @matematicapai-deguacomlual8514 4 года назад

    olá professor. tudo bem. sou professor de mathematica no Brasil. muito boa suas aulas. parabens

  • @dariusmccormack7793
    @dariusmccormack7793 4 года назад +13

    the most amazing thing about this video was the part where he has some magic chalk that makes dotted lines and a funny sound. What sorcery was that??

    • @a.j.bertenshaw4539
      @a.j.bertenshaw4539 4 года назад +5

      Darius McCormack I think he’s just angling the chalk on a sharp angle away from the direction he’s dragging it so that it skips over the board

    • @crackwitz
      @crackwitz 4 года назад

      @@a.j.bertenshaw4539 that's his signature move. anyone can learn it within minutes but he has a lot of practice

    • @error.418
      @error.418 4 года назад

      He has a video on just that and how he does it. Someone even made a compilation of the times he has done it. Just search in RUclips for: Lewin chalk