SUPER

yes

Leuk om weer te zien.

Professor*

Very nice!

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.

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

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

Ogeid Zepol Dr. Physics A is also nice

You NOW are my student!

Tim T. Like

YoungBlood Bear I am interested to know where you at right now?

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.

Best way to utilize OUR time and not YOUR time!!

its a circle, not a bow.

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

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.

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.

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

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

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

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?

@@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.

@@RWBHere I've seen no color :(

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

Bro.. I have biology today and it's 4:39 am

Hey man u r kind like me

:)

Thanks, Aribah, for your kind words

Right there with ya...

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

thanks Rakibul for your kind words

google "green flash"

thanks for your kind words

:)

kzfaq.info/get/bejne/qMelpc9l2JbUmok.html

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

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

Wow, thank you!

Mario Cesar Sousa Indeed. Read my book "For the Love of Physics"

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

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

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 KZfaq for: Lewin chalk

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.

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.

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.

@@Bunny_Aoife there are 3 minute tutorials on yt

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

GREAT!!

apod.nasa.gov/apod/ap240510.html

Easy, brain makes world pretty colors.

:)

The dutch accent is indeed very recognizable, but atleast he's not like Van Gaal.

You're most welcome

Come to Cambridge, MA USA and we can meet!

wow its so nice that you replied me:) now i will come as soon as possible

:)

Thank you

Glad to hear that

Glad you enjoyed it!

I dont see anything D:

@@Trashloot It doesn't work as well in video. Framerate plays a big role here. It's much better with continuous time (i.e. in real life). You buy buy such disks or make your own and spin them like a top. It's called: Benham's Disk, or: Benham's Top. Search for those terms and you will find instructions to make various versions of your own, or places to buy them for cheap. It's well worth it, it's a wonderful illusion.

Knowledge always adds, it never subtracts. Knowledge of rainbows is the "hidden" beauty, "hidden" from those who do not know.

Lectures by Walter Lewin. They will make you ♥ Physics. Watching Walter in these videos makes me sorry that I didn't get to MIT when I was a young knowledge seeker. No doubt, these science teachers will be better at their jobs after this experience. I know it helps me tremendously.

Thank you for your kind words. All science teachers were given a DVD of my lecture for many years. I gave this lecture (or something very similar) every summer for at least 5 years (probably more).

Lectures by Walter Lewin. They will make you ♥ Physics. Your very welcome. These lectures have helped me gain a more complete understanding of the nuts and bolts of physics, as well as an greater appreciation for the mathematics involved in this amazing field. Thank YOU my friend.

even I too feel the same think you seen in circle....

I'm so glad!

It is exactly what he describes. He doesn’t mention the secondary bow at 41:40.

Thank you very much! :)

:)

:)

*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.

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

:)

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.*

Glad to hear that

@@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....