i love how he hopes we find it "reasonably interesting," lol. not "incredibly" interesting or even "very" interesting. just "reasonably" interesting. :D
I swear no one teaches like Khan Academy! This is amazing, I had been trying to understand this whole concept from other videos, but for some reason, all those teachers or speakers assumed that everyone is a genius and automatically knows what they are talking about so instead of explaining, they just carry on saying a bunch of words that I have never had of.
0:38 i love that you always have such good examples to explain such phenomenons. this has actually something to do with the wave character of light. the example with the car is perfectly fitting. the light reenters the medium it just left due to its diagonal micro movements and looses speed. reentering the fast medium again, it made a curve.
Sal, you are a lifesaver! Summer classes have us learning this whole playlist in 3 days and it's going to make up around 25% of the final. I was so stressed but 3 hours of sitting down and watching this playlist actually makes it manageable. Thank you, thank you, thank you!!!
Once you had explained total Internal reflection, I whipped out my scale and even tried it in practical....and it worked....Thanks for explaining in ruch simple words and making it understandable
Thanks for this video, helped explained this better rather in class. Fully understood the concept behind critical and total internal reflection. - grade 10 student
The core has a high refractive index and it is surrounded by cladding that has a very low refractive index. There is a "cone of acceptance" (where you seem to have gotten confused; the air to 'glass' transition is not fundamental to internal reflexivity) such that for snells law, rearranged and sin90->1 crit. angle = sin^-1 (1 / huge n). the argument approaches 1/inf. and sin inverse of zero in 90 degrees. That is to say, that only if light approaches at 90 angle will it escape. :3!
thank you! It only takes me 8 mins to understand what total internal refraction is. I can't even figure out what my teacher is teaching before watching this video.
Thanks a lot for this video! It's nice to see you're constantly uploading lots of videos. Many of them are so helpful! Thank you so much for keeping this channel up and going.
So is it safe to assume that regardless of the media the ray is initially in and the final media it is in, we can use the media with the lower index of refraction in the numerator, and the higher index in the denominator? Because there's been a couple situations where I get undefined errors in my calculator. For example when a ray goes from glass to air and I use the glass in the numerator and the air in the denominator because I'm thinking n1 = glass since it was in glass first.
I see what you mean now. Did you watch the video? It explains what happens when θi becomes greater than the critical angle - you get total internal reflections. Snell's Law is still mathematically valid, given a certain set of circumstances.
once again, I don't know what would I do without your videos. so much love to you Mr. khan
Man, why cant i have teachers like this? Mine just sits there and talks like i can imagine what the .....*.... he is talking about. Thanks.
Same💔
i love how he hopes we find it "reasonably interesting," lol. not "incredibly" interesting or even "very" interesting. just "reasonably" interesting. :D
@Enrique Duran Mynenko yes
@Enrique Duran Mynenko You just asked me five days ago bro.
Alive?
@@omaralsaheb9737 bro 😭
1:26 to 2:45 is what i found most useful, thanks mate
I swear no one teaches like Khan Academy!
This is amazing, I had been trying to understand this whole concept from other videos, but for some reason, all those teachers or speakers assumed that everyone is a genius and automatically knows what they are talking about so instead of explaining, they just carry on saying a bunch of words that I have never had of.
0:38 i love that you always have such good examples to explain such phenomenons. this has actually something to do with the wave character of light. the example with the car is perfectly fitting. the light reenters the medium it just left due to its diagonal micro movements and looses speed. reentering the fast medium again, it made a curve.
Sal, you are a lifesaver! Summer classes have us learning this whole playlist in 3 days and it's going to make up around 25% of the final. I was so stressed but 3 hours of sitting down and watching this playlist actually makes it manageable. Thank you, thank you, thank you!!!
Thank you, Mr. Khan! You are the one who helps me to escape from my boring physics lesson!
thank you so much ! I litteraly study in french and english is not my first language and i’ve learned more from this video than from class😭😭
This wil help me so much for my physics test tomorrow!
Once you had explained total Internal reflection, I whipped out my scale and even tried it in practical....and it worked....Thanks for explaining in ruch simple words and making it understandable
My teacher has been explaining it for the past hour and I had no clue what she was saying. I understood right away after watching this video!
I want to keep it simple. You do great!!
Thxs a million!! Khan Academy videos have been helping me for 2years now! Sal's the best at making complex things simple!!
I need my teacher teach like you,interesting and easy-understanding
Thanks a lot. My teacher made the explanation complicated. This sums up what I need perfectly.
I appreciate the analogy of the car going from one surface to another. That's an easy one to remember.
You have carried me through my GCSE's
Thank you SO much! This has been immensely useful and makes far more sense than it did before I watched the video! Many thanks
7:24 is a glitch in real life
3:29 also glitch
7:39 another one!
Where have you been all my life *sigh*
waaay better than my teacher. I love khanacademy
This was the one part of my optics subject in school i never understood. Thanks for explaining clearly!
thank you! this video better my understanding :)
Thanks for this video, helped explained this better rather in class. Fully understood the concept behind critical and total internal reflection. - grade 10 student
Reasoning it out, your explanation from 0:28 onwards was fantastic - it just immediately clicked. Thanks for your help!
ooooooooooooooooooohhhhhhhhhhhhhhhhhhhhhhhhhhhh 1:40 shoot I GET IT now!
I found it reasonably interesting! Thanks! :3
Is this what causes all reflection? Do mirrors, for example, have such high refractive indexes that they reflect all light?
That is a very good question
The way u explain is top man 👌👌
Youve helped me in so many of my classes...... i hope you know a lot of people really appreciate this stuff. Thank you. Thank you so much.
Learned more in 6 minutes than an hour with my college professor... thanks so much.
The core has a high refractive index and it is surrounded by cladding that has a very low refractive index. There is a "cone of acceptance" (where you seem to have gotten confused; the air to 'glass' transition is not fundamental to internal reflexivity) such that for snells law, rearranged and sin90->1
crit. angle = sin^-1 (1 / huge n). the argument approaches 1/inf. and sin inverse of zero in 90 degrees.
That is to say, that only if light approaches at 90 angle will it escape. :3!
Oh my God, they never told us where the 1 comes from!! Thanks a lot! ^^ You're so awesome! :D
i love your voice and teaching skills Sal, thank you so much for taking the time to make these wonderful videos you are awesome
Thx!!! This helps so much I hope I wont fail my physics exam
These videos are the only reason that I'm able to pass my physics exam.. THANK YOU SO MUCH!
Thanks a lot..!! It was very helpful 😁..
This makes so much more sense!
thank you! It only takes me 8 mins to understand what total internal refraction is. I can't even figure out what my teacher is teaching before watching this video.
Thank you so much, you made this waaaaay easier
Respect🙌🙌
This is great! Havin a physics test tomorrow! This really helped me to understand what TIR Is!
Thaaanks , that was really helpful !
Thank u! This helps me a lot doing my school works! An amazing and engaging lesson!
bless you sal
Most beautiful channel i have ever seen.❤
Thanks you very much for the video I was facing trouble understanding total internal reflection...... Thanks a lot
This really helped a lot, I'm 14, i need to learn this in foreign German though :c this is going to be so hard xD
NZVON where did you come from?
Arolema Prarath wat
You're a life saver Mr. Khan. Now I know I won't fail my physic exam.Lots of love 💜
Man you js saved my grade tysm
Great video for understanding reflection,refraction and critical angles!
super AmaZing.....I'd rather bunk college and sit at home and learn from you......You"re amazing!!
Good
I love this guy's calculator 😍
Thank you Khan Academy... You guys are always life savers !
Thank you so much, you really helped me for my test!
Sooooooooo helpful, my exam is tomorrow and this is really going to help
Thank you very much i have a test tomorrow and i didn't know how to do it
MODY 14 me 2
+MODY 14 me 2
Thank you so much!! It all makes sense now!
Sal Khan is the GOAT🐐
right through d basics ! nailed it ! Sal u rock !
Thank you SO MUCH!!!! This helped to explain the concept and reasoning of the critical angle.
That's a great programme...
It helps me a lot!!!
helps me alot. thanks!
4:50 u can just calculate it with ur calculator and put the unknown given as an X
sir you just saved my life
Cleared things up for me, thanks!
The best explanation ❤️👏
The car example was brilliant
Thank you Mr.Khan ,your videos are very helpful .
This video helped alot!!!!
اشاهد هذا الفيديو عام 2022 ومر عليه 12 عام . اتمنى من يقرأ هذا التعليق يترجمة ويفكر في تعلم اللغة العربية لأنها رائعة
Thanks a lot man! I have an exam tomorrow, and you just helped me understand Snell's law and the whole theta critical thing a lot better!
Wow dude it’s been 8 years now u would be doing a job now right?
Dang now its been 10 years
thank you so much,you are the best Physics teacher in the entire world!! by a student from HONG KONG
what a concept of fiber optics wow amazing thanx alot
Thank you ，that was really helpful
this guys a champion
you are a GENIUS! Thanks alot
thank you so much, man. my teacher has such a strong German or Austrian accent and its hard to understand anything thanks so much
thank you so much was very halpful😉
Amazing , just amazing 👌🏻👌🏻👌🏻😬😬😬
helped me out alot. Thank you.
Thanks a lot for this video! It's nice to see you're constantly uploading lots of videos. Many of them are so helpful! Thank you so much for keeping this channel up and going.
So is it safe to assume that regardless of the media the ray is initially in and the final media it is in, we can use the media with the lower index of refraction in the numerator, and the higher index in the denominator? Because there's been a couple situations where I get undefined errors in my calculator. For example when a ray goes from glass to air and I use the glass in the numerator and the air in the denominator because I'm thinking n1 = glass since it was in glass first.
Nailed it.awesome explanation
thanks, this helped alot
Thank you SO much for this!!!!
Nice explanation 👌
This is awesome thanks! Anyone else came here from graphics/game programming?
This is awesome!
I see what you mean now. Did you watch the video? It explains what happens when θi becomes greater than the critical angle - you get total internal reflections.
Snell's Law is still mathematically valid, given a certain set of circumstances.
You explained it very well sir :D
woah
Thank you sir!!!
Man ,you are awesome
In our case -1 ≤ a ≤ 1 and b ≥ 1. And so, -1 ≤ a/b ≤ 1.
well explained
nice sal.
Superb
Too good
very good . Thank you so much.May Lord bless you