Refraction and Snell's law | Geometric optics | Physics | Khan Academy
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- เผยแพร่เมื่อ 7 ธ.ค. 2010
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Refraction and Snell's Law. Created by Sal Khan.
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The car analogy is the best thing that has ever happen to me Thx sal
Read your comment right as he started talking about it lol.
The car analogy is actually a brilliant setup to learn about Huygen's principle, which says the same thing, just using a bit of more math and geometry
The car analogy is a gift from heaven
That Car Analogy of 10 seconds... Is equal to three lectures of physics delivered by my teacher.
It's not technically correct but hey physics is merely a model at the end of the day.
lol! I took an optics class and wasn't getting why a light wave entering a glass medium would suddenly change direction either, when I suddenly had the idea of a car riding on a smooth surface suddenly hitting a rough surface with half its wheels, causing the wheels on one side to slow down suddenly; naturally, the car would veer towards the slower side until the entire car entered the rough patch. I laughed when I saw this narrator using the same metaphor I used to try to understand why a wave hitting a different medium at an angle would cause it to change direction slightly.
Same
OMG, I am thinking the same
My GOD that car analogy helped me so much
the car analogy is SO helpful. I've just been trying to memorize what way the light would bend but having an intuitive understanding is so much more helpful. thank you!!!!
Khan academy is going to be the reason I pass my exam tmrw
Did you pass?
@@aleksasmuliuolis166 He was caught snorting cocaine later that day
Did you pass? We need to know
@Aleksas Muliuolis @Rebel Pilot lol yea i did this video saved me
@@shumailakhan779 Alhamdulil'lah! Khan is our hero :)
THE CAR ANALOGY IS VERYYY HELPFUL THANK YOU VERY MUCH
The car analogy is awesome
I never got this explanation from any teacher
He's amazing!!!....
OMG! ITS LIKE THIS GUY KNOWS EVERYTHING ON THIS PLANET LOL
Dania Hasan He studies it, that's all
Dania Hasan Like a teacher would do
This sounds like the reaction of someone being taught something for the first time after being locked in an underground bunker for 20 years
Lmao
@@nalod2087 lmfao
The car example was awesome.
Sal Khan is a stinking genius.
Word from a stranger, I've worked with his family here in New Orleans. Happy to report that.
best analogy ive heard about it
You were my last ditch effort to learn this. And you did a phenomenal job! Thanks for the B+ on my Test
Good job dude
Heck yeah dude, hope you're thriving now
U must be 30 at this point
Bro must be like 28 rn
Bro, you alive?
The best part about this is that his cursor is my crosshair in CSGO
+Wacky rank?
it means that it is his mouse pointer while playing counter stroik global offense
Csgo? wtf is that
Joshed George a video game
Joshed George counter strike go online XD
Who's here in 2021? I am feeling lonely here😢
Yo
here
I gotchu bruh
Tstay hullo
great video to watch while doing blow at 3 am. I've been told
Just here to see the teaching methodology used and I am awestruck, such detailing in a relatively simple concept shows the passion of this group/guy. I am currently pursuing a masters degree and I have actually not come across many people whou would have taught this topic in such detail
Awsome work Sal
Keeo it up 👏
This made refraction so much easier to understand and explain to my son. Thank you very much!
You're a true gift to humanity, Sal!
This video was made before I even hit primary school. Now I'm learning from it 11 years after. Man this guy is heck of a teacher.
omg so genius, this car analogy make me so impressive and understand all the fxxxing thing in my textbook, thx teacher
Who's here in 2019? I'm feeling lonely here.
Im here
Thank you so much guys I feel very much better now.
chaw
Hi
Me
“That vacuum water interface example; I’m not enjoying it.” -sal
Watching this at 2x and still understands better as compared to 3 lectures! Thankss!!!!
Now that car analogy was really something
Honestly, the main thing I took away from this, as well as the actual knowledge in the video, is that the syllabus for exams has practically not changed at all in 11 years.
That car analogy really helped, thanks :)
Very nice presentation, thank you for the free class. God bless.
The example of the car was amazing.. never thought that would be similarised with the traveling of light..lol
thank you for the simple explanation! Great analogy!
Snell's law: sini/sinR=V1/V2=n2/n1. where sini is the angle of incidence, sin R angle of refraction, v for velocity and n refractive index.
I'm watching this in 2022
A vacuum is not the thing you use to clean your carpet - Sal Khan 2010
thank you so much! i totally understnad this now! got a little confused around 10 minutes but thats probably because i am only doing GCSEs at the moment. i thought the car example was so good! thank you!!!!
A verry good job #Mr.khan. You know the most interesting thing is the using of colourfull pens. Students find it more attractive :P.
Sinjini Banerjee no wonder u need to come here you spelled Very wrong
Sinjini Banerjee it's you not u
also very wrong?
Very spelling is this not verry
2017 and this helped me so much. Thanks!
i hear this guy in the many economics videos i have seen. but now physics as well.. what a man
This is a legit video man thanks for the trouble.
Thank you for this video. The car analogy was so helpful
The car example really helped a lot!
Thanks :)
Thank you so much. Your videos explain everything in perfect detail! The car analogy is so amazing! Thanks!!!!
the car's example is a the best thing !!
you're the best teacher ever !!
Thnx it was really helpful for me
That analogy with the car blew my mind.
Thankxx khan academy for this video refraction and snells law
Thanks for the car analogy. I hope to be able to better understand snell's law soon
Amazing example.. thank you
What a great explanation, thanks! I'll be using the car idea a lot :D
Thanks! Your videos helped me out a lot :)
Perfect! Very thanks!
that car analogy was awesome, thanks!
Analogy on point.
Awesome car example.. Thank you
Thanks. Now I understood it !
Thank you so much. I can't explain how much it helped me.
Well, I have understood what Snell Law is. Thanks Khan Academy. My exams are coming 2 days later, let's hope I get good grades.
Great analogy
HAHAHAHHAHAHAHAHA cramming time! Finals na bukas
Wow this really helped me with my class assignment 💯❗ he's really good
Thank you sir, Bless your days.
Excellent!!!
If the car enters into the mud, then its left part will get a force in the opposite direction, therefore creating a torque. SO the right part which is in the vacuum should also get a force resulting in it moving faster than light.
excellent analogy
This might just have saved my life.
We would like to demo Snell's Law with a laser, a glass. Please advice. We already have a simple video about the law of reflection and refraction of light .
great explanation!
i have a question
when we have to measure an angle of incidence where do i keep the base of my protractor ?
Thank you , you are the reason why I passed my physics exam
im the same, our teacher is so monotone and doesnt explain very well, this video has helped so much.
A appreciate what Khan Academy has contributed to the community
Muchísimas gracias profesor Federico Aragón, entendí todo lindo GRACIAS ENSERIO SOY FAN
The car analogy should be the gold standard for teaching this concept
Man it's been 2 years since I first saw this video and I still use that car analogy for optic problems
Fantastic !! Great explanation though. Thanks
less than 3 weeks and this has saved me
thanks great explanation
Who's here in 2020? I'm feeling lonely here.
Very Helpful.thank you
Thx for taking the trouble!
Thanks my concept are clear now
The legend sal always comin in clutch
These videos are very good. Im doing Physics HL at Ib which is the second hardest subject you could choose, and sometimes you just need to refresh your memory before a test or an exam, and these videos are simply perfect for such a purpose.
9 years later, I'm an year away from grade 11 in IB so I have to choose my HL's next year
Its a good analogy
HOW WAS THIS MADE 11 YEARS AGO!? i feel old...
You are the 🐐.
Hats off man extremely helpful.
hi this video are use full to me to understand the the conpect
watch the grammar vids XD
if u speak a different language i get it too
cus i speak hebrew mor than english
@@avocadokirby1517 Imagine if Khan Academy had a English tutorial 🤣
thank you! sir 😊
Your videos are soo helpful! Thankyou so much! :D
The car analogy is so smart
WOW , I watched this a few years ago for my first year physics , and now I'm watching this again for my 3rd year hydrogeology class .... shoulda learned the first time
U alive bro
this is great for exams
Man you the best!
Thx Now my concept is Clear
at 11:06, the simplest thing to do, is notice each factor has a "C" in it so factor it out and cancel it. And also to notice that (1/x) / (b) = 1/ (x*b), so clearly 1/(n2*sinx2) = 1/(n1*sinx1), which taking the inverse of both sides leaves the result at 12:32.
That is how I see the easiest way and fewest steps. but good video nonetheless.
I came to search for this video because you teach better than my teacher. :P Wish you taught my class physics. Everybody would ace the exams!
Thank You.
I love this guy.
Thank you soooo much
3,290 videos = lots of wisdom!
On the line normal to the interface (you draw in this line... in this video it's that dotted line that's perpendicular to the surface).
OMG! This video was 9 years ago. I feel so young right now🙄🙄
good video
continue you are the best