The car analogy is the best thing that has ever happen to me Thx sal
@copterinx04684 жыл бұрын
Read your comment right as he started talking about it lol.
@rishavmukherjee42514 жыл бұрын
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
@roxiethecockapoo11386 ай бұрын
The car analogy is a gift from heaven
@Dr.Qureshi_4 жыл бұрын
That Car Analogy of 10 seconds... Is equal to three lectures of physics delivered by my teacher.
@Ben.N3 жыл бұрын
It's not technically correct but hey physics is merely a model at the end of the day.
@maskedmarvyl47743 жыл бұрын
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.
@sanchi74102 жыл бұрын
Same
@paulchen3552 жыл бұрын
OMG, I am thinking the same
@sarahholland59804 жыл бұрын
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!!!!
@shumailakhan7794 жыл бұрын
Khan academy is going to be the reason I pass my exam tmrw
@aleksasmuliuolis1663 жыл бұрын
Did you pass?
@sameersachan84273 жыл бұрын
@@aleksasmuliuolis166 He was caught snorting cocaine later that day
@rebelpilot70153 жыл бұрын
Did you pass? We need to know
@shumailakhan7793 жыл бұрын
@Aleksas Muliuolis @Rebel Pilot lol yea i did this video saved me
@saliknazir47683 жыл бұрын
@@shumailakhan779 Alhamdulil'lah! Khan is our hero :)
@Projectetcdubstep7 жыл бұрын
My GOD that car analogy helped me so much
@daliadarkazanli59926 жыл бұрын
THE CAR ANALOGY IS VERYYY HELPFUL THANK YOU VERY MUCH
@ayushramteke69085 жыл бұрын
The car analogy is awesome I never got this explanation from any teacher He's amazing!!!....
@Wargamer00812 жыл бұрын
You were my last ditch effort to learn this. And you did a phenomenal job! Thanks for the B+ on my Test
@Meow42.03 жыл бұрын
Good job dude
@toastedsniper9248 Жыл бұрын
Heck yeah dude, hope you're thriving now
@yahoodiagent4663 Жыл бұрын
U must be 30 at this point
@FlawHead Жыл бұрын
Bro must be like 28 rn
@paneersabzi9 ай бұрын
Bro, you alive?
@Specularrrr10 жыл бұрын
best analogy ive heard about it
@daniahasan57037 жыл бұрын
OMG! ITS LIKE THIS GUY KNOWS EVERYTHING ON THIS PLANET LOL
@zodes_7 жыл бұрын
Dania Hasan He studies it, that's all
@zodes_7 жыл бұрын
Dania Hasan Like a teacher would do
@nalod20874 жыл бұрын
This sounds like the reaction of someone being taught something for the first time after being locked in an underground bunker for 20 years
@benwalton75653 жыл бұрын
Lmao
@serendipitys-child3 жыл бұрын
@@nalod2087 lmfao
@tstayy4 жыл бұрын
Who's here in 2021? I am feeling lonely here😢
@jaleelhull9414 жыл бұрын
Yo
@huangyinghaohuang41884 жыл бұрын
here
@saroshrizvi24984 жыл бұрын
I gotchu bruh
@beforethescene78804 жыл бұрын
Tstay hullo
@DonRocco1234 жыл бұрын
great video to watch while doing blow at 3 am. I've been told
@BOBMAN19802 жыл бұрын
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.
@shivanshsingh72483 жыл бұрын
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 👏
@idontknowhowtoread76578 жыл бұрын
The best part about this is that his cursor is my crosshair in CSGO
@Adel-qo2cn8 жыл бұрын
+Wacky rank?
@danksilver16898 жыл бұрын
it means that it is his mouse pointer while playing counter stroik global offense
@gjisahappytoad94087 жыл бұрын
Csgo? wtf is that
@Adel-qo2cn7 жыл бұрын
Joshed George a video game
@DrSingh-_-7 жыл бұрын
Joshed George counter strike go online XD
@MoonCat493 жыл бұрын
This made refraction so much easier to understand and explain to my son. Thank you very much!
@jdsaaa667672 жыл бұрын
Now that car analogy was really something
@aditisingh4082 ай бұрын
Watching this at 2x and still understands better as compared to 3 lectures! Thankss!!!!
@kasperchristensen84162 жыл бұрын
You're a true gift to humanity, Sal!
@erichng16709 жыл бұрын
omg so genius, this car analogy make me so impressive and understand all the fxxxing thing in my textbook, thx teacher
@Yashraj100x5 жыл бұрын
Who's here in 2019? I'm feeling lonely here.
@mahmudjalib16315 жыл бұрын
Im here
@Yashraj100x5 жыл бұрын
Thank you so much guys I feel very much better now.
@fredsmhmd81055 жыл бұрын
chaw
@Multi15 жыл бұрын
Hi
@43_damodarbanaulikar715 жыл бұрын
Me
@sinjinibanerjee_cse_76187 жыл бұрын
A verry good job #Mr.khan. You know the most interesting thing is the using of colourfull pens. Students find it more attractive :P.
@zumbie-uf1fy7 жыл бұрын
Sinjini Banerjee no wonder u need to come here you spelled Very wrong
@samyen32107 жыл бұрын
Sinjini Banerjee it's you not u also very wrong?
@mdfayyazahmed37265 жыл бұрын
Very spelling is this not verry
@hersheyantulihao72967 ай бұрын
HAHAHAHHAHAHAHAHA cramming time! Finals na bukas
@legitabdullah8462 жыл бұрын
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.
@wilksey75069 жыл бұрын
That car analogy really helped, thanks :)
@lareterpylareny34049 жыл бұрын
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.
@victorrony21965 жыл бұрын
The example of the car was amazing.. never thought that would be similarised with the traveling of light..lol
@xukcunit8 жыл бұрын
Very nice presentation, thank you for the free class. God bless.
@mmehab47102 жыл бұрын
I'm watching this in 2022
@cd27735 жыл бұрын
“That vacuum water interface example; I’m not enjoying it.” -sal
@RandomPerson-sh9tu3 жыл бұрын
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.
@MathScienceNerds2 жыл бұрын
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.
@RushilKoshti4 жыл бұрын
A vacuum is not the thing you use to clean your carpet - Sal Khan 2010
@worcestershire029 жыл бұрын
This is a legit video man thanks for the trouble.
@GeorgieBelle112 жыл бұрын
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!!!!
@abir97554 ай бұрын
Who's here in 2024 ? 😭
@hobooo9612 жыл бұрын
the car's example is a the best thing !! you're the best teacher ever !!
@karthiyayani27558 жыл бұрын
hi this video are use full to me to understand the the conpect
@avocadokirby15175 жыл бұрын
watch the grammar vids XD
@avocadokirby15175 жыл бұрын
if u speak a different language i get it too cus i speak hebrew mor than english
@metastag4 жыл бұрын
@@avocadokirby1517 Imagine if Khan Academy had a English tutorial 🤣
@bakhtawara39025 жыл бұрын
Analogy on point.
@jerrigaa6 жыл бұрын
thank you for the simple explanation! Great analogy!
@eshanths8652Ай бұрын
Can we use Snell’s law equation like the sine rule equation, like flipping the fraction to find the angle or side?
@Borzacchinni6 жыл бұрын
i hear this guy in the many economics videos i have seen. but now physics as well.. what a man
@trentfeda65075 жыл бұрын
The car analogy should be the gold standard for teaching this concept
@wisehead18305 жыл бұрын
Thank you for this video. The car analogy was so helpful
@anshul985611 жыл бұрын
5:51 Wrong Direction! Its going to turn towards the left I think as- you said that the tyres should be moving AWAY from the other medium.
@mdeluca012 жыл бұрын
That analogy with the car blew my mind.
@liu20113284 жыл бұрын
This might just have saved my life.
@sha-yr7bw3 жыл бұрын
that car analogy was awesome, thanks!
@beautifulquranrecitationle6319 жыл бұрын
What about refractive index of multiple media like for example Air Water Glass Find refractive index of glass with respect to water
@sekisenpai78784 жыл бұрын
Wait but im studying sin(i)/sin(r) For snells law
@maryamimran15294 жыл бұрын
Me too..😕. I think it's another version of snells law. We can get to the formula discussed in the video by some kind of derivations 🤔👇 sin(i)/sin(r) is same as sin _Oi_ /sin _Or_ which equals (=) n2 / n1(the change of refractive index) ... So after cross multiplication we get. n1 sin _Oi_ = n2 sin _Or_ If it's wrong I hope someone else will help us 🙁 (sorry for bad English)
@fan5074 жыл бұрын
Who's here in 2020? I'm feeling lonely here.
@yashbadjatya44949 жыл бұрын
Thankxx khan academy for this video refraction and snells law
@sejaltreebhowon60098 жыл бұрын
Thnx it was really helpful for me
@ToddBeamQ11 жыл бұрын
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 .
@gavintoohey66044 жыл бұрын
Thanks for the car analogy. I hope to be able to better understand snell's law soon
@nileshkumar98698 жыл бұрын
thank you! sir 😊
@NooreddinPirzadeh10 жыл бұрын
Very Helpful.thank you
@juanestebanamezquita42194 жыл бұрын
Muchísimas gracias profesor Federico Aragón, entendí todo lindo GRACIAS ENSERIO SOY FAN
@freydawg5613 жыл бұрын
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.
@pabsswede874010 жыл бұрын
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
@INV-HASSAAN8 ай бұрын
U alive bro
@saadahmad21055 жыл бұрын
Sul since the light is entering from denser to rarer medium isn't it supposed to turn away from the normal? 5:54
@sarujanrupan48314 жыл бұрын
Ye it did that
@garimasingh780910 жыл бұрын
The car example really helped a lot! Thanks :)
@michelletian561910 жыл бұрын
Thanks! Your videos helped me out a lot :)
@harshpatil20469 жыл бұрын
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.
@michaelpereira57237 жыл бұрын
2017 and this helped me so much. Thanks!
@quincithomas92256 жыл бұрын
Wow this really helped me with my class assignment 💯❗ he's really good
@luisguzmanbedolla33563 жыл бұрын
HOW WAS THIS MADE 11 YEARS AGO!? i feel old...
@doomofmalantai12 жыл бұрын
im the same, our teacher is so monotone and doesnt explain very well, this video has helped so much.
@Life0jazz13 жыл бұрын
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.
@TheKokiriMusician3 жыл бұрын
9 years later, I'm an year away from grade 11 in IB so I have to choose my HL's next year
@pavsjoga22713 жыл бұрын
OMG! This video was 9 years ago. I feel so young right now🙄🙄
@balreddy79296 жыл бұрын
Do reflection and refraction occur at the same time?
@pantopia35184 жыл бұрын
Ballreddy Reddy yes Some of the light will reflect and some will enter and refract, the total intensity of the combined reflected and refracted Ray will sum to the intensity of the incident ray
@christinamorin19143 жыл бұрын
Would it still be correct to say that refraction in a more dense medium causes the image to appear to be pulled down? When I hold a horizontal pencil behind a plastic cup of water, the image of the pencil in the water is below the actual image.
@NadinePigida7 жыл бұрын
Thank you so much. Your videos explain everything in perfect detail! The car analogy is so amazing! Thanks!!!!
@mariamansour84457 жыл бұрын
The car analogy is so smart
@smashadams981112 жыл бұрын
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).
@animatebig11 жыл бұрын
Woah great explanation....... I was able understand it very easily . I think Science becomes more easy and enjoyable when we understand and learn it. Car example was the best :)... Thanks
@harshithvarma19102 жыл бұрын
man are you still alive
@harshithvarma19102 жыл бұрын
you were watching this video nine years ago while i was in my first grade im in 10th now and i wanna know what you're upto nowadays after 9 years
@jithunniks2 жыл бұрын
Haha, I'm 25 now, I work as a software developer now
@fahadrahman54416 жыл бұрын
Man it's been 2 years since I first saw this video and I still use that car analogy for optic problems
@dhruvsingh14636 жыл бұрын
Amazing example.. thank you
@manjuprasannakumar22225 жыл бұрын
Awesome car example.. Thank you
@sachikaboyagoda12753 жыл бұрын
You are the 🐐. Hats off man extremely helpful.
@tyftfyuhgvfyci8r.aravalor7 ай бұрын
excellent analogy
@sprZLCHO8 ай бұрын
Great video! Btw guys you dont need to imagine the wave having wheels, the the wave has wave fronts which if you draw them you will understand why it works!
@cyberprodigy13 жыл бұрын
Optics is cool topic in physics, because it is visual and can be observed all around you walking down the street.
@allelements99676 жыл бұрын
The legend sal always comin in clutch
@lopamudrakar56806 жыл бұрын
Excellent!!!
@Kyun94329 жыл бұрын
What a great explanation, thanks! I'll be using the car idea a lot :D
@anuruparoychowdhury65707 жыл бұрын
Thank you so much. I can't explain how much it helped me.
@Ethernet311 жыл бұрын
The way my book explains it is quite confusing, they don't use n1sin(O1) = n2sin(O2), but n(air -> stuff) = sin(angle in)/sin(angle of refraction). Which gets confusing when you have to go from stuff to other stuff( you have to make sure you have the right n, as everything is given in the form air -> stuff).
@sheemanisthar34364 жыл бұрын
Fantastic !! Great explanation though. Thanks
@surry99 Жыл бұрын
This is exactly why you DO NOT want something with a math and economics background (even from MIT) trying to explain basic physics. He really should consult with a mechanical engineer before discussing analogies involving cars. He clearly does not understand terms like: 1) rolling without slipping 2) traction control 3) tire contact patch etc.
@naveensundar4765 Жыл бұрын
It's just an analogy bro it doesn't matter
@surry99 Жыл бұрын
@@naveensundar4765 In your opinion is does not matter
@surajrao74218 жыл бұрын
hey can you let me know of any software to record the screen and write?
@jayj81426 жыл бұрын
Suraj Rao obs is a great recording software.
@bhavanabawaskar56374 жыл бұрын
Thx Now my concept is Clear
@chasemarangu3 жыл бұрын
The car's wheel analogy is weird but helpful
@xoguy21954 жыл бұрын
plz, when you say next video or previous video, can you put the link to those videos in the video
@EclipseCries12 жыл бұрын
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!
@abdulazizghamdi9611 жыл бұрын
Thanks. Now I understood it !
@chiorrimd6 жыл бұрын
Perfect! Very thanks!
@tatemurtaugh279510 ай бұрын
Rio Salado Community College is using these as teaching material. I should hope some of my tuition is being donated to you, since you're doing the teaching for them.
@manahiljaved17834 жыл бұрын
Thanks my concept are clear now
@aliiskandarli Жыл бұрын
Thank you , you are the reason why I passed my physics exam