Snell's law example 1 | Geometric optics | Physics | Khan Academy
ฝัง
- เผยแพร่เมื่อ 7 ธ.ค. 2010
- Courses on Khan Academy are always 100% free. Start practicing-and saving your progress-now: www.khanacademy.org/science/p...
Snell's Law Example 1. Created by Sal Khan.
Watch the next lesson: www.khanacademy.org/science/p...
Missed the previous lesson? www.khanacademy.org/science/p...
Physics on Khan Academy: Physics is the study of the basic principles that govern the physical world around us. We'll start by looking at motion itself. Then, we'll learn about forces, momentum, energy, and other concepts in lots of different physical situations. To get the most out of physics, you'll need a solid understanding of algebra and a basic understanding of trigonometry.
About Khan Academy: Khan Academy offers practice exercises, instructional videos, and a personalized learning dashboard that empower learners to study at their own pace in and outside of the classroom. We tackle math, science, computer programming, history, art history, economics, and more. Our math missions guide learners from kindergarten to calculus using state-of-the-art, adaptive technology that identifies strengths and learning gaps. We've also partnered with institutions like NASA, The Museum of Modern Art, The California Academy of Sciences, and MIT to offer specialized content.
For free. For everyone. Forever. #YouCanLearnAnything
Subscribe to Khan Academy’s Physics channel: / channel
Subscribe to Khan Academy: th-cam.com/users/subscription_...
omg thank you dude u taught me the last 4 months of science in like a day of videos. teachers should use this for class
Your terrific analogy of car going from road to mud (or sand) really hit the spot for me.. Thanks!
I am convinced that all your blessed educational efforts have proven VERY fruitful the world over :)
thanks a million!! it all makes sense now! first time my teacher mentioned those it was as if he was speaking latin, now its so simple!
thank you so much!! I was ready to cry when I tried to understand snell's law and couldn't grasp it. now I no I wont fail that portion of my test tomorrow ;) God bless!!
I hope you're not taking an English exam as well
don't listen to the guy who is above my comment.
I am a biology teacher, but I am asked to teach a general science course including this topic. Thanks so much. :) Teacher helping teachers.
thanks so much Sal. if I get good marks in my boards in phy. I'll give full credit to you.
+Lavanya Jha Me too lol
So.. how was it?
I will wait here 'til they reply
@@mattadrianlai4825 lol 10th grade was terrible, 12th grade i ended up topping my country cus i ditched physics and math lololol
@@lavanya-wo5gj Wow That's really nice, Keep up the Good Work!
Sal, U made me understand the concept which i was trying to learn & understand since last 2 weeks xD TY MAN
Thank you SO much for making this video!! It was insanely helpful!
You just saved my physics final. I thank you kind sir.
I paused the video at 2:01, got my TI-85 out and did the calculation. It was pretty funny (well, to me anyway) that the next step in the video was a TI-85 appearing on the screen working it out :)
Thank you soooooo much for this useful video, my hope of passing this physics exam rise again!!!
you saved my life dude , thanks !
I PASSED! ILY MAN
Dude amazing vids... i have a test in two days and im set!
Thank you so much I understand this so much!!!
Thanks man my physics exam is tomorrow and am sure am gonna pass
Great as always!!!
thx alot
you are a good man
For the second example I looked up what the material could be, and with an index of 1.29 the material was Fluorine refrigerant R-12. Khan Academy
you are the best teacher in the wold ...
Thank you! But I have one question. In the second example another formula I am familiar with to find refractive index is sin i/sin r = n . Isn't the angle of incidence 30° and the angle of refraction is 40°? Therefore the refractive index of the unknown medium = sin 30°/sin 40° = 0.78?
yep, it definitely does if its going into your head!
The refractive index for *Dichlorodifluoromethanerefrigerant R-12* is 1.29
Texas Instruments website lets you download some of their calculators. The one Kahn uses looks like the TI-83. (Very handy for graphing on your PC.)
THANK YOU
this is literally going to be the reason i pass my exam
Thank you for this video! =D
Thank you so much
Where can I download that calculator? That is awesome!
So the general formula for it is nsin angle of inidence = sin beta 2
Thank you
excellent video
Ty so much
I understand where you are coming from. But you have to understand that when we are talking about the refractive index of a material we are saying that when light travels from air(or preferably a vacuum) into that material. So in essence, you are kinda using the 40° as the incident ray.
YOU ARE AMAZING
U just saved me from failing my science!
XD
Thank you guys I love ya 💜💜💜
THANK YOUUUUUU LIFE SAVER
So good
is there a way to solve for the angle Theta without using the calculator
i can't even use his calculator
Anyone watching in CoronaVirus Quarantine?
No, only me? OK
Here!
Trying to get ahead of my class, lol
Nop
lovedddddddddd ur calculator..loll =P
thnk u so much Mr.Khan
do people only from texas us Tis or do others states use them too! im interested to know.
Ryan Kubosh they're used everywhere, teachers in my school use them. I'm from Canada
I wish you were my teacher :( anyway tks!!
i wonder if watching videos like this counts as studying?
Can anyone shed light on what the critical angle is? I am trying to solve a problem in which it gives a critical angle and asks me to find a refractive angle. Thank you.
critical angle is the angle of incidence in the denser medium corresponding to which the angle of refraction in the rarer medium is 90 degree.
Hey, I'm doing physics right now and I'm not that good at maths.. I was just wondering if you have a video that teaches how to solve for theta in that equation because I can get the equation but I don't know how to solve it. (sorry if it sounds stupid) :\
Would anyone know what the topic I should practise in maths to get better at this would be?
Thanks heaps btw, you're video's are great!
Thanks
Shame...no one helped you
trigonometry
Where'd you get that calculator? O_O
So finding the refractive index is basically n= sin r/sin i? I thought finding the refractive index is n= sin i/sin r?
ikr
I think it was a small mistake...but i guess since minority of us saw the mistake we special😂
Ye you right you are special
@@nalod2087 huh?
thanks a lot :) hahaha
I'm still not getting degrees
your a beauty
@pysgodfach ..snell's law =]
the air should be 1.0003 not 1.00029
God bless your soul for rounding it.
Pratham Shah was that a thank you? haha
YOUR CALCULATION IN THE SECOND EXAMPLE IS INCORRECT! the absolute refractive index is supposed to be 0.78 where sin 30 is divided by sin 40. you made a mistake and did it the other way around. the refractive index is equal to the sine of incident angle divided by the sine of refractive angle.
youre dumb
i was looking for a comment like this thought i was the only one
ca13 how can the refractive index be lower then 1? I think you got it mixed up. Sorry bud but ur wrong
INCORRECT BANISH HIM!
i want your calculator!!!!!
Thanks for the reply even if my comment was already a year old. :p
jonrty007 ima reply 7 years later :p
Hi
You need a calculator to work it out.
You are god.
lol super slow :)) 9:57