Refraction in water | Geometric optics | Physics | Khan Academy

Refraction in Water. Created by Sal Khan.

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[platcrab]

that is an actually impressive face you drew

[ownthispwn]

2:37 that was scary how well he drew it in that small amount of time lol

[mustang]

2:31 - the end of this video:
THIS IS WHERE IT STARTS TO MAKE SENSE. This is the most helpful part of the video, at least to me. If anyone agrees, just let me know if I helped. :)

[gtasanandreas]

Who are we? Students!
Who is our saviour? Sal!

[RyanLynch]

it looks like it looks like it looks like

[alizehfaisal]

KHAN ACADEMY IS SAVIOR! THIS IS THE EXACT CONCEPT THAT I DIDNT UNDERSTAND! This channel never lets me down :) thanks this was very useful!

[Voltar]

you forgot the cup glass which also alter the image. experiment on a square glass, convex and concave glass. also the thick and thin glass that can magnify the image

[tadm]

i mean wouldn't it be better in books that they would teach us whats the velocity of light in every medium instead of learning its refraction indexes? :o

just a curiousity

[monsterzz]

You are really good. I really needed help for my Science Project. Thank you so much! I will continue on watching your video's. =)

[KYibbs]

I LOVE THIISSSS!! THANK YOU SO MUCH THESE VIDS ARE SO HELPFULL

[WolfyzPW]

It all makes sense, I think I might just watch all of these videos... if only I can stop time.

[AhishDeshpande]

Very good vid, u earned 1 subscriber!!

[Voltar]

you forgot the cup glass which also alter the image. experiment on a square glass, convex and concave glass.

[its_rapper_boy]

Thankyou sir I enjoyed it❤️
Also drawing 😀

[rne]

You are awesome...this will go great with my computer graphics understanding. Thank you

[Illogical.]

I can't think of it as a car or marching band.
The way I understand it, a photon is 1 thing that sometimes behaves like a wave, and sometimes behaves like a particle. And photons don't stick to other photons, so a group of them can't bend by speeding up one side.

And photons are so small that thinking of the 3d edge between the water and air as a flat surface doesn't make sense. That doesn't feel right, but I can't think of a reason for that being incorrect. I think I need the explanation for why that is wrong before I can really understand this properly.

How can one 'side' exit the water before the other 'side', when it is essentially an infinitely small point, and not multiple particles?

You must be leaving out a(/some) key detail(s). Or maybe I am missing some basic knowledge about how light works, like for example the stuff I mentioned in the second paragraph.

edit: Also, what you're saying can't be right? Since you'd see different parts of the straw at different places in the water, those different places would have different angles, meaning the staw would appear curved.
But to me, the straw under water appears to be straight?

[mustang]

Khan Academy PLEASE DO SOCIAL STUDIES LESSONS! PLEASE??

[indianajesusfreak]

That's why I don't take baths.

[itsmireiasworld]

But why does the lighrt bend? Is it because the change in the medium? The slower-faster thing?

[coolguytan]

i think its coming from an external light source, such as a lightbulb