Diffraction grating | Light waves | Physics | Khan Academy

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What happens when there's way more then two holes? Created by David SantoPietro.
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Опубликовано:

6 июл 2014

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Комментарии : 316

@SAKA701 7 лет назад

Grate video, must say.

@chrisbuckle6930 7 лет назад

Aly Azeemi great*

@SAKA701 7 лет назад

Chris Buckle Ik dude, it was a pun :p diffraction grate-ing. YES IM THE LORD OF ALL BAD PUNS.

@divyasingh9291 7 лет назад

Aly Azeemi ikr😂😂

@SAKA701 7 лет назад

TOP COMMENT WOWOWOOW, FeelsGoodMan :D

@the_golden_one4733 6 лет назад

Dont grate on my nerves

@bboy14 8 лет назад

Khan academy needs to keep you on board, your explanations and commentary style is a treat!

@Cooltaha 7 лет назад

such a clear and concise voice

@fluffzxx9615 3 года назад

I don’t get why in the normal double slit it would be smudgy in the first place, why?

@albertvandrejer5003 3 года назад

@@fluffzxx9615 because for a large numer of slits, the condition for constructive interference of all the superimposed waves is only given at very specific positions. For a double slit what you see is just the interference pattern of two waves, which will have areas of constructive interference, destructive interference and everything in between.

@williamstephenjones3863 Год назад

Agreed

@ponypony4695 9 лет назад

If only my teacher at university could explain this in the way you did... thanks, now it looks much more easier to understand ;)

@LASTCHANCE-mi8zy 5 месяцев назад

says who

@kushalchakrabarti240 5 лет назад

4:03 .. how about a third hole? This is where it gets interesting... LMAO

@expectopetronum3851 5 лет назад

😂😂😂😂😂

@abdallababikir4473 4 года назад

Brother,😂

@AbdulHamid-uw2oe 3 года назад

Mouth..vagina...&...... The thid....

@mr.j_krr_80 6 лет назад

10:55 "in between you'll get *darkness* " me: I know... *turns off light, sits at the corner and falls into depression*

@yashgaikwad7516 6 лет назад

Mr. J_Krr_ :(

@MJ-hq1ie 5 лет назад

A whole mood

@splinter1817 4 года назад

sed lyf

@Postermaestro 8 лет назад

This was very well explained. You guys at Khan are so good at making it easy to understand, which makes the learning process so much more fun and time-efficient!

@sarahholland5980 4 года назад

you just explained a full lecture in 15 minutes, and beautifully and simply. bless you.

@ufo717212 5 лет назад

I just tried to reorganize your points in my own words as the following. At a magical spot, each light travel one wavelength further(or less) than its adjacent light. Therefore all lights results in constructive interference at this spot which is bright. At a non-magical spot, each light has a slight phase difference with its adjacent light. Since there could be hundreds of different lights from hundreds of holes, each light can always be paired with another light with a phase difference of about half wavelength. Thus each pair results in destructive interference. Overall they result in darkness at the spot.

@kissmyussr1993 4 года назад

Who are you so wise in the ways of science?

@vandnashukla3598 3 года назад

This is exactly how I tried understanding it.i took approximately half of the total number of holes and then each point in between the initial and final hole would pair up destructively with another.

@Ahmed-vs1ui 3 года назад

How does that magical spot even exist mathematically

@cortwill4085 3 месяца назад

OH... ME... GOSH!! IS THIS... ARE YOU... KHAN ACADEMY KIDS?!?!?!?!?!?!?!?!? I LOVE Khan Academy Kids so much! l couldn't even help myself but to get a game of you guys on my iPad! I like all the characters: Peck, Ollo, Kodi, Raya, and Sandy! But I think... Sandy's my favorite! Khan Academy Kids is all l play! Like, I literally don't want to play anything else on my iPad! CONGRATS!🎉 You get 5 stars!⭐⭐⭐⭐⭐ I wanted to give you 5 stars in the game, but it required a PIN that only Mum and Dad knew. And they won't give me permission to give you 5 stars. Here you go!:⭐⭐⭐⭐⭐

@sotirissarros3522 9 лет назад

many thanks man. it's clear that you really want to explain the subject and you do it perfectly!! well done!!

@zeenathunnisa3571 5 лет назад

Gosh!! Such an awesome and clear explanation. Jazakallah Khair.

@annaszinyei 9 лет назад

You did such a great job explaining! So clear and easy!

@mariamnaeem6963 Год назад

Wow!! Thank you for posting such a wonderful explanation! I was so confused that how wavelength is determined and you have cleared this concept briliantly!

@Integrelle 6 лет назад

2:12 "Why? Well, lets talk about why." LOL, reminded me of the GMM quote, "Lets talk about that".

@LanNguyen-iu3oe 7 лет назад

Thank you so much! your videos on diffraction and the slit experiment really helped me fully conceptually understand the process.

@Lyoko-wy3si 9 лет назад

I barely understood the idea of diffraction grating until I watched this! Thanks for the help

@abuhshadid5938 5 лет назад

You explained it just perfect.... You make some great videos on physics.... You really are a great tutor... It turns out that my teacher doesn't have any time to explain everything like you do... So I'm very much grateful to you, David SantoPietro...

@alivira1558 7 лет назад

Never understood what the concept was before but this was like magic.. well done and thank you so very much.

@wildmindentertainment2685 8 лет назад

Subscribed, very good explanation. We see stuff so superficially at high school that sometimes I must understand more graphically thr whole phenomenon and not just admit results as they would want us to do it.

@4rthur4rmstrong 8 месяцев назад

All David’s videos on physics has been absolutely amazing!

4 года назад

"And in between these bright spots you will get darkness...which is grate."

@fluffzxx9615 3 года назад

I don’t get why in the normal double slit it would be smudgy in the first place, why?

@epickirby101 2 года назад

Fluffz Xx cause the waves won’t completely cancel out in between, partial destructive or constructive interference

@kitanomarumilitoni9293 5 лет назад

I understood that very well. Great job sir thank u very much!

@lewiduressa 3 года назад

This explanation is very clear. I read my physics book on this topic, and added with this video, it makes sense! Thanks

@MrRak18 9 лет назад

It helped me understand x- ray diffraction.. thank you.

@faizanrizwan786 7 лет назад

so comprehensive! thank you!

@markren626 Год назад

This super amazing explanation made me think of the animation of 3b1b’s fourier transformation animation, the little dots moving on the sine wave and add up their values is just like the process of wrapping a metal wire around a circle and find its center of mass!

@animeBHARATIYA Год назад

The explanation is very clear, thank you

@tom_something 5 лет назад

This is super clear, thank you. One thing I was wondering as I looked at this. Shorter wavelengths should, then, encounter these positive interference peaks at smaller angles. And I was trying to reconcile that because I know "blue light diffracts more than red light". But I looked it up, and in a diffraction grating, blue dots would be _closer_ together. I had assumed a diffraction grating would work the same as a prism or the sky. But nope. So the observation of dot spacing with regard to wavelength through a diffraction grating is totally consistent with the model you've outlined, which is really satisfying.

@simonhwang5624 6 лет назад

Right at 3:00, you say "draw a right angle", but if it's a right angle there's no way the two lines (minus the "extra part") are equal, because geometry: hypotenuse of right triangle must be longer than sides.

@adityamathur5972 4 года назад

Same bro, even I didn't get that

@nononnomonohjghdgdshrsrhsjgd Год назад

@@adityamathur5972 i was scrolling through the comments to find that question and some explanation

@smtusharibnesalam8688 2 года назад

Its Great. Mind blowing. Top class video. Thank you very much for teaching this

@MariaShchurova Год назад

That;s incredible. Thank you for your work

@trailertrashtactics 5 лет назад

This guy is like a young sassy Sal Haha. Love it thank you for the videos.

@aashwinsharma1859 4 года назад

Just understood the concept in 15 min which I couldn't understand in days. Great explanation

@allaryyan6608 8 лет назад

wow..that is amazing, thanks alot!

@bondlets2342 8 лет назад

Thank you so much! You guys are awesome!

@chrisjieyanglee5360 7 лет назад

thanks bro you've helped me alot!!

@RedBar3D 9 лет назад

Actually drawing them parallell seems to help understanding a whole lot

@jinks6887 7 лет назад

really well explained thanks a lot ..love from india

@navarundas1878 6 лет назад

great explanation..much appreciated!

@RahulGupta-pf4yt 5 лет назад

Your style of teaching is remarkable.

@malezacaminante9577 9 лет назад

This videos are just amazing!

@4darekord 8 лет назад

crystal clear explanation man

@1Rise 3 года назад

you explained the destructive concept perfectly and easy to understand.

@TimeGrowing 6 лет назад

Hey man you just killed it's been one month on school teaching me,but I didn't understand. And you, just in 14m you make it easier than drinking water. Thank you so much.

@intesar6341 9 лет назад

Thank you ... now its clear for me

@luigiprz5319 3 года назад

Hi, to keep angles, so green lines, the same, the purple lines should be parallel. We cannot approximate angles because the difference distance is much bigger than wave length. Correct me if I'm not right. It looks the same when draw is not precise but geometrically not. What if first hole will be perpendicular to bright spot and the x hole will be at the border of light point :) but you got good intentions it's the plus

@hoangphamcong9230 7 лет назад

realy clear! Love it

@gracepancalstatela4422 8 лет назад

best explanation!!! Thanks a lot .

@hokwanchan4142 4 года назад

the video gives me a clear idea of diffraction.thanks

@inku.1593 6 лет назад

You are amazing 👑👑. Even I don't speak English every time I see you explaining something I feel happy inside of me . Becouse you make studing physics fun .

@workingemail1016 3 года назад

Very well explained. Thank you.

@adreekazafor2410 3 года назад

i think i don't even need to go through the topic anymore thanks

@5vart5ol 6 лет назад

Dude! You really have to become a teacher! Cause the way you explain! You make it so it feels sooo interesting! Which it is! TEACH MORE!

@kushalchakrabarti240 5 лет назад

This guy is great!

@angikmukherjee1226 7 лет назад

You nailed it man!

@astroknight5 2 года назад

Beautifully illustrated!

@patrickneal9288 2 года назад

such a good explanation thank you !

@banterbus4297 9 лет назад

thanks so much you helped me understand it so much better

@tylerlitch3992 8 лет назад

What screen recording software do you use? I would like to know a good one that allows me to pause recording.

@vardanhovakimyan7633 5 лет назад

good job, buddy! thanks

@jasonhng8135 8 лет назад

nice video about diffraction grating!

@udays6170 2 года назад

Beautiful explanation!

@aritramondal4010 5 лет назад

Great video made all clear.

@SohamChakraborty42069 3 года назад

Beautiful explanation. One part I don't understand though. The angle theta is the angle between the perpendicular line joining the middle of the distance between the pair of slits and the screen and another line that joins the middle point and the point of interest on the screen. In diffraction grating, we are choosing different pairs of slits each time, so the middle point changes whereas the point on the screen remains fixed. How is the angle the same, then?

@Adrian24134 4 года назад

great explanations!

@supersonic174 9 лет назад

One thing that could be helpful to point out is that in areas of deconstructive, when ever the wave arrives at the screen there will always be a collection of smaller waves or troughs.. even as time passes, as time moves forward. As the trough hits the screen there will be waves hitting the same point causing deconstructive interference and vice versa.

@sayan_debnath 3 года назад

Great explanation.. Thank you

@physestryshorts5214 15 дней назад

omg ..... no words for this lecture

@MohdSameer-rx9gj 3 года назад

Very very nicely explained.....!!

@poiuwnwang7109 3 года назад

That makes sense to me, Khan.

@fahamidaani9597 6 лет назад

wow you explain it so easily

@GoogleUser-ee8ro 8 месяцев назад

so clearly explained

@ChanakyaVivekananda Год назад

Mannnnnnnn This is such a good explanation!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!

@craetydonutkey1348 3 года назад

For the deviated spot, i think if you just draw out all the possible waves on the same graph you could tell they are interfered destructively by their adjacent waves at each intersection. In other words, I think any space between the integer wavelength lambda will always be dark, resulting in discrete bright spots on the screen.

@wooluke7144 Год назад

Wow. Very Well Done. All Capitals Letters.

@yeonjin8 3 года назад

First time watching an English explaination but still it's so good❤️👍

@harshilkaswala1886 7 лет назад

awesome Vedic loved it

@lazyz8969 7 месяцев назад

Great Explanation

@haristufail2121 8 лет назад

Beautifully explained Sir.You should get a Noble prize.

@FDGod99 8 лет назад

-_-"

@FDGod99 8 лет назад

+Onkar Apte -_-"

@gracepancalstatela4422 8 лет назад

I agree👍.

@LogicalCod 5 лет назад

Nobel

@harrisabdullah2278 5 лет назад

If there was a nobel prize for teaching

@user-de2pm7vr7y 3 месяца назад

Thank you for making this video. 🙏🙏🙏🙏🙏🙏🙏🙏🙏🙏🙏🙏🙏🙏🙏🙏🙏🙏🙏🙏🙏🙏🙏🙏🙏🙏🙏🙏🙏🙏🙏🙏🙏🙏🙏🙏🙏🙏🙏🙏🙏🙏

@BlueRangeTV 3 года назад

Thanks, the Bulgarian student books don't explain this well at all! Finally understood it

@tajungnuksungpongen4339 7 лет назад

thanks your AWESOME....

@miyu6720 Год назад

khan academy saving my grades I FREAKING LOVE YOUUUU

@vinaykumardaivajna2470 6 лет назад

Wow great thank you u guys are ....great...thank you so much.....

@Cherrilady83 5 месяцев назад

God Blessed this man.. Tysm❤

@bithipaul6810 5 лет назад

Great video..sir..outstanding...

@DaDream6 8 лет назад

reflective grating vid would be dope

@ernstuzhansky Год назад

Great video!

@SkillSasaBoy123 7 лет назад

Thanks so much for this

@sivasamymurugasamy3998 6 лет назад

wow...wonderful..

@mrlisterresistor9695 5 лет назад

I got it the first time only thanks to your explanation

@mastersanjay7642 3 года назад

Amazing explanation and content hat tip

@rishabhattri6055 6 лет назад

Very well explained

@antoniadukmenic627 4 года назад

Thank you sooooo much! 💞

@mangatons 8 лет назад

great vid!

@user-hz4lu5po3r 3 месяца назад

2024 and this video still working great 😃👍 thx for the explanation you're doing amazing!

@grizzers21 5 лет назад

easier than reading a textbook. Thanks!

@rachanamuralinarayanan7391 6 лет назад

Brilliant!

@starcrosswongyl 7 лет назад

hi, nice work there, i am still not too clear. Could it be of superimposition of waves with a phase angle between them thus causing beats (resultant wave between the many waves, correct me if i am wrong).

@eduarddez4416 2 года назад

At the last part when you showed us that if you slightly deviate from the maximum point you said that there will be destructive interference and it will cancel each other out , but won't there also be constructive interference for example after the 10'th slit ?