Diffraction grating | Light waves | Physics

Diffraction grating | Light waves | Physics | Khan Academy

Рет қаралды 905,678

10 жыл бұрын

What happens when there's way more then two holes? Created by David SantoPietro.
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Пікірлер: 316

@bboy14 8 жыл бұрын

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

@Cooltaha 7 жыл бұрын

such a clear and concise voice

@fluffzxx9615 3 жыл бұрын

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

@albertvandrejer5003 3 жыл бұрын

@@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 Жыл бұрын

Agreed

@SAKA701 7 жыл бұрын

Grate video, must say.

@chrisbuckle6930 7 жыл бұрын

Aly Azeemi great*

@SAKA701 7 жыл бұрын

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

@divyasingh9291 7 жыл бұрын

Aly Azeemi ikr😂😂

@SAKA701 7 жыл бұрын

TOP COMMENT WOWOWOOW, FeelsGoodMan :D

@the_golden_one4733 6 жыл бұрын

Dont grate on my nerves

@ponypony4695 9 жыл бұрын

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 ай бұрын

says who

@cortwill4085 2 ай бұрын

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@kushalchakrabarti240 5 жыл бұрын

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

@expectopetronum3851 5 жыл бұрын

😂😂😂😂😂

@abdallababikir4473 4 жыл бұрын

Brother,😂

@AbdulHamid-uw2oe 3 жыл бұрын

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

@ufo717212 5 жыл бұрын

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 жыл бұрын

Who are you so wise in the ways of science?

@vandnashukla3598 3 жыл бұрын

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 жыл бұрын

How does that magical spot even exist mathematically

@Integrelle 6 жыл бұрын

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

@sarahholland5980 4 жыл бұрын

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

@mr.j_krr_80 6 жыл бұрын

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

@yashgaikwad7516 6 жыл бұрын

Mr. J_Krr_ :(

@MJ-hq1ie 5 жыл бұрын

A whole mood

@splinter1817 4 жыл бұрын

sed lyf

@zeenathunnisa3571 5 жыл бұрын

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

4 жыл бұрын

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

@fluffzxx9615 3 жыл бұрын

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

@epickirby101 2 жыл бұрын

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

@Postermaestro 8 жыл бұрын

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!

@annaszinyei 8 жыл бұрын

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

@sotirissarros3522 9 жыл бұрын

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

@Lyoko-wy3si 9 жыл бұрын

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

@mariamnaeem6963 Жыл бұрын

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!

@alivira1558 7 жыл бұрын

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

@LanNguyen-iu3oe 7 жыл бұрын

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

@abuhshadid5938 5 жыл бұрын

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...

@kitanomarumilitoni9293 5 жыл бұрын

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

@MrRak18 8 жыл бұрын

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

@4rthur4rmstrong 8 ай бұрын

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

@lewiduressa 3 жыл бұрын

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

@faizanrizwan786 7 жыл бұрын

so comprehensive! thank you!

@wildmindentertainment2685 8 жыл бұрын

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.

@animeBHARATIYA Жыл бұрын

The explanation is very clear, thank you

@MariaShchurova Жыл бұрын

That;s incredible. Thank you for your work

@allaryyan6608 8 жыл бұрын

wow..that is amazing, thanks alot!

@trailertrashtactics 5 жыл бұрын

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

@malezacaminante9577 9 жыл бұрын

This videos are just amazing!

@smtusharibnesalam8688 2 жыл бұрын

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

@chrisjieyanglee5360 7 жыл бұрын

thanks bro you've helped me alot!!

@TimeGrowing 6 жыл бұрын

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.

@simonhwang5624 6 жыл бұрын

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 жыл бұрын

Same bro, even I didn't get that

@nononnomonohjghdgdshrsrhsjgd Жыл бұрын

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

@aashwinsharma1859 4 жыл бұрын

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

@RedBar3D 9 жыл бұрын

Actually drawing them parallell seems to help understanding a whole lot

@4darekord 8 жыл бұрын

crystal clear explanation man

@jinks6887 7 жыл бұрын

really well explained thanks a lot ..love from india

@navarundas1878 6 жыл бұрын

great explanation..much appreciated!

@bondlets2342 8 жыл бұрын

Thank you so much! You guys are awesome!

@markren626 Жыл бұрын

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!

@RahulGupta-pf4yt 5 жыл бұрын

Your style of teaching is remarkable.

@hoangphamcong9230 7 жыл бұрын

realy clear! Love it

@luigiprz5319 3 жыл бұрын

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

@gracepancalstatela4422 8 жыл бұрын

best explanation!!! Thanks a lot .

@intesar6341 9 жыл бұрын

Thank you ... now its clear for me

@workingemail1016 3 жыл бұрын

Very well explained. Thank you.

@inku.1593 6 жыл бұрын

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 .

@1Rise 3 жыл бұрын

you explained the destructive concept perfectly and easy to understand.

@hokwanchan4142 4 жыл бұрын

the video gives me a clear idea of diffraction.thanks

@astroknight5 2 жыл бұрын

Beautifully illustrated!

@5vart5ol 6 жыл бұрын

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!

@angikmukherjee1226 7 жыл бұрын

You nailed it man!

@kushalchakrabarti240 5 жыл бұрын

This guy is great!

@tom_something 5 жыл бұрын

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.

@patrickneal9288 2 жыл бұрын

such a good explanation thank you !

@haristufail2121 8 жыл бұрын

Beautifully explained Sir.You should get a Noble prize.

@FDGod99 8 жыл бұрын

-_-"

@FDGod99 8 жыл бұрын

+Onkar Apte -_-"

@gracepancalstatela4422 8 жыл бұрын

I agree👍.

@LogicalCod 5 жыл бұрын

Nobel

@harrisabdullah2278 5 жыл бұрын

If there was a nobel prize for teaching

@tylerlitch3992 8 жыл бұрын

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

@jasonhng8135 8 жыл бұрын

nice video about diffraction grating!

@GoogleUser-ee8ro 8 ай бұрын

so clearly explained

@MohdSameer-rx9gj 3 жыл бұрын

Very very nicely explained.....!!

@banterbus4297 9 жыл бұрын

thanks so much you helped me understand it so much better

@Adrian24134 4 жыл бұрын

great explanations!

@udays6170 2 жыл бұрын

Beautiful explanation!

@vardanhovakimyan7633 5 жыл бұрын

good job, buddy! thanks

@lazyz8969 6 ай бұрын

Great Explanation

@aritramondal4010 5 жыл бұрын

Great video made all clear.

@ernstuzhansky Жыл бұрын

Great video!

@sayan_debnath 3 жыл бұрын

Great explanation.. Thank you

@mangatons 8 жыл бұрын

great vid!

@physestryshorts5214 9 күн бұрын

omg ..... no words for this lecture

@wooluke7144 Жыл бұрын

Wow. Very Well Done. All Capitals Letters.

@adreekazafor2410 3 жыл бұрын

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

@fahamidaani9597 6 жыл бұрын

wow you explain it so easily

@poiuwnwang7109 3 жыл бұрын

That makes sense to me, Khan.

@bhaveshohal3390 4 жыл бұрын

Excellent video.....

@mastersanjay7642 3 жыл бұрын

Amazing explanation and content hat tip

@sivasamymurugasamy3998 6 жыл бұрын

wow...wonderful..

@harshilkaswala1886 7 жыл бұрын

awesome Vedic loved it

@Cherrilady83 4 ай бұрын

God Blessed this man.. Tysm❤

@tajungnuksungpongen4339 7 жыл бұрын

thanks your AWESOME....

@bithipaul6810 5 жыл бұрын

Great video..sir..outstanding...

@vinaykumardaivajna2470 6 жыл бұрын

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

@yeonjin8 3 жыл бұрын

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

@ChanakyaVivekananda Жыл бұрын

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

@user-de2pm7vr7y 3 ай бұрын

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

@rachanamuralinarayanan7391 6 жыл бұрын

Brilliant!

@SohamChakraborty42069 3 жыл бұрын

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?

@redrocz1 7 жыл бұрын

great video!

@supersonic174 9 жыл бұрын

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.

@BlueRangeTV 3 жыл бұрын

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

@rishabhattri6055 6 жыл бұрын

Very well explained

@miyu6720 Жыл бұрын

khan academy saving my grades I FREAKING LOVE YOUUUU

@RealConSquared 9 жыл бұрын

grate vid!

@SkillSasaBoy123 7 жыл бұрын

Thanks so much for this

@antoniadukmenic627 4 жыл бұрын

Thank you sooooo much! 💞

@gabrieldobre8732 6 жыл бұрын

The best explanation

@craetydonutkey1348 3 жыл бұрын

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.

@aymenbk9138 3 жыл бұрын

thanks for this

@starcrosswongyl 7 жыл бұрын

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).