Diffraction grating | Light waves | Physics | Khan Academy
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- Опубликовано: 6 июл 2014
- What happens when there's way more then two holes? Created by David SantoPietro.
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Grate video, must say.
Aly Azeemi great*
Chris Buckle Ik dude, it was a pun :p diffraction grate-ing. YES IM THE LORD OF ALL BAD PUNS.
Aly Azeemi ikr😂😂
TOP COMMENT WOWOWOOW, FeelsGoodMan :D
Dont grate on my nerves
Khan academy needs to keep you on board, your explanations and commentary style is a treat!
such a clear and concise voice
I don’t get why in the normal double slit it would be smudgy in the first place, why?
@@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.
Agreed
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If only my teacher at university could explain this in the way you did... thanks, now it looks much more easier to understand ;)
says who
10:55 "in between you'll get *darkness* "
me: I know...
*turns off light, sits at the corner and falls into depression*
Mr. J_Krr_ :(
A whole mood
sed lyf
4:03 .. how about a third hole? This is where it gets interesting... LMAO
😂😂😂😂😂
Brother,😂
Mouth..vagina...&...... The thid....
2:12 "Why? Well, lets talk about why."
LOL, reminded me of the GMM quote, "Lets talk about that".
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.
Who are you so wise in the ways of science?
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.
How does that magical spot even exist mathematically
you just explained a full lecture in 15 minutes, and beautifully and simply. bless you.
"And in between these bright spots you will get darkness...which is grate."
I don’t get why in the normal double slit it would be smudgy in the first place, why?
Fluffz Xx cause the waves won’t completely cancel out in between, partial destructive or constructive interference
I barely understood the idea of diffraction grating until I watched this!
Thanks for the help
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!
All David’s videos on physics has been absolutely amazing!
Gosh!! Such an awesome and clear explanation. Jazakallah Khair.
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
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...
many thanks man. it's clear that you really want to explain the subject and you do it perfectly!! well done!!
Never understood what the concept was before but this was like magic.. well done and thank you so very much.
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.
Same bro, even I didn't get that
@@adityamathur5972 i was scrolling through the comments to find that question and some explanation
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!
You did such a great job explaining! So clear and easy!
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.
This guy is like a young sassy Sal Haha. Love it thank you for the videos.
Its Great. Mind blowing. Top class video.
Thank you very much for teaching this
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.
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!
This explanation is very clear. I read my physics book on this topic, and added with this video, it makes sense! Thanks
Thank you so much! your videos on diffraction and the slit experiment really helped me fully conceptually understand the process.
Just understood the concept in 15 min which I couldn't understand in days. Great explanation
It helped me understand x- ray diffraction.. thank you.
I understood that very well. Great job sir thank u very much!
What screen recording software do you use? I would like to know a good one that allows me to pause recording.
khan academy saving my grades I FREAKING LOVE YOUUUU
Your style of teaching is remarkable.
omg ..... no words for this lecture
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 .
so comprehensive! thank you!
That;s incredible. Thank you for your work
The explanation is very clear, thank you
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!
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?
i think i don't even need to go through the topic anymore thanks
really well explained thanks a lot ..love from india
Wow. Very Well Done. All Capitals Letters.
2024 and this video still working great 😃👍 thx for the explanation you're doing amazing!
Where's the love button?
thanks bro you've helped me alot!!
Beautifully explained Sir.You should get a Noble prize.
-_-"
+Onkar Apte -_-"
I agree👍.
Nobel
If there was a nobel prize for teaching
Actually drawing them parallell seems to help understanding a whole lot
wow..that is amazing, thanks alot!
Mannnnnnnn This is such a good explanation!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!
great explanation..much appreciated!
Very very nicely explained.....!!
Thank you ... now its clear for me
Very well explained. Thank you.
crystal clear explanation man
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).
God Blessed this man.. Tysm❤
This videos are just amazing!
you explained the destructive concept perfectly and easy to understand.
That makes sense to me, Khan.
Thank you for making this video. 🙏🙏🙏🙏🙏🙏🙏🙏🙏🙏🙏🙏🙏🙏🙏🙏🙏🙏🙏🙏🙏🙏🙏🙏🙏🙏🙏🙏🙏🙏🙏🙏🙏🙏🙏🙏🙏🙏🙏🙏🙏🙏
Great Explanation
Would you please help me telling me that in which video you derived "d sin theta equals to del x"?
Thank you so much! You guys are awesome!
best explanation!!! Thanks a lot .
the video gives me a clear idea of diffraction.thanks
so clearly explained
First time watching an English explaination but still it's so good❤️👍
Id like. To know what program you used..thanx again
Great video!
This guy is great!
Beautifully illustrated!
Amazing explanation and content hat tip
nice video about diffraction grating!
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.
realy clear! Love it
good job, buddy! thanks
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.
You nailed it man!
Thanks, the Bulgarian student books don't explain this well at all!
Finally understood it
Excellent video.....
such a good explanation thank you !
Beautiful explanation!
Great explanation.. Thank you
thanks so much you helped me understand it so much better
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.
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 ?
easier than reading a textbook. Thanks!
Sir please tell me why we use grating lens in numerical aperture but in Newtown rings we use glass plate
Great video made all clear.
Great video..sir..outstanding...
great explanations!
awesome Vedic loved it
Quite a marvellous experiment and of great utility, as the instructor points out and I rightfully admit. However, as opposed to YDSE, wouldn't this experiment be a nightmare to actually execute? We are dealing in lambdas of the order of below microns here, so in the process of exacting our Ds across the wall, even if we miss the mark by a nanometer in making the hole we might mess up the whole pattern right? In YDSE we didn't have such a concern since there were only 2 holes so a slight error would only cause a slight shift in the interference pattern, but for diffraction grating wouldn't the error add up due to all holes and effectively yet a dark spot instead of a bright one all because of physical imperfections?
I got it the first time only thanks to your explanation
ELITE TEACHING SKILLS
reflective grating vid would be dope
does that mean that the size of the dot correlates to the wave's amplitude?
I dont get the thing of the cycle. What is your assumption on this wave cycle?