Interference, Reflection, and Diffraction

Light and sound waves do all kinds of cool stuff, because they can be in the same place at the same time, unlike matter. This creates patterns that are important to understand! Let's take a look at interference, reflection, and diffraction.
Wave simulator: phet.colorado....
Watch the whole Classical Physics playlist: bit.ly/ProfDave...
Modern Physics Tutorials: bit.ly/ProfDave...
Mathematics Tutorials: bit.ly/ProfDave...
General Chemistry Tutorials: bit.ly/ProfDave...
Organic Chemistry Tutorials: bit.ly/ProfDave...
Biochemistry Tutorials: bit.ly/ProfDave...
Biology Tutorials: bit.ly/ProfDaveBio
EMAIL► [e-mail]
PATREON► / professordaveexplains
Check out "Is This Wi-Fi Organic?", my book on disarming pseudoscience!
Amazon: amzn.to/2HtNpVH
Bookshop: bit.ly/39cKADM
Barnes and Noble: bit.ly/3pUjmrn
Book Depository: bit.ly/3aOVDlT

[@mariamomar9694]

Am I the only who ALWAYS sings along with the intro song?! It's so ICONIC! Makes me excited for the video.

[@temisola2163]

you’re not 😭😭😭

[@zafroo5042]

Mee too 🤣😁

[@venkateshchakrahari5832]

Count me in 😅😅

[@christine1401]

you're not alone 😆😆

[@emiliehannibal2895]

oh my gosh!!! thought I were the only one

[@thomascal3401]

From Calc 3 to Physics 1a, nice to watch 5-10 minute videos rather than 30. Thank you prof Dave

[@retsepilemothepu1396]

My Physics improved from 50% on semester test 1 to 97% on semester test 2🎉🎉
Thank you sir, I have nothing to offer. I’ll thank you properly in the future.

[@lucapetrescu6990]

Thank you Physics Jesus

[@movpod5901]

Literally looks like Jesus lol

[@z3nkin]

@@movpod5901 so you're telling me jesus is a white man.

[@reman3000]

@@z3nkin no of course he's fucking blue

[@Aethelhadas]

i sleep lol

[@faritcaart9273]

Prophet of juses love

[@illuminatedslug]

my man’s is gonna have the last supper after this LMAO

[@ARCSTREAMS]

rofl

[@hadeerrashad5486]

thanks a lot professor Dave for your amazing video!

[@Aurelia03118]

I got one of the best science explanation channel... ✨
Appreciation from India🇮🇳...here's ur one more student😊🙏🏻

[@330MillionGods]

2:22 when the wave is opposite phase and both waves are travelling in *opposite* direction , waves do not cancel out each other but they form a stationary wave. Waves will cancel out only when they are traveling in *same* direction.

[@ahmedatifabrar7698]

They may cancel out each other. Please watch Walter Lewin's lecture on Resonance. Standing wave is the net result we behold. But the waves cancel out each other between the positive maximum and negative maximum amplitude (think of a fundamental frequency wave).

[@asif-uz-zamankhan937]

Thank you sir.... Respect from your online student from Bangladesh!!!! May God bless you sir.... অসংখ্য ধন্যবাদ স্যার, আপনার প্রতি রইলো শ্রদ্ধা। সৃষ্টিকর্তা আপনার ভালো করুক।

[@moshiurrifat6935]

😎😎😎

[@rifatkhan192]

bangladeshi here brother.

[@sandroca18]

I loved this explanation! Thank you! It opened my mind to so many things. I meditate for the last 5 years, and I have heard so many videos about our body frequency, how to raise our vibration, how we interfere in each other with our energy. Why we like some people right the way, while others, we do not like. And now listening to this video, I start to think, we are atoms, energy, we are waves and particles at the same time, so we interfere with each other creating constructive and destructive waves. It blowed my mind to understand us in terms of physics, in a microscopic level. Also there are so many videos here in you tube of healing music to heal all kinds of emotional and physical disturbances, to decrease anxiety, lower blood pressure, improve sleep, etc, music affects us with its sound vibration, and the vibration of songs interfere in the water of our bodies.

[@耔函周]

Can't stop laughing 🤣

[@tamannagoyal8385]

Too informative,easy to understand....thanks for such video

[@gursikhichannel7282]

First best video on YDSE I ever found on youtube. Thats great.

[@yogawithcarlos]

I'm not being picky, just trying to learn. I thought difraction was pronounced 'dee..' as in DI-ferrent. thanks for the video

[@theaveragemegaguy]

I believe it is. Not dyefactrion like he says it

[@horsebiscuityt6135]

Super useful, thank you!

[@gopikrishnank1956]

Nice video sir...very helpful...Thanks you..

[@emaanasif4481]

Thank u Professor Dave

[@jesslyn5081]

Professor Dave can u record a tutorial explaining optics (ray diagram , thin-lens&magnification) ?plsss I need u

[@downandout9753]

succinct yet clear. He's seems to posses a deep understanding of the subjects; which I hope I'll someday achieve.

[@marq6325]

He’s literally jesus

[@mirtyunjaytharu1181]

1. Constructive interference
2. Destructive interference

[@Rahuljoshi008]

right!

[@dharnalapallamraju2654]

Respect you sir from andhrapradesh(india)

[@Whyulookingbruh]

Wtf why are u telling us where ur from

[@thayhuongchuyenhoalekhietq6803]

Excellent, Prof. Dave

[@brandonalcera]

Thanks I had a quiz on this this morning, really solidified my understanding

[@islamhany6986]

Thanks a lot professor Dave!

[@itsmaryam3378]

By far the best video

[@animeshkoyande4934]

thank you professor

[@Matescium]

Great explanation

[@arjunbabumabuhang4056]

Thank u sir. Love from Nepal😍😍😍

[@aakankshaojha6810]

Np❤

[@mark270five]

0:39 “Because of a thing called physics” -LeMillion

[@AnjaliSharma-ur2oh]

It's amazing.... clearly explained everything in just few minutes .

[@danielmacfarlane4575]

Thanks Dave this was helpful and short.

[@gachaami9542]

Thank you so much!

[@itsfarhan5480]

Thank u Professir Dave.
Love from KSA

[@roschelledimentman2768]

thank you so much! i just learned a ton in just a few minutes

[@HarshRajAlwaysfree]

Hey prof, daveCan u plz make a video on equation of waves.And show its applications on different waves

[@sebastian7494]

Thanks a bunch, Professor! You are awesome

[@windyzanele3813]

thank you professor you are amazing from high school till varsity ✊

[@hamnakhan9298]

It would be awesome if you also went thru newtons method for calculation of the speed of sound and laplaces correction!!!

[@RezaNoorzehi-r5h]

thanks a million professor Dave!

[@puppalasisira]

This topic is interesting, explanation from dave sir is much more interesting. Thank you sir

[@fenrir834]

i don't understand what is the use of this video, it just gave an extremly superfecial overview of the topic.

[@jordango6716]

Amazing tutorial!

[@thehyperbolicintegral]

Sir, you are a great help!

[@dodatkidominecrafta4762]

you're much better than tutorials in my native language

[@abdulyusuf6458]

Prof u'a actually amazing. U clarify in short time marvelous. Buh it gonna if u can attach calculations

[@БаянурДжороева]

Thank you(:) You are great phisician-teacher😊 Videos are 👍

[@mohsinali534]

With due respect its physicist not physician! :-)

[@teosticea2388]

You sir. You are a legend.

[@angeliemaebonaobra4448]

Professor Dave! THANK YOU!

[@preethi6370]

Thanks Dave, it would be better if you could relate it with the properties of light 😀

[@waqasayub5803]

Very helpful tutorial this video clear all the confusions i face in these topics :)

[@Richard___554o]

Hi, I've got some amazing news that you'll be thrilled to hear!

[@luckyprosperity6408]

love this explanation better than my prof's

[@brenomunoz9588]

¡Gracias!

[@SameerSk]

Many many thanks sir

[@codedaily365]

wheres ur modern phy course? i was here for difraction part only

[@Gk_1234-t2z]

Thanks sir😄
Your One more subscriber
Love from India 🇮🇳.

[@FantasticFanta227]

Constructive interference and destructive interference 5:28

[@perceptionshare2248]

Great video. Thank you for sharing your perception.

[@PovaSlemani]

Thank you too much professor Dave i understood now😊😊

[@blueckaym]

1st) In the case of destructive pulse interference, when in the segment where the two pulses interfere destructively what's the thing that causes each pulse to continue on its way?
I know it happens, but I have no idea why. If I try to think about it there's a segment where the two pulses energies were destroyed, so it seems like they shouldn't be able to propagate after that.
It's the same with constructive interference of course, but in that case at least there's the energy in the twice-as-high peak that would carry on the momentum.
But what carries the momentum in the case of destructive interference?
And 2nd question ~ 4:34 you mention diffraction of a wave thru a slit. You also mention that the produced (circular) diffraction is kind of interference pattern, but if the diffracted circular wave still only have uninterrupted sequence of peaks & valleys isn't it just a wave that just spread its propagation direction (just like a stone in a lake produced circular waves).
But the main question is, in a simpler case - light in vacuum meets not a slit, but just one edge (imagine it like the razor's edge in Schlieren photography) light would still diffract on that edge and would start spreading in circular direction behind the obstacle ... but why?
Also isn't the slit scenario just a case with two (close) edges diffraction, and the interference that we might observe is the interference between the two produced circular waves (with centers offset by the distance between the edges)?
And if so, isn't the spread of light behind a narrow slit just the effect of that diffraction (& interference) and not (as many people claim) caused by Heisenberg Uncertainty Principle - that making the position of light more precise (by narrowing the slit) results in higher spread of its momentum?
If the HUP people are still correct, then how would you explain the light from a nano-laser? I see currently some of the smallest nano-lasers are between 50 and 150 nm, which is considerably smaller than most slits used in said demonstrations. Certainly having the position fixed several times narrower would produce even higher spread of light? ... but it doesn't.
My whole point on the HUP-aspect of light thru narrow slit is that it's a produce of diffraction on obstacles and not result of us knowing anything about it.
If you really think about it, we KNOW that a light in a beam is made of many, many photons travelling in coherent linear manner. Hence if we just select to consider one of these photons in the whole beam we know it'll travel in straight line (if it doesn't interact with anything else), so how would that precise knowledge (about a position of a photon) cause it to spread (w/o hitting anything and travelling in vacuum)?
I know of the described phenomena, I'm just trying to understand them as much as possible.
Thank you!

[@swapnilpatil8117]

Very helpful🙏🙏🙏

[@selfhelphero]

Thank you

[@jaredreigns988]

Pov: exam is tomorrow

[@Reebosters]

Exam is tomorrow morning and it 1:02 am I fuck my self on this yt channel o***** completed

[@matthewhays8265]

How come you didn't rightfully say Huygens Principle when explaining diffraction?

[@Champagne_confetti00797]

Thanks Dave😊

[@ahmedalrafi500]

Awesome video 👍

[@AzizbekAbubakirov-g3b]

Thanks very much

[@richasharma864]

Nice teacher

[@razasyed575]

amazing explanation

[@EllaAnthony-en2fp]

Professor,, can you please make a full physics cores please!!!
I have searched for it but I can't find any except chemistry and biology

[@thehitmanhimself6794]

He explained it better than any other teacher out there

[@mayarzamzami]

thank you physics king

[@faithchama5907]

What's the importance ot the main purpose of learning or studying double slit diffraction??

[@ashutoshsinghindian6175]

Thanks sir

[@thamaraithenral.b22]

And you are very good in teaching sir and I like it very much🎉😊

[@AmitVerma-mi9rj]

U are very good in teaching.

[@minatsukinana2761]

hello professor, I wanna ask a qst ... what is the phase ? can you give me the definition ??

[@diggingDwarf]

Phase is just a reference to understand by how much angle one wave is ahead or lagging behind the other wave...

[@tamia8040]

U are a life saver ❤

[@AL-le7nr]

THANK YOU professor

[@tubeverse911]

Is it possible to interfere 1310nm wavelength in medium?

[@aswathyb6859]

Thank you sir

[@ramshresthgope]

Thaks sir

[@gracehu3031]

thank you so much!!

[@jikkujose4235]

thanks a looootttt very very usefulll

[@g.hrishikeshsrichaitanya6c538]

Thankyou so much sir

[@dhyanlunechiya8738]

Great content

[@getitorforgetit9231]

Hatss off sir simple yet crisp

[@henrikpedersen533]

Mega god Video, elsker dine videoer babe

[@princeshaufiku4975]

Thank you, God bless you 💕

[@mananwashere]

THANK YOU SO MUCH

[@Khgxcji]

Respect you sir.From Pakistan. :)

[@merikavitamerevichar9988]

sir BA means bachelor of arts so why are you saying that you received BA in chemistry .

[@Lucky10279]

This guy is so good at explaining stuff.

[@PovaSlemani]

Iam watching you from kurdistan bravo master ❤❤❤❤❤

[@filmsy1721]

Thanks Avi

[@aashishkulkarni2499]

Can we observe Doppler effect in space?
P.S I'm still kinda confused with the equations and formulas in Doppler effect

[@ProfessorDaveExplains]

sure, just not with sound! we see it with light, red shift/blue shift is how we know the galaxies are receding from one another

[@aashishkulkarni2499]

Professor Dave Explains But there isnt a medium in space, so does that mean we can't here sound at all or Doppler effect doesn't work in space?

[@ProfessorDaveExplains]

yes, there is no sound in space, as sound requires a medium within which to travel. light does not, light can travel in a vacuum, so we can exhibit the doppler effect for light.

[@aashishkulkarni2499]

Thx a lot Professor Dave :)

[@Raghav1205]

Can you consider making videos on electric charges at rest( electrostatics )?

[@ProfessorDaveExplains]

electricity stuff coming next week!

[@samanthakeilyn5927]

You saved me I don't know what to say Tom but now I know thank you so much

[@ayahal-athwari8631]

dave

[@abdulkalamabdulkalam2624]

Very thankyou sir

[@zinneerahsalim2964]

Thanks sir🙂

[@janelsamuels8411]

Thank u so much sir