Light Is Waves: Crash Course Physics #39

The way light behaves can seem very counterintuitive, and many physicists would agree with that, but once you figure out light waves it all starts to make more sense! In this episode of Crash Course Physics, Shini shows us how we know that light exists as a wave and why that's really cool!
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[@crashcourse]

We made quiz questions to help you review the content in this episode! Find them on the free Crash Course App! Download it here for Apple Devices: apple.co/3d4eyZo Download it here for Android Devices: bit.ly/3TW06aP

[@Nihilnovus]

When I greet light, light waves back...

[@booboo8675]

EEEEEEEEEEEEEEEEEEEEEEEEEEEEEEY!

[@ZeeGhost713]

tragoedia veritas lol

[@Garfield7410]

*claps*

[@izzlez]

"studying waves has its ups and downs" 😂 I love this

[@ragepheonix3952]

This is driving me nuts!

[@darknightofthesoul8980]

A photon walks into a hotel lobby. They ask it if it wants help with its bag and it replies "no thanks I'm traveling light" 😁

[@flaming_mountain_spark2927]

funnnyy

[@ZeeGhost713]

Lol

[@timkohut1305]

Lol fungal

[@kennygerberich4985]

**gives four wedgies**

[@fossilfighters101]

Oh man Shini, I've learned this three times over two years, and this is the first time this has made any kind of sense to me. Thank you.

[@romelmorrison7581]

Even though it is above my grade level it still helps so when I go back to school i will be ahead of the class in some areas

[@Master_Therion]

Is light a particle or a wave? Or is it just *particularly wavy?* ;) joke, not a real question.

[@seggplant9455]

Master Therion both

[@jaydupree418]

Master Therion Light is a wave made of photons.

[@j.miguel6193]

well check the "double slit experiment" before you post videos... light can behave both ways... in another words, god exist

[@aajjeee]

are you serious when you say the wave particle duality implies god exist?

[@j.miguel6193]

+Barnesrino Kripperino yep not only me but einstein thinks the same... 'observer' the 'watcher'

[@sarinaadeline8811]

These videos are amazing, and they’ve totally saved me a handful of times during the mad dash that is summer physics!! I’ve found what works best for me is to watch the video, then read the corresponding textbook chapter, and then watch the video again. The first time watching it, it may not make too much sense. However, after reading the textbook chapter, it’s a super great way to gauge how much you understand and try to get a deeper/more dynamic understanding of the big concepts before moving to working some math problems. Good luck to all of the other physics students out there!!!

[@MI-lo2hj]

Hey ur voice travels at the speed of light😂😂😂😂😂

[@preciousnthabeleng3250]

True😂

[@supamayn17]

THANK YOU. I took a physics series and this was a perfect summing up of what I had learned about diffraction. I really needed a refresher.

[@howHumam]

I am almost paying more attention to how it was presented than the actual presentation, she's so focused and intense yet holds an edge of casualness in her tone that might encourage me to interrupt her had I the audacity. Good job, please keep teaching.

[@jarredc8929]

Whose quarantined and watching this for school?

[@madisonplays3756]

Me for science

[@samanthablackman4960]

you guys keep uploading stuff I'm learning at college 😂 from ethics to science 😂

[@Ph03n1X87]

Im learning at secondary school

[@notveryrea1]

@@Ph03n1X87 same

[@porygon-z4503]

Did I just see Enter the Gungeon!? In Crash Course!?

[@vitamindubya]

Porygon-Z omg! Obscure reference that I understand on popular show or media!

[@jwbman]

yup

[@eddiesanders2719]

In settings, I put the speed down to 1.5

[@brento2890]

Perfect explanation !!!! I just replicated it with my smartphone flashlight, and some books. Works exactly as stated.

[@StickyTank]

i once did the double slit experiment, using a laser-pen and some tin foil. i was amazed when it actually worked and created a beautiful interference pattern on my wall :D

[@qilinxue989]

Interesting! How specifically was it set up?

[@pivotman64]

Let it be known that the people behind Crash Course play Enter the Gungeon.

[@jacksonmorton4915]

YESSSS

[@FiniteMan1933]

Yeah dude

[@vonneely1977]

I keep waiting for her to take a breath but it never happens. o.O O.o O.O I, for one, welcome our new Smart-Bot overlords.

[@porygon-z4503]

Von Neely 4:51

[@Doc_Loc]

you fool we must fight agains the Overlords to become the new overlords

[@shaziashah8645]

Von Neely she's a skinny gurl

[@TuyuqVampram]

Breathing is for people with no editors.

[@geetika6540]

5:06. Well done

[@maryamalhamdan1510]

My favourite thing about crashcourse is their into music

[@yugeshkeluskar]

I was not able to understand this topic in my college and my exams are near. You put this video at the right time .... thank you so much crash course

[@magickisthekey]

Best explanation of the double-slit I have ever experienced! Thank you!!!!

[@nilsschroder9393]

I love this channel, keep up the great work :D

[@resqcreeper2]

love the ETG refrence

[@vnana2991]

Thank you for these videos!

[@nicolem2576]

very easy to understand. Thank you.

[@CorruptedN]

3:10 the single fact that the creators knew about this enemy in Enter The Gungeon implies that they got to at least the 3rd floor

[@G_Rad_Ski]

Ah, got to love waves without quantum probability

[@mohamedlotfi982]

great explanation!

[@adityashukla1507]

most awesome video keep it up guys

[@matthewhall319]

This is by far the best CrashCourse intro...

[@ketanpankey7633]

Great job

[@Laura-vs8rk]

so cool, thanks !

[@pikminlord343]

another great video

[@koyotemark4664]

WELL DONE!!

[@darthcomo8387]

I don't know what is the most beautiful here faced with awesome gods art including this narator

[@KyleCPM]

This could also be Refraction near the edges. Does the the coined light spot have a focal distance?

[@jessicaradford8564]

Oh man where was this three years ago when I did physics and was so totally lost on all of these experiments!

[@swastisolanki18]

Such a great video Wow

[@ayushaindas4948]

I love Crash Course

[@mrdfball]

You just taught me everything my teacher doesn't. Thanks

[@rkpetry]

(So many important questions on this topic)-Q#2. What about the shape of the photon envelope keeps it on, its course, predominantly, (most of the photon instances traveling across 'empty space'), instead of doing the single-slit-thing; Would that shape thin out...

[@dareenashgar1965]

Hello, I love your videos! Also, I was wondering which app do you use to make these amazing videos ?

[@raheenrana7430]

Great timing, I've got an exam on this.

[@srrex2696]

How hasn't anyone noticed the amazing Enter the Gungeun reference!?great vid btw

[@jedigecko06]

Finally I get it! Huygens' Principle explains diffraction!

[@romelmorrison7581]

This is good

[@maverick.gaurav]

Greaaaat video...super cool animations make things like these really easy to understand. which I'm sorry to say, books just can't deliver.

[@amitavpanda9118]

Amazing 👍👍👍👍👍

[@mazintareq3042]

Thank you for the clarification Gemayel we did not understand the subject in the school curriculum because of the old and backward Thank you

[@kennethhicks2113]

Classically good

[@rosecrux33star62]

I could watch her all day!

[@danukil7703]

Excellent video, you really have a gift for explaining these concepts to people like me who aren't mathematical and scientific geniuses :) On that note, Crash Course Calculus with Dr. Shini anyone?

[@MusiCaninesTheMusicalDogs]

She's so adorable it gets hard to pay attention to the content. 😍

[@jan-Juta]

Am I the only one who gets the "enter the gungeon" reference in the animation at the beginning

[@curmudgeon7217]

yes

[@jan-Juta]

XD good to know

[@luxurious0346]

Yehudah Goldstein no

[@LeonNikkidude]

Bring back John Green for more entertaining Crash course history.I like the way he jumped on that chair to reveal mystery object.He cynisism was very entertaining.

[@eddiesanders2719]

Actually, its cameras that work like eyes, rather than visa versa. Great presentation!

[@PinkChucky15]

Great video, definitely one of my favorite subjects :-)

[@bakadominus5668]

it would be really cool to use this to make light patterns in cathedrals

[@sarbjitkaur3301]

Short and meaningful videos. ☺☺☺☺

[@Intoxicatious]

Did you like the Enter the Gungeon reference? The game is on sale this weekend until January 30.

[@KatherinePierce_81]

Are you a paid actor

[@afishhouttawater]

Could you make a video explaining sign, cosign, and tangent?

[@ildikoki]

could you guys do a video on opaque materials and shadows?

[@philoyphilia]

A 30-minute lecture was given in less than 10 minutes. Light is proud of her.

[@PeacefulAnxiety]

Are you guys still planning on doing higher ed physics later on in 2017 or 2018?

[@3k.clipzz78]

Your good at this 😋😎😘😉

[@nicolasmirandacornejo2614]

Congrats, my university recommended us to watch this video before entering the laboratory experience.

[@Redemmo]

I've found CC Physics difficult because of its emphasis on equations. I enjoyed this episode more, with lots of theory (even if I'm still processing it) and little or no equations. I know you have your plans for the course, but I thought I'd offer a bit of constructive criticism :)

[@kickhuggy]

this idea still blows my mind, I can't wrap my brain around the idea of an object being a subset of one object and a completely different object without these two objects being part of each other.

[@Sporkabyte]

Spider-manana I guess the best way to think about it is to take a leaf from chemistry's book and not try to jam it into one definition we already know (referring to resonance here). Rather, it's better to think about light as neither a particle nor a wave, just something else that happens to have attributes of both. Hopefully that helps :)

[@undertow4874]

Oh my God. Enter The Gungeon!!!!!!!!!!!!!!!

[@Jaydoggy531]

I've been waiting so long for this video. Worth it!

[@nuwaralabdallat6660]

It sure is!!

[@rkpetry]

(So many important questions on this topic)- Q#1. If a photon is shortened to a quarter wavelength (in an advanced optics laboratory), what is its total wave-cycle-count length for when it passes through a Young's Double Slit experiment-Does it still show 10± lobes on the photoscreen, or is it fewer lobes, (try it)...

[@srilekhaf493]

Can crash kids make a another video and slowing down everything and explaining words and terms?

[@Gaia_Gaistar]

Light Wave sounds like a c-list DC villain the Teen Titans would fight.

[@thanhvutien]

Very nice video. Could anyone know which video tool to create this video animation? Thank you.

[@Lord_Unchemael]

2:50 Enter the Gungeon anyone?

[@rofernina8311]

Yep

[@christinamanis4351]

agreed

[@riffitup]

Hi.... great video. May I ask which software you use to create those animations?

[@leninirshad7395]

i just didnt get it in a full semester engineering.lady just explained soo effortlessly i regret the time i wasted

[@user-cj1dq4gf5d]

I've seen this before, I believed this rule that in fact Light s a wave. I even Conducted an experiment on this both the double slit and the coin and any spherical objects. they all work.:) However I wanna know why in most cases we cannot see that bright spot on the middle of a round shadow during a Lunar eclipse. does it have to do with the distance? roundness of the surface, in this case the moon and earth? wavelength of the light? earths atmosphere? Id love to know

[@Rookblunder]

So the shadow is actually two light waves cancelling each other out. Learnt something today. Or just can't remember that part. Thanks for video.

[@boxfish863]

Can you guys do a video on those Binomial wave videos. the ones where people claim their eye color and height changes?

[@a_little_bird]

LOL the sun at 6:30 is so cute

[@Mirsab]

im just studying waves, and light waves and light weight currently, perfect timing for the video Edit: I'm just studying waves and specifically light waves currently, perfect timing for the video. Sorry for the typo

[@Mirsab]

*light waves sorry for the confusion, it was just a typo

[@braxtonpal5842]

Really

[@merazulhasan402]

Unbelievably difficult !

[@issy2600]

PLEASE MAKE A CRASH COURSE MATHS 💕

[@nicdiculous]

It's interesting how a sizable amount of the comments are simply people trying to correct the video with their own opinion. I'm pretty sure Crash Course knows their stuff. So why act like you know things?

[@ibsizzle559]

wavyyyy *makes wave effect*

[@TazariaGaming]

I love how english speaking people pronounce things like the 'uy' in Huygens. It's actually pronounced the same way as the 'ui' in Kuiper from Kuiper's belt. For precise pronounciation Google translate 'onion' to Dutch and listen to the result.

[@amaranthine-one]

ENTER THE GUNGEON?

[@ProfessorYana]

Sure looks like it to me!

[@ZeeGhost713]

What is that?

[@empaulstube6947]

0.5 Playback really helps!

[@tenzin8773]

Is there a pdf's for the formulas that you mentioned in this course?

[@djbslectures]

Doesn't the presence or not of the bright spot in the middle of the shadow depend on some relationship between the wavelength and the diameter of the circle?

[@Kriegerdammerung]

Shini in the Mario's outfit is cute :3

[@sibongiseniarts9663]

Me in the morning of exam knowing that CrashCourse will break down the topic in 5min😅 it's good I now understand though 🕴️

[@tchikoumahmoud4665]

Your video just cleared the path for my billion dollar idea

[@randypullman1155]

my head exploded

[@caleblim6890]

"many of them thought light was a particle." I guess they're just particular about that

[@TheScientificCookie]

2:58 "Enter the dungeon" reference?

[@dipi71]

NASA’s Astronomy Picture of the Day 2018-10-02 _(»Supernumerary Rainbows over New Jersey«)_ sent me here. Cheers!

[@Personnenenparle]

PLease make a course on light polarity that would also explain polarisation filters! (sorry