I built an acoustic LEVITATOR! Making liquid float on air

Ultrasonic levitation, IN YOUR HOME! Learn how an acoustic levitator works and how to make one.
You can learn more about your personal DNA story by going to 23andMe.com/physicsgirl
If you liked this video check out these:
Strange Sand Acts Like Liquid
• STRANGE Sand Acts Like...
BIZARRE spinning toys
• BIZARRE spinning toys
We followed the instructions for the acoustic levitator here:
www.instructables.com/id/Acous...
This video helps too:
• Acoustic Levitator DIY...
Subscribe to physics girl: kzbin.info_...
Creator: Dianna Cowern
Editing: Dianna Cowern and Jabril Ashe
Animations: Kyle Norby
KZbinrs who helped out with this video!
Léo Grasset (Dirty Biology)
/ @dirtybiology
Chris Ramsey
/ @chrisramsay52
Phillip Green
/ @philipgreenshow
Klein aber Hannah
/ @kleinaberhannah
Vanessa Hill (BrainCraft)
/ @braincraft
Thanks to Dan Walsh, Kyle Kitzmiller, Shona East and Asier Marzo!
physicsgirl.org/
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/ thephysicsgirl
/ thephysicsgirl
PO Box 9281
San Diego, CA 92169

[@unklepete276]

fyi, dogs hear 60khz, cats hear up to 64khz. Consider your pet's comfort when experimenting with this cool project.

[@benjaminjordan2330]

My dog loves it

[@xevilace01]

If you could hear this... What would it sound like?

[@prinshiahirwar5698]

We can just take a bat because it can hear upto 100s khz. Lol 😂😂😂

[@deepakjoshi823]

Can I make bats flee with it? Ufff...! They're tremendously irritating!

[@manipulativer]

@@deepakjoshi823 ye if you like insects more... or mosquitos ... myamy right

[@antivanti]

"Scientists, we do what we must because it's cool"

[@MySkeptic]

This is super cool!! As a former audio engineering student, it is brow beaten into you that standing waves are the enemy in the recording process. Really cool that they now have a crazy use for levitating small objects. Well explained and demonstrated!

[@nathangrey6892]

"And plus it's super cool, which i think should be the only prerequisite for doing science" - Physics Girl

[@Mr6Sinner]

“This is real, yo!”

[@Mr6Sinner]

Santiago F Umm.. 1. Why does it matter? 2. Why did my comment create this concern to you? Lol

[@gonbarrio]

Santiago F You care about?

[@placebo5466]

Jeeze, who pee'd in your acoustic levitator?

[@Mr6Sinner]

Gonzalo Barrio He asked if she is lesbian, but then deleted his comment.

[@pdrt2377]

Uriah Siner iii

[@wdbaudio]

Considering my field of study is acoustics, it was nice to see some coverage from your channel! I really enjoyed it

[@MrGodlikePro]

Username checks out

[@monoham1]

so can you lift bigger things then? how much would it cost?

[@enderkoregameing8090]

This is the craziest thing especially as someone who studies audio synthesis, amazing that there could be songs which make you levitate in some years

[@MichaelKubler-kublermdk]

That looks awesome and like something I could do. If I had a kid (and he/she was old enough) this would be an awesome bonding project. I loved seeing the plunger like one being turned upside down and the particle still being in place. That's pretty awesome!

[@Yurinsm]

I totally imagined a mosquito being trapped and trying to scape this levitation. OMG so much revenge

[@Szobiz]

Yuri Matias eeeeeeeviiiiiiilll

[@DudeBoerGaming]

@Alset Alokin He never perfected the art though

[@razvan092]

Good Idea ;)

[@IvanReuchon]

Yesssssss

[@yodatits8569]

I hope thats how future moskito traps work

[@rickseiden1]

Simone is going to be so upset that you didn't invite her over to help with this!

[@Eyerleth]

Oh geez, imagine what she'd do with it! "I made a robot that levitates tissues to your nose so you can blow it hands-free! Slight problem, the tissues tend to catch fire or accelerate to relativistic speeds."

[@sadhlife]

Eyerleth lmao

[@bobrobert6277]

Simone is cool but she's no physics girl.

[@jeffiscool1805]

I am soooo happy to see people once again wanting to build things with their own hands. Great video. Makes me want to dig out the soldering iron. Thanks

[@dineshjinjala1159]

I really like to see all your videos. Those all are just awesome. The way you explained, the way you talk about science, your passion for science, your expressions all are just wonderful. Thank you sister. These videos increasing my interest in physics.

[@adam7402]

Try using a schlieren devise to view the standing waves. May help with trouble shooting as well. Also try oobleck for it's sheer strengthening properties.

[@magneticflux7833]

Right you can actually see the light and dark bands and stacking beads is easy wtf is this garbage. I mean, they stack.. its not hard, they stack in the light lengths not the dark. Good call out.

[@Holobrine]

It's been done, but if you want, Veritasium has a Schlieren setup right now. kzbin.info/www/bejne/jqGxk6ycrd2ejac

[@adam7402]

Holobrine just watched this video, very cool.

[@TiagoTiagoT]

William Taylor, I don't think you know what you're talking about...

[@jonathanborthwick2964]

Cool idea! I fond this instructible. www.instructables.com/id/Schlieren-Imaging-How-to-see-air-flow/

[@Audio_Simon]

I wonder if focused ultra sonics could be applied in non-invasive surgery to manipulate things inside the body? (Maybe pinching off a source of bleeding in a difficult to reach place like the brain.) If each transducer is independently controlled, the phase and frequency can be manipulated to create the wave shape desired.

[@physicsgirl]

Check out ultrasonic cavitation in medical uses!

[@juandelapaz4122]

Simon Ashton it is.

[@juandelapaz4122]

Simon Ashton for kidney stones

[@a7dad822]

Aye, or somewhat irrelevant but just as cool "ultrasonic welding"

[@AtlasReburdened]

Well they use it to break up kidney stones if I'm not mistaken

[@markg9170]

Yeah! Dianna eres fascinante y eso se nota en cada video que realizas, gracias por compartir tu curiosidad y pasión por darle sentido a cuanto te rodea, enhorabuena y felicidades por todo el trabajo que realizan en tu canal! Cheers & Congrats, Curious Whisperer!!!

[@ammaretaki9797]

Girl .. this is awseom and all of your videos .. i'v downloaded them all almost.. keep going and give us the best😊

[@f4tornado450]

me: My entire dinner table is covered in plates and food and stuff, and I have nowhere to set my utensils when I'm done, so I have to hold them and stuff me in 40 years: * places fork in midair *

[@ZOOTSUITBEATNICK1]

imo I love that your vids are educational and fun simultaneously. You rock, DC. imo

[@ByRecentDesign]

This is the coolest DIY project I've seen in years. Thanks for sharing.

[@spectredivision8971]

Amazing..., Seeing people create such similar device... You guys are on a stepping stone to another means of energy source.

[@VintageTechie]

Oh all of us who watched the livestream know that the mic picks it up lmao

[@hajmola7605]

Account Name yeah 💩

[@InXLsisDeo]

I guess a high pitched constant buzz, especially annoying if you wear headphones. Because even though the waves are at 40kHz, the interferences are at much lower frequencies that can easily be picked up by the mic.

[@Kamel419]

I think given this may be something you run in to from time to time you may want to get or make a low pass filter for your mic... there are a lot of scenarios where unchecked hi freq can ruin a live broadcast, but it can also be removed in post easily with a low pass filter fortunately.

[@APiccolo]

@InXLsisDeo ...And it may also come to resonate with the microphone shell or other encasings as well. I'm not sure about this, but maybe the wavenumber of these waves in, say, aluminum, may get close to the dimensions of a standard mic

[@copycatshinobi6920]

Account Name original funtional name that your channel has

[@iamsleepyhollow]

I was there when you did the live stream and blasted the sound through the mic! 😂

[@user-zx5ot3wl8b]

That was awosme your show is really amazing God bless your amazing work💖💖

[@TheNinjonny]

Thanks for providing the link in the description! Can't wait to make this!

[@jasong2269]

absolute coolest channel on youtube

[@TheRolemodel1337]

try: codyslab pbsspacetime vsauce

[@carolynmmitchell2240]

this is far from the coolest channel.

[@taramas5582]

This is why I subbed

[@VPN14494]

Place that acoustic levitation contraption before schleiren photography setup. It's gonna be awesome

[@chanakyapendse7119]

One of the most amazing physics video i ever watched. Thank you physics girl

[@kyu4404]

Hi from the french alps.i discovered your channel thanxs to e-penser.very good job i love what you're doing!!keep going👍👍👍

[@MrMartinBigger]

Haha what a coincidence! We JUST finished building one this semester based off of Marzo's design! We got horizontal and vertical translation in the bowl design and levitated water, and graphite and a bunch of other stuff. Here's a short video I put up. kzbin.info/www/bejne/o2Oocn2JZc2eeqs If you ever get liquids working TRY SOAPY WATER, it's sooooooooooooooo cool! Repping Derek Muller's undergrad program! #QueensEngPhys

[@theHusky2490]

The reason microphones pick up the sound is because they need to sample at least twice the frequency of human hearing (usually 44,100 Hz) because of the Nyquist Theorem: B < fs/2 where B is the highest frequency of the source and fs is the sampling rate In short, if this isn't the case, expect aliasing.

[@raykent3211]

Ruben Yanez you've just given a good reason why the input signal to the sampling system should not exceed fs/2. Correct. But you say that this means that the microphone needs to respond to 2*fs. Wrong. You have mixed up multiplication with division.

[@theHusky2490]

Ray Kent it's 2*B < fs. fs is the sampling frequency *of* the microphone

[@jordanlapointe8207]

Ruben Yanez Bravo sir! I wasn't expecting to hear anybody use the Nyquist theorem outside of my (non)linear systems class.

[@APiccolo]

It depends too much. At the same time, a lot AD converters these days make an initial sampling with a way higher frequency, and only later downsample to the user value. Also, the pre processing may include low pass filters or not, which also makes this more relative

[@JeffreyMW1]

Your videos are so sweet! Thank you very much. I love you Physicsgirl!!! (I mean the physics part)

[@xGshikamaru]

Your enthusiasm is what makes this video awesome :)

[@rodneyowen1850]

Would you like to get back outside? How about a video on how sailboats can sail against the wind?

[@Eric14492]

How about a video on how the "slot effect" on a sailboat works? It's a much more interesting, and complex subject. The explanation many sailors believe is wrong, and even different aerospace engineers disagree on the correct explanation. It's fascinating, because sailmakers have made it work very well in practice, but apparently, we don’t fully understand how it works. I think you tell a great story about it.

[@RobertSzasz]

priest's son once you realize energy is extracted from the water and air's difference in velocity a lot of things that seem strange in sailing make more sense. You can do a lot of seemingly weird things so long as you interact with enough air, and water and your drag is low enough. (Foils or planing hulls are key as you would need a crazy long waterline for a displacement hull, drag/waterline length is another place wave interaction gets interesting)

[@crazygamezockerXD]

Robert Szasz my idea was that you just use Pythagoras Theorem to explain the higher speed as you can sail with an angle to the direction of the wind

[@dThineni]

How about a video on how a two plus b two equals c two? pewds sent me

[@shade9592]

priest's son Yes... That is quite interesting.

[@krishpatel8287]

Diana, You are awesome, do you plan on making apparel? Also, will you collaborate with Mark Rober? Along with that, are you coming to Canada soon? You have inspired me to want to become a physicist.

[@th3t1ck94]

Definitely enjoyed your video. I used it to levitate my obnoxious neighbors constantly barking dog. I wrote a program and it spun the dog around in the air until it shut up. I can finally sleep. Thank you so much.

[@shurjoaunibar]

Diana is my hero for physics. I watched literally every video she made.

[@buhlendzamela5553]

I was so salty when I watch this video because I thought I'll be the first to demonstrate this because I had a thought of this and I find out it's already a thing

[@GrainOfRice]

Does anybody else love his accent? 5:40 omg

[@nicolashudyma3767]

Grain Of Rice i was looking for clues in the comments to figure out where that guy's from. I think he's Spanish. I'm not sure though.

[@borcayven]

He is from Basque Country, a part of Spain.

[@Shadranat]

That's 100% spanish accent. He is from Pamplona, I think.

[@RedmarKerkhof]

Khajiit has wares, if you have coin.

[@lofim294]

I'm Spanish and defenetely that's a Spanish accent

[@MrDeclareWar]

My MRes project is Evaporation Dynamics and Fluid Flow in Acoustically Levitated Droplets so im really excited to use it.

[@carmenfregoso3131]

Thanks thanks thanks!!! ... for the instructions. Amazing video

[@ideegeniali]

Now make an acoustic screwdriver!

[@MilanKarakas]

OMG, you are using 72 transducers to get few beads of styrofoam to levitate?! I did it with single transducer, Attiny85 and some reflector. Did not tried to levitate liquid either - today later will buy hypodermic needle in order to make super small droplets of water, then will post video aside levitating styrofoam beads with single transducer. Thanks.

[@bennichols561]

And you did. Man of his word

[@rp6699]

awesome diana. love your work as much we love you

[@danmarquez3971]

Thank you!! I really enjoyed this video!

[@UltraWindow]

dogs should be able to hear those things, so consider your best budd.

[@marianneoelund2940]

It's at the limit of dog hearing, so it will depend on the individual. Cats, however, supposedly hear to 60KHz so it's not wise to run this in the presence of a cat.

[@Sumit-ch4ee]

Who is after Praveen Mohan sir's video

[@CrissCrash]

--

[@kranthiaryan6050]

Me😂 That guy introduced a new word to me

[@yashrudrakar7813]

I'm 😂

[@crazymog014]

D! I️ love your vids so much! You seem like would be such an awesome educator I️ would so take any course you teach.

[@beatmebeat]

A little tip concerning levitating water droplets: just use an aerosol dispenser. It'll create small enough droplets to be caught. Thank's for your amazing video and providing the links. It gave me some nice over Christmas activities :-)

[@aaronjennings8385]

Or water spray with food coloring

[@calebsherman886]

I can imagine hover-boards being really loud and annoying in Back to the Future.

[@rabbitpiet7182]

Caleb Sherman weren't they always?

[@kebakent]

"Sonoluminescence" Please do a video on it.

[@dharmathilakawalakuluarach2136]

@ Kebakent .Sonoluminescence is a phenomenon that occurs when a small gas bubble is acoustically suspended and periodically driven in a liquid solution at ultrasonic frequencies, resulting in bubble collapse, cavitation, and light emission. THIS IS WHAT Sonoluminescence means KEBAKENT . Well Yeah Dianna can you make a video about it plsssssss ... I AM YOUR SUBSCRIBER AS WELL I LOVE UR VIDEOS 😀😀

[@SpyridonJohn1633]

She reminds me of two of my high school teachers. My English Lit teacher, and my Chemistry teacher. Both awesome women!

[@CrazyCoupleDIY]

This is amazing, simply amazing I am going to use this in my next project

[@bernardo9726]

0:38 Is that Chris Ramsay?

[@physicsgirl]

Yes!

[@Draculapin]

where did you meet our favorite magician from Quebec ?

[@realitycheck7865]

Bernardo Oyervides, lol, exactly what I thought too 😁

[@danielragan8327]

I thought the same thing! I'm so proud of my boy Chris for knowing what acoustic levitation is!

[@ajee3229]

Oof

[@wilhelmdavel309]

3:40 Did anyone else hear: “You can test this out by being that weird person that yells at Kenyans.”? The video was playing in the background and without the picture context, “canyons” sounded like “Kenyans” to me for a second until I realised what she was saying.

[@briebel2684]

You are not alone. I was all, "wait, WHAT?" until I saw the visual. I guess I spend too much time visualizing everything in my head instead of trusting my eyes.

[@intheshell35ify]

I though Kenya just had a lot of canyons and she was being clever. Shut up, its legal to smoke weed now.

[@curtis6996]

😂So did I at first 😆

[@astronderbove]

One of the coolest videos on youtube I've ever seen.

[@dalenassar9152]

I think you can make the perfect 'bowl-shape' by pouring a hardening fluid into a large beaker, and spinning it until the fluid hardens. The focal point can be varied by rotation speed, density, viscosity, etc. You just have to find the right RPM, given the other parameter(s). Then insert the traducers on the hard parabolic-like bowl. --daLE

[@honorarymancunian7433]

How do you manage 3k views in under an hour? Je suis impressed!

[@jimsvideos7201]

3:57 You imply the existence of a quantum Slinky, and you've seen how badly entangled the normal ones get...

[@awesomeguy9573]

"Happy physicsing" God, I love Dianna

[@jacobopstad5483]

So cool! I want to see one like that single cone pointed down at the ground and levitating itself.

[@yourveryownexistentialcris9127]

YO I WANT HER T-SHIRT

[@parkerkincaid1031]

Did you catch what it says?

[@danielmona5944]

Seems like it's this one. www.qwertee.com/product/meaning-of-life-184

[@stevefink6000]

Really, yo, that shirt is "dope"

[@michaelstreich7734]

Styrofoam Hoverboards! NUFF SAID!

[@viveksoley]

That is really interesting. Earlier I did see some similar videos but it was more of a simulation of levitation using stroboscopic light. But this is real. Nice

[@ZeugmaP]

I have already heard about acoustic levitation before in a video, but it was in a lab. It's so cool that they made the DIY kit, I think acoustics is an underrated field of study. Also that's basically what I want to study, I'm currently in "Higher School Preparatory Classes" (CPGE in french) to become an engineer. It's a shame that not so much people actually know about acoustics. (when I say that I want to become an engineer in acoustics, they say "oh yeah like a sound engineer'" when it's completely different...) Sorry for the rambling, anyway that was a great video !

[@mark44901]

Okay this is gonna be a real stupid question but if you scaled up this tech, made it more powerful etc, could you use it to levitate itself by turning it upside down or would it just collapse down? I'm referring to the version that was only projecting/levitating one way, hopefully you get what I mean XD

[@agiff8690]

Yes personal sound levitation boots

[@jonsantos6056]

The technology has been around for centuries actually.

[@bowwing333]

Millenia*

[@jay-tbl]

How?

[@sauce8277]

EONS

[@arstino]

when you turned it i knew i needed one of these in my life

[@dylanparker130]

awesome work by the university of bristol - congratulations to them on their great job! would love it if more researchers reached out to Physics Girl to popularise their work

[@FreljilTheHungi]

3:39 "You can test this out by being that weird person that yells at Kenyans"

[@robogamer2023]

Freljil Hungi canyons

[@felixwinchester9256]

#THISISREAL_YO

[@brainmaangemore843]

just loving your vids

[@GlassDeviant]

Hey Phillip, haven't seen you since Got Talent, glad to see you're still doing interesting stuff. Gonna' follow your channel after this video is done.

[@GameLoverVivekrana]

I thought you are wonder women and when watched the full video finally you are :)

[@crackedemerald4930]

Call it an acoustic vice

[@aMulliganStew]

Like Vanilla Ice

[@greensteve9307]

Damn, that's good.

[@JerryRandalBauer]

Some advice: I'd advise you to call it a vise instead of vice, and not vice-versa.

[@rich1051414]

Acoustic immoral habit? Kinky...

[@charliefischer59]

Love how your parties are building science projects.

[@vritomos]

THIS IS SOOOO COOL!! Hey Diana, could you build a magnetic levitator next?!

[@jeremycbarnhart2305]

Greetings from 2020! Any possible chance you'll be revisiting this on a larger scale? Also, can the transducers be swapped with lasers to any effect?

[@terryendicott2939]

I'm afraid that your metaphors are not node worthy. sorry

[@stevec7923]

That deserves a standing wave ovation.

[@beth-rg8bm]

Love your videos!

[@jackleejonesjr.2995]

Dig the levitator.. I ask so many qs w u love ur 5 plus yrs ago stuff. Thank you for the Physicing

[@SavageRabbit666]

could this be a precursor to the sonic screwdriver ?

[@SavageRabbit666]

way to shatter a mans dream dude. way harsh, im gonna have to like cry in a corner for an hour thinking about your cruel comment,

[@SavageRabbit666]

really ? that's a bummer. maybe physics girl can figure that one out, she is way smart.

[@spaceguy4116]

what if you made a giant one and floated in it?

[@robinsparrow1618]

What if you made a giant one and floated a smaller one in it??

[@spaceguy4116]

Cajer1618 that would be interesting

[@crackedemerald4930]

Everything that isn't round is going to mess with the frequency and maybe break it

[@aMulliganStew]

encapsulate someone is a ball and then float them.

[@OzillionPlay]

I guess yo mama wouldn't have problems levitating then. Ha goteeem.

[@rogerhwerner6997]

Accoustic levitation has been around for longer than a few decades. An anthropologist made a film of Tibetan monks levitating stones over 80 ft to a cliff face during a building project using horns and drums. the film is published on the internet. This technique makes one wonder if it was used by the ancent monument builders to move megalithic stones. Interesting and very cool presentation.

[@greydef]

My niece and nephew are big fans of the channel and will be excited to hear that you came to our hometown!

[@XSpImmaLion]

Has anyone upscaled this to say... tweeter or subwoofer sized speakers and tried to see what the results would be? :P I mean, besides becoming deaf.

[@carolynmmitchell2240]

XSportSeeker I'm not 100% sure but I believe that's too low a frequency.. thats why they typically use quartz transducers to produce the sound.

[@SianaGearz]

I don't see what the issue is... i mean, obviously once you lower your frequency, you can no longer levitate tiny objects the size of a rice corn because the local pressure gradient is too low... but you should be able to levitate larger objects like gummy bears. You can get somewhat inexpensive tweeters and run them at 10 KHz. I see why they designed the kit this way, because you want it to be possible to ship in a mail envelope and cost only $20 in parts or less, and keep it safe, to actually make it accessible, but if someone wants to spend a few hundred to a grand and build one that is big and dangerous, i don't see why not?

[@ZenDude65]

Your hair is amazing

[@kennethsizer6217]

True. Making things float on focused sound waves is cool and all, but COULD HER HAIR BE ANY BETTER???

[@Mekratrig]

Aw. She got rid of the two tone hair, purple on the end.

[@5995Oblivion]

Came looking for this comment. I agree strongly

[@brianegendorf2023]

I have been dreaming of this for years. And he/you guys literallty do it the way I pictured. What I would love to see them do is build a sensor in that can determine when you've inserted matter, and then manipulate the node to lift that matter to a certain height, where it hits another group of transducers that are at a 90 degree angle that can "push" the matter out to a platform. I would imagine there is some way to regulate two varistors at each group of transducers to set the right amount of push each tranducer provides to control the ascent/desecent of the matter.

[@brianegendorf2023]

I was just thinking...as a safety measure, you'd want to create a backup plan in case someone was levitating and power went out. So if it doesnt interrupt or interfere with the nodes, there should be a ropeladder webbing up the shaft so that if power goes out, you can just quickly grab the ropes and climb out of there.

[@Parallax5x5]

You Rock! Love your work.

[@DeconvertedMan]

bigger speaker...levetate human?

[@blacksoulx2597]

Deconverted Man that’s what I said xD

[@blacksoulx2597]

Deconverted Man still that would be really cool

[@trejkaz]

Since the idea here is that it's applying a force by acting remotely via sound waves, I'd be wondering whether you could simulate something like a finger touching the back of your back, using speakers mounted some distance away from you

[@JohannesIhrler]

Also much lower frequency. With 40 kHz nodes are spaced about 4 mm apart. So you would probably tear a human apart. For nodes to be spaced 50 cm apart you'd need a frequency of about 340 Hz. It would probably still tear you apart though. And with such frequencies you'd also get problems with vibrations. But maybe in a few decades, it will be possible :D

[@stefanr8232]

6:39 Density was a limitation. So your personal levitator will only work if you are not dense. Also size really does matter.

[@yinvara9876]

Wait.. at 0:40 is that the guy from Britain's got talent?

[@physicsgirl]

YES! Philip Green. He's a fellow KZbinr.

[@daikengg3016]

He has a youtube channel on magic love him

[@anjanajames3976]

Great video Diana. Consider making a video on optical levitation.

[@robertparenton7470]

Thank You! Will buy one!

[@acess091]

Lol , in india about 1300 years ago our ancestors uses sound to lift stone blocks to build temple and those temples exist now in 2021 🙄🙄🙄🙄🙄🙄🙄

[@mathewraj3445]

Ya bro ,u r correct Temples like tanjai periakovil N some temples in tamilnadu Me tamilan 🔥🔥

[@acess091]

@@mathewraj3445 exactly bro

[@andreim841]

She is the complete package...

[@stevefink6000]

Except for saying "yo" a lot and, "dope", etc. Seems pretty insencere, but otherwise, love the brains.

[@GreeeenT]

yay I just got this for my friend for her birthday ! I hope she likes it

[@KumaBones]

You look super happy & excited... Really cool...!

[@zaza5042]

You have nice hands.

[@taramas5582]

Z sheesh you are a creep

[@HFn438hfgweiuwe98hHnfhjs]

I have a PhD in legos. I think I could make this in ten minutes!

[@HFn438hfgweiuwe98hHnfhjs]

In only legos? I have a PhD in legos and lego Duplos!

[@HFn438hfgweiuwe98hHnfhjs]

Lol dude lego duplos and legos are the same thing... get it right...

[@Spekter2500]

you forgot to change accounts

[@Szobiz]

Adrian Bard lol

[@monkeycucumber]

I learn so much from every one of your videos. Can you explain hypersonic directional speakers work like Soundlazer or Audio Spotlight?

[@dakotamercer1679]

So, I am just learning about standing waves and sound in my physics class. From my understanding, sound waves are actually longitudinal waves that travel through a medium. The description of standing waves uses transverse waves to explain it, but the idea is still the same. Correct me if I'm wrong please, but the nodes in which the material sits in are considered displacement nodes, where the particles of the medium do not move. This is related to pressure, as a place with displacement equals zero is effected by a max or min amount of pressure change. At displacement nodes, it is said to also be a pressure antinode, where delta P is max or min. To explain this concept, imagine the reason why displacement at this point is zero; you either have P_max, where all the particles around it are squeezing the node at both sides; or you have P_min, where the particles around it are being drawn away. You can see this idea at work at 5:05, where the maximum change in pressure causes the particle to be "squeezed" back into the displacement node. Let me know if I got it wrong!

[@dakotamercer1679]

I do not think I am thinking about this properly so any feedback would be appreciated! :)