The squeaky clean effect - the chinese spouting bowl

The chinese spouting bowl is a great demonstration of how friction can lead to resonance.
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[@EvanMoore]

What really interesting is that this vibrating characteristic is used to gather worms out of the ground. It's called worm grunting, and it is fascinating. My area's contribution to physics.

[@kamoroso94]

Evan Moore That's really cool. I've never heard of that before.

[@EvanMoore]

Fish feel the same way you do about worms. We grunt worms for fish bait.

[@TheGuardian163]

google it and found a KZbin video about it. Pretty interesting

[@CoolioHorseLover]

That reminds me of when they did that in Godzilla

[@JamUsagi]

If I remember right the worms think the vibrations are rain, so they come to the surface to take advantage of it... Not sure if I remember right though.

[@alwaysinformed1]

Doing that on carpet? You know what might happen Steve? Mould.

[@almerakbar]

Underrated comment.

[@ktaragorn]

@@almerakbar Didnt get it until i read yours first :D

[@KK-kg9hv]

Nice one

[@jeffborders5526]

Only the fifteenquadrillionth time he's heard that one I bet.

[@wbeaty]

Not just ripples, those are Faraday Surface Waves, a "soliton" wave which vibrates at HALF THE DRIVE FREQUENCY. Not a higher harmonic. Not traveling waves, instead they're an instability. Very weird. (It's like being able to hear ultrasound, by dividing the frequency in half.) Nonlinear acoustics of capillary surface waves. Also, the wave mechanics doesn't break down. Those Faraday waves actually are "chop," they're standing waves, and if the tops of the waves grow too high, little droplets are launched from the tips. Also, this is the same phenomenon behind foggers, sonic vape, Ultrasonic Nebulizers: all those little devices which hit the surface of water with a few watts of 1MHz ultrasound, which creates violent microscopic Faraday ripples, which launches sub-mm droplets. Also observe that the waves are at 90deg to the vibrating metal. Faraday Waves always do that. The bowl-rim vibrates in and out, while the Faraday waves act as "fingers" extending out from the metal surface. No bronze bowl needed: the same thing happens when you strike a half-full wine glass (or make the glass sing by rubbing with extremely clean scrubbed fingertips.) PS It's possible to make giant Faraday Waves in a swimming pool, using a flat board or a "pool noodle." Wiggle it fast. Rather than sending waves out across the pool, you'll get those "fingers" of oscillating "chop" which extend 90deg out from the moving plate.

[@T1NBANE]

Please make more videos! Your "Poor Man's Liquid Nitrogen" was INSPIRED.

[@pontifier]

Seriously... wbeaty was the first person I ever subscribed to... The reason I made an account way back in the day...

[@cxx23]

This comment is perfect.

[@kylezo]

Wow, this might be the first and only time I remark: "underrated comment".

[@shookings]

Tom Scott has done me a favor, by linking your video and channel. Great stuff

[@SteveMould]

+shookings thank you!

[@joeyverliesharen]

Steve Mould you're not the only one. I too came from Tom Scott. :D

[@aleattorium]

Me too, but it's interesting it started with "something you might not know"

[@anarbatzoriganar]

@@SteveMould link your resonance video to it as a card. they go together very well. cheers

[@stevethea5250]

@@anarbatzoriganar great idea

[@JWentu]

You know what? I just love the way you talk in the video, so calm and confident you could probably convince me of anything. Thankx for another interesting video. BTW, I came to know your channel through Tom Scott's.

[@SteveMould]

+JWentu thank you! Next video i will try and convince you the earth is flat.

[@Th3FatG0rilla]

Steve Mould hol up

[@adfaklsdjf]

I've gotta agree about the presentation voice. I'm in the States and I think there's also something about an English accent which conveys authority for many of us as well.. but I think the calm confidence contributes a lot. I came via standupmaths.

[@ABuffSeagull]

And this is exactly how percussionists do thumb rolls on a tambourine, or finger rolls on a timpani. Neat video!

[@kylezo]

Came here to comment this same thing!

[@RedHillian]

So glad I let the video run. Pouring squeaky noises from a beaker!

[@Goodwithwood69]

Any purpose to the bowl? Or its history? I'd enjoy a part two if it went into these details!

[@adfaklsdjf]

Someone else said it was used to gather worms? "worm grunting"?

[@orbik_fin]

For anyone who's interested, this phenomenon of repeated sticking and slipping is called ... the Stick-slip-phenomenon. It's also how violins and other bowed instruments work Also 1:38 - A complex geometrical object like the bowl probably has hundreds if not thousands of resonant modes with different frequencies. So in all likelihood, ANY squeaking sounds you get out of the handles is dictated by one of these resonances. Some modes are stronger (higher Q) than others and lead to higher amplitudes.

[@SteveMould]

+orbik thanks for the extra info. Great point about violins. Linking myself that it didn't mention that!

[@ratvomit874]

It does beg the question of whether there is a critical friction coefficient value above which two sliding surface do this, whereas they just slide smoothly for lower friction coefficients Anyone?

[@WakarimasenKa]

There used to be a shampoo comercial in German television that advertised squeaky clean hair. This also works for any soap, if you clean both the hair and hands.

[@manla8397]

The standard medium is water. However I wonder what will happen if oil is used instead. Some oil may have lower coefficient of friction but lower density. How about using acetone or silicone oil which can vary the density and sometimes if possible you may add a bit of detergent to change the surface tension.

[@Ttamlin]

Glad to see someone else sticking with their Pebble through all this. Best smart watch out there!

[@SteveMould]

+Matt Novak-Zarate mine is starting to do that screen tear thing :(. What am i going to do?!

[@Ttamlin]

Well... they're still available on Amazon here in the US. For stupid-cheap (what with Pebble having gone under and all)! I just bought a Time Steel for ~$90 shipped, to have as a backup for when this Time finally goes. (www.amazon.com/Pebble-Steel-Smartwatch-Android-Devices/dp/B011VB21DU/ref=sr_1_3?ie=UTF8&qid=1490284778&sr=8-3&keywords=pebble+time+steel) And, if you're really interested, there is a decent-sized group of developers out there in the world working on a truly open-source OS to run on these, with *most* of the functionality, for when FitBit eventually kills off all the server-based stuff. rebble.io

[@Trishlicious]

I loved playing with that bowl when I visited the science museum in Toronto.

[@KarlFFF]

That's a nice squeaky beaker you got there! :D Good as always Steve :)

[@Yistern]

I would love to see the sequence of the first few nodes of that bowl.

[@grossemann9721]

Did you try this with just one hand as well ? And would you reach the resonance frequency by moving your hands in opposite direction of each other?

[@Elec-DIY]

There is a huge spouting bowl in the Galleria dell'Accademia in Florence, if you play it correctly it gets so loud the security guards will come and tell you to stop.

[@SonOfFurzehatt]

Have you tried rubbing the handles at 90 degrees? It produces a higher note and a different pattern of ripples.

[@ALightInTheAutumnRain]

As kids we used to do that with the handrails at swimming pools. It gets really loud when you hit the resonance frequency. :D I've also been brought here by Tom Scott, by the way. Great channel! Subscribed. :)

[@FlorianFahrenberger]

So, I have watched through quite a few of your videos now, and I am really impressed. How do you find the time to do all those visualizations and builds in addition to the writing, filming and editing? I mean, there is no way you make any serious money from these views, so you obviously have another "day job"... right? Anyways, thanks for putting in this huge amount of effort, it's really fun seeing these. Looking forward to more.

[@SteveMould]

+Florian Fahrenberger than you! Not earning enough yet, you're right. Day job is doing live science shows.

[@FlorianFahrenberger]

Okay, so at least you can probably use those cool demonstrations in both jobs. :-) Good luck to you, I'll certainly forward your channel to teachers and science lovers I know. I myself watch it more for entertainment, since I don't teach and already have my physics PhD. :-) Best of luck to you!

[@SteveMould]

+Florian Fahrenberger quite right, they have a duel purpose!

[@teresalewis1]

Please collaborate with Dustin at Smarter Every Day! I would love to see that project!

[@adriannaj1711]

voice a documentary please

[@aidanwansbrough7495]

That's pretty cool! Love your explantation!

[@gracelozano1419]

would be interesting to see this demonstration in slow motion as well

[@TimothySchmidtMDPhD]

Does this explain why the friction between hands under an air drier decreases as the hands dry? More oil with drying?

[@wbeaty]

Watch carefully and notice that the ripples go the wrong way! They're perpedicular to the vibrating surface of the bowl.

[@AndreiStephan]

youtube poops the quality of the water jumpng like confetti

[@3enjoy3]

Haha, thank you Steve - all respect to the beaker!

[@hesham932]

your channel deserves 10m subscribers. at least

[@rucasolo5021]

And there was i thinking that you would then go on to demonstrate how the sonic vibrations and the water that they moved would truly clean dirty dishes. In the worlds of engines ultrasonic cleaning is very useful...

[@sheller153]

I like that you say "washing up liquid" while America just says "dish soap"

[@GglSux]

I think this would be really interesting to see on highspeed, the water spray that is, the rubbing hands ...not so much Best regards. (PS...the binge has begun..working my way backwards....DS)

[@SteveMould]

+GglSux i look forward to more comment then :)

[@trinityy-7]

is drag clicking/bolt clicking similar?

[@konchatzi]

The jumping and sticking motion would be good to see in slow motion..

[@davinator_peepo2102]

this is unbelievably amazing to watch while high

[@sean..L]

How many beakers do you own, approximately?

[@SteveMould]

+This guy at least 3 at any one time.

[@KingdomKillerKHNews]

only at 32 seconds but i could instantly tell it reacting to sound waves and vibration causing it to have that effect.... time to find oit if im correct

[@nathanvanmiddlesworthmedia844]

So...For anyone looking to buy one of these: Make sure when you get it to wipe the bars with rubbing alcohol before attempting to play!

[@this_is_japes7409]

so are particles just the result of wave dynamics breaking down in physics too?

[@jackester6742]

Why is one of your hands more yellow-brown than the other?

[@Guigui_82]

What was the original purpose of this bawl ?

[@athanoslee]

Guigui It is called 鱼洗， which means fish washer. But I suppose it was only designed as a toy with no practical purpose whatsoever.

[@kidderhellcraft6235]

I remember a vase or pot that cat do that but I don't remember the name

[@nathanselbach6185]

This isn't the only bowl he got

[@austinbryan6759]

When slo mo guys did this I think they did it the wrong way, their hands going in opposite directions hence why it was so loud

[@InvadersDie]

FUCK YES! ANOTHER VIDEO! SQUEEK SQUEEK!

[@tiagotiagot]

Can you shoot the water shooting up with a slowmo cam please?

[@saeedgnu]

We call those bowls "Istanbuli", I don't know why. Maybe they were imported from Istanbul ages ago.

[@KamakazeTaco]

"Washing up liquid" Dunno why I find that so funny.

[@Noone-of-your-Business]

Well, yeah, okay, I get how it works, but what is it *_used_* for? As a novelty? To check if you washed your hands properly? What?

[@SteveMould]

+None of your Business novelty.

[@landonkryger]

You can use the squeaky clean effect to test if you've washed your hair in the shower yet or not. If you have, it will squeak when you rub your hand over your hand. If you haven't, it won't.

[@code988yay]

Do the cup music

[@Saxshoe]

"When you hit the resonating frequency of something, the amplitude goes up"

[@andrea.dibiagio]

Are there cheaper versions?

[@FunnyMemes-dr3se]

Wouldn't the bowl handles burn your hands with the friction or something? Doesn't seem that comfortable.

[@FunnyMemes-dr3se]

Oh wait I was watching in sped up playback speed. It was going so fast that it looked like it would burn.

[@lukamilenkovic5097]

0:20 100% lawn mower

[@athanoslee]

It is called 鱼洗， which means fish washer. But I suppose it was only designed as a toy with no practical purpose whatsoever.

[@PatootyPanda]

Shit, one more video and I might have to subscribe

[@blubot7944]

"washing-up liquid" ...soap?

[@jazmin58]

this made me want to drink water

[@cabau3876]

I have one and can get the water to go up to 3 meters high

[@LikelyToBeEatenByAGrue]

There's a sex joke to be made at the end there, but I don't have the heart.

[@Yaxchilan]

It looks like an ultrasonic cleaner.

[@dickJohnsonpeter]

I was in jail once and I found out I could hit the resonating frequency of the cell with my voice. Suddenly at a specific tone it would become very loud and come from everywhere at once but only at that frequency. Yeah, there's not much else to do but experiment or read.

[@thePronto]

Those marketing guys: they are just professional liars...

[@a51mj12]

i dont think anyone was having difficulty understanding how this works

[@evanp25]

This dude look high asllll

[@matthewcecil8552]

The last scene in the video was weird, lol... You lonely?

[@SteveMould]

+Matthew Cecil my subscribers get upset if I don't pour something out of a beaker at some point in my videos. It's a long story.

[@kamoroso94]

Matthew Cecil It's an inside joke.

[@matthewcecil8552]

An inside joke about being creepy and lonely? lol. Is there a video that will add me to the inside of this joke?

[@matthewcecil8552]

I can see the emotions run high around here, hah. Cool video!

[@brianwyters2150]

I thought this was about people thinking they are clean but not.

[@vladislavkotenochkin3589]

Where slowmo???

[@peter007crouch]

Before I watch this video I wana know: Is there a beaker involved? If no - I'm not gona watch it!

[@Blox117]

i subscribed from tom scott's video :D

[@iidkwhatnameuse]

Tom Scott sent me here

[@JoyBoysWill]

My plates don't squeak FUCK

[@alejandronq645]

pour bowls from a beaker

[@Classsick101]

i was waiting for the " and chine's used this vibration to clean their clothes. :( they didn't? then what was the bowl for? it's very specific

[@B_Skizzle]

Nope, I don't believe it. You're clearly a waterbender.

[@mikeg6554]

My mother-in-law could never get this to work.....ya see, because she doesn't wash her hands.

[@Regolith]

why rae these showing up in my recommended

[@helikopter6071]

im supposed to be studying

[@celadoncity92]

Việt nam đầy

[@yamarati]

Kirk Cameron is doing weird stuff lately

[@Nicoder6884]

Gg🎸🎯🎯🚎🚎🚐🎸🚒🚜

[@FreedomAttacker1]

3:13 when she says it's her first time

[@gamehelp16]

Seeing the mini preview by hovering on the end of the video I thought you were pouring something, but after checking closely turns out you were doing something else. Disappointed :(

[@BlameItOnGreg]

gamehelp16 I guess he was merely pouring out your hopes and dreams.

[@youthere9396]

No Shit Sherlock

[@jake3938]

Him:"your hands naturally produce oil so you have to get rid of that" Me:"ok" *cuts my hands off*

[@SteveMould]

+Jake Ω ok, I chuckled.

[@wtfuredead]

*America has joined the chat*

[@vickielawson3114]

How do you cut off the second hand after you cut off the first? And then how do you type after that?

[@Alcyonidus]

@@vickielawson3114 asking the real questions here

[@U014B]

@@vickielawson3114 The same way you do with boxing gloves.

[@reDustt]

Can you demonstrate this in a microwave now?

[@Trollzzofficial]

I would like to see what he can come up with for that :D

[@Nicoder6884]

Trollzzofficial saa

[@nick5235]

Maybe Steve Mould could then follow up with a demonstration of how he can determine fake randomness from real randomness.

[@SteveMould]

+Nicholas R I hate you.

[@Rose-fz3xc]

Steve Mould - Science Videos in theory you should have a 50% chance of winning

[@Ibrahim-se6fy]

For some reason, I thought that the Chinese would put their dirty dishs in This bowl, and would rub the handles and the ripples would clean the dishs.

[@OphiuchiChannel]

Same... but the bowl is actually useless it seems.😶

[@kilrahvp]

Me too, ultrasonic cleaner style...

[@NoName_716]

Voyageur Very late reply, but the bowl was used by the Chinese Emperor to wash his face.

[@nu1x]

@@NoName_716 That's a roundabout way of washing your face

[@0riginOFinsanity]

Ngl, that would make doing the dishes more entertaining

[@KarlFFF]

Just realized! 3:12 That's not a squeaky beaker, it's squeaks being poured from a beaker 3:12

[@thePronto]

Now can we see the squeaks pouring themselves from a beaker while it is held upright?

[@stevethea5250]

@@thePronto I'm confused

[@gigglysamentz2021]

Did the bowl seller pay you ? =P

[@SteveMould]

+GiggitySam Entz no, I promise :)

[@gigglysamentz2021]

Ah okay thanks ^^ Did you pay for the bowl ? XD

[@coolmw2player]

GiggitySam Entz reply to him

[@tobiashenriksen7068]

Hot sounding water brought me here. (Freaky chinese bowl made me sub)

[@Mwak89]

How do you feel about the end of pebble? :(

[@harryjames5884]

Steve my surname is also mould so I am naturally wondering from what part of England you are from, we're from Northamptonshire.

[@SteveMould]

+Xx xX_BænslyHarriot_Xx xX Gateshead. But my dad is from down south.

[@KnowArt]

The slip effect even has a name! "Slip-stick" or "Stick-slip"

[@danbennett4192]

This effect can also be seen when you push a polystyrene (styrofoam) cup of liquid (coffee, say) across a table. Slow, careful movements will give you those standing wave patterns, and more aggressive movements will do the spouting thing. :)

[@williamreynolds6132]

I know this is an older video but I would love to see this as a collaboration video with the slow mo guys. Bet it would look amazing.

[@GpD79]

That's a good looking fella.

[@BigStuffedRhino]

from Tom scott

[@IrinaYin]

What a shame that I'm a Chinese but I don't know this 😂 Btw your talk today was incredible in Logan Hall !!!

[@manla8397]

Irinaldw 这个东西叫做龙洗，其实西方也有类似的东西，例如在酒杯迈用手指轻轻擦洗，也有类似效果。

[@NeyooxetuseiDreamer]

I bought mine in 1993 and have used it ever since as a sacred water bowl in my folk healing work with ritual and peoples healing. Its a great bowl to work with, even if you never use them to make water dance. Here is a photo of it and my water ritual this week... eldermountaindreaming.com/2018/04/15/slavic-washing-with-flowers-spring-ritual/