The Truth About Toilet Swirl - Northern Hemisphere

  • Added:  2 years ago
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    Some notes about this.
    We each repeated the experiment 3 times, and got the same results every time. For those of you who might be skeptical, great! The good news is that right circularly prismatic kiddie pools are only $10 and you can do the experiment for yourself at your latitude. There's really no reason you shouldn't do this on your own, so before you criticize how we've done it, I'd strongly encourage you to do it for yourself.

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    Gordon McGladdery did all of the sound design for the video. We used two songs from other artists (licensed of course). Derek split the first one up so it fades from video to video, and Gordon split the instruments up on the second one. There are violins on one video and percussion on the other for example. It's really neat.

    The neat earth animation at the beginning and the synchronizing timer was made by He also made still images of the earth from the top and the bottom.

    Thanks to Jacob Vehrs for helping make the plywood pool platform.


    There was a study performed at MIT years ago ( that explained the physics involved. We repeated some of these demonstrations, but on opposite sides of the globe…and in a way that can be easily understood.
    This site is a great resource on the Coriolis effect and ways people have gotten it wrong:

    The Coriolis Effect influences the flight of a bullet.

    We would love for someone to replicate this demonstration. Please tweet your results to us @SmarterEveryDay and @Veritasium.
    Here's the link to puchase the exact same pool:

    Tweet ideas to me @SmarterEveryDay

    The thought is it will help educate the world as a whole, and one day generate enough revenue to pay for the kids' education. Until then if you appreciate what you've learned in this video and the effort that went in to it, please SHARE THE VIDEO!

    If you REALLY liked it, feel free to pitch a few dollars towards their college fund by clicking here:

    Warm Regards,

  • Video CategoriesScience & Technology
  • Runtime: 8:2
  • Tags for this video:  Smarter  Every  Day  Science  Physics  youtube edu  Education  Math  Smarter Every Day  experiment  nature  demonstration  slow  motion  slow motion  education  math  science  science education  be smart  edu science  what is science  Physics of  projects  experiments  science projects  coriolis effect  toilet swirl  australia  Coriolis  Fluid Dynamics  

Comments: 5 669

  • random human
    random human 1 day ago

    i read it as Taylor swift 😅

  • NasToy
    NasToy 1 day ago

    I placed the videos on the wrong side of eachother, so the end where you go to the other guys camera, it just looked weird.

  • lee guankiat
    lee guankiat 4 days ago

    I am going against everyone in the world. The earth is concaved.

  • The TomFoolery Of The International Space Stage

    I recreated your experiment and failed to get a anti clockwise rotation.

    Do you really think you can detect the spin of he earth with a kiddy pool in your shed lulz?

    The "Truth" About Toilet Swirls - Destin Sandlin and Veritasium Coriolis Experiment #1

  • Brad Lamont
    Brad Lamont 7 days ago

    that was sick

  • Xanthopteryx
    Xanthopteryx 10 days ago

    Your explanation of the the coriolis effect is not quite right, unfortunately.

  • Lamar Shealey
    Lamar Shealey 11 days ago

    you have to do this it is cool

  • teo_B_boy
    teo_B_boy 14 days ago

    So if the earth wasn't rotating the water won't be spinning at all

  • Joey Finton
    Joey Finton 14 days ago

    What if you did this on the equator?

  • Ben Kissell
    Ben Kissell 17 days ago

    This is the best vid ever

  • John Larrabee
    John Larrabee 20 days ago

    this was genius

  • Daniel George
    Daniel George 26 days ago

    Wow that was just amazing :)

  • Tim Evanchick
    Tim Evanchick 26 days ago

    That was super awesome!

  • Bdr Jde
    Bdr Jde 26 days ago

    I wonder how the Coriolis effect applies to "toilet swirl" if you were to centralize the drain over one of the poles. I think it would be cool to see visualized instead of assumed or accepted in theory.

  • Harold Westrich
    Harold Westrich 26 days ago

    I like the way you describe it but I think you should add that in any system, like a pool or toilet, the Coriolis effect works based on THAT small system and the much larger system, of the earth, is not as effective on the tiny condensed water system. In other words; small water systems are far more effected by local motions such as momentum added through filling of the container or pulling of the plug or deflection of drain guards etc. etc, etc. My way of thinking about it is the same as you would see an ice skater spinning with arms extended, then when they pull their arms into their bodies their rotation increases greatly. It's the same way a Tesla turbine increases speed as fluid from slow outer diameter approaches the center exhaust port.

    • Harold Westrich
      Harold Westrich 26 days ago

      Examples of things that take advantage of Coriolis effect: Tesla Turbine, Spinning Dancers, Swimmers on inner tubes who pull arms and legs in to spin faster! Tether ball when string wraps around pole.

  • Jusonn99
    Jusonn99 28 days ago

    which way does it spin directly on the equator?

  • pecfree
    pecfree 28 days ago


  • Chad Kennow
    Chad Kennow 1 month ago

    This was awesome Destin! :) I can't believe I just saw this now! Thanks for all you do! God Bless!

  • Jayz Rhoades
    Jayz Rhoades 1 month ago

    have you question this MEXICO IS CLOCK WISE so IS Supposedly clock wise!
    and supposedly equator is below mexico
    so supposedly mexico shoul be the northen and anti clock wise something is really wrong, and by logic maybe north america is as well clockwise so its southern hemisphere so that MEANS EQUATOR IS ABOVE NORTH AMERicA! And Eurpoe Is Anti clock Wise So that Means Is Above! North america! wtf!!!!!!! like The falt earth map of the onu is the true one! or wtf!!!

    see the videos live of thequator
    your welcome world lol!!

  • Sp0oks00
    Sp0oks00 1 month ago

    Another cool effect that you can see is that in Derek's video, he's having a little more trouble with the food coloring, as its sinking straight through to the bottom. This is a clear indicator that the water in Derek's video is warmer than the water in Destin's video.

  • Rodrigo Velásquez
    Rodrigo Velásquez 1 month ago

    You guys should both travel to Ecuador and set two pools , one just north of the equator and the other just south, and make the same experiment. And you could add a third pool, in the very equator. And see what happens too. It should be awesome to see them at the same time spinning in diferente directions. Regards....

  • Rodrigo Velásquez
    Rodrigo Velásquez 1 month ago

    Simplemente espectacular... que ingeniosa idea la de los 2 videos, felicitaciones

  • Christopher Smallwood

    i cant tell you how cool these videos were. well done. I loved it

  • Enes Jashari
    Enes Jashari 1 month ago

    what happens when the pool is in the equator

  • Brian Smith
    Brian Smith 1 month ago

    what happens with the swirl on the equator or poles?

  • Zephree Zen Gold
    Zephree Zen Gold 1 month ago

    my comment is on veritassium

  • Farinhir
    Farinhir 1 month ago

    Was already subscribed to you. Vertitasium got my subscription today. Like his name. Guessing it indicates something to do with truth.

    Ah, I see in the video. An element of truth. Glad i figured out at least some of it.

  • Ethan Patane
    Ethan Patane 1 month ago

    I experienced the change in flow rotation direction in real life. I went to the galapagos, but first stopped in Ecuador, where I went to the equator. The tour had a portable sink with him that had a removable plug in the bottom of it. He put the plug in, filled it up with water, and moved it perhaps a yard to the left of the equator. As the water drained, it spun clockwise. After it drained, he filled it back up and moved it one yard to the RIGHT of the equator. Sure enough, the water spun counterclockwise. But that's not the best part. He then filled it back up and drained it right on top of the equator. This time, when the water drained, it didn't spin AT ALL. It was really incredible!

  • ShadyNinjaGaming
    ShadyNinjaGaming 1 month ago

    brilliantly made
    Getting Smarter -(other vid)

  • Dafuq
    Dafuq 1 month ago

    i thougth the earth was flat

  • Hunter McFarland
    Hunter McFarland 1 month ago

    i live there

  • bernardakoito
    bernardakoito 1 month ago

    snipers knew about this for a long time

  • Koenshakuable
    Koenshakuable 1 month ago

    (cont'd from the other channel).. feeqin awesome!!!

  • Kwong Lung Ching
    Kwong Lung Ching 1 month ago

    Will you do the same experiment at the equator?

  • Emma
    Emma 1 month ago

    That was so cool!

    HOPEFOR TRUTH 1 month ago

    absolute nonsense the world is flat there is zero measurable curvature. vast bodies of water cannot conform to the outside of a shape in reality. water always finds level

  • Z_E_D
    Z_E_D 1 month ago

    Awsome Double video experience! The timing can't have been easy! =)
    Great job! and fun to learn

  • shaheen eagle
    shaheen eagle 1 month ago

    Well after watching like 20 videos you now have earned my subscription. congrats.👌👌👌👍👍👍

  • Max Davis
    Max Davis 1 month ago

    I kept watching both videos at the same time when the synchronization ended...

  • Muhammad Zaidan
    Muhammad Zaidan 1 month ago

    squatting toilet> sitting toilet

  • Jørund Eldøy
    Jørund Eldøy 1 month ago

    This explains stuff, not the swirling effect, but why the video was weird when i saw it two years ago.

  • Ananthan S Menon
    Ananthan S Menon 1 month ago

    the second half of

  • The Porcupine
    The Porcupine 1 month ago

    if I drain my bath tub and start turning the water the other way with my finger it always ends up gowing the right way in the end.

  • Cakeman
    Cakeman 1 month ago

    that was so cool when played side by side!

  • Ryo Ryo
    Ryo Ryo 1 month ago

    this video is creative...

  • Siberian Orange
    Siberian Orange 1 month ago

    Wow! The whole synced videos thing was amazing!!! Hope that idea catches on!! Great job guys!

  • Alexandra M. Firebaugh

    But why do the actual major ocean currents and hurricanes rotate clockwise in the northern hemisphere, and vice versa for the southern hemisphere?....

  • Sam Peterson
    Sam Peterson 1 month ago

    I love what you guy's did with this video!!!! So smart and awesome! I've been subscribed to both of your channels for some time now... glad to see two of my most entertaining choices working together.😁 thanks guys!

  • lol 231
    lol 231 1 month ago

    awesome video

  • mac steven de villa
    mac steven de villa 1 month ago

    what happens when a hurricane from the nothern hemisphere cross the equator?

  • Антон Леднёв

    You should make 100 attempts for clear experiment. ^_^

  • Ya Mi
    Ya Mi 1 month ago


  • Ran dom
    Ran dom 1 month ago

    Children in African could have drank that water.

  • spawnage17
    spawnage17 1 month ago

    200,000 more people have watched Destin's video than Derek's video. This means that 200,000 people had no idea what was going on.

    These two videos were so freaking cool.

  • CVE
    CVE 2 months ago

    its the constellation of heaven/clouds, moon and the sun rotation that's causing it not the earth rotating....

  • bubmah axr
    bubmah axr 2 months ago

    what is this science people were so pridefully competitive about...??

  • Anodos Arcade
    Anodos Arcade 2 months ago

    What happens if you drain it upside-down

  • Benjamin Hershey
    Benjamin Hershey 2 months ago

    Protip: put Destin on the left and Derek on the right for proper orientation.

  • ERA
    ERA 2 months ago

    its funny now people make big deals about small things like which way the water swirls xD Why does it matter which way it goes down? Just be gratefully that it actually goes down!

  • mian  fazle razik
    mian fazle razik 2 months ago

    I saw the video on both channels

  • Daniel Auen
    Daniel Auen 2 months ago

    How about perfectly on the equator?

  • Mr Delaney
    Mr Delaney 2 months ago

    Ecclesiastes 1:6 " The wind blows to the south and turns to the north; round and round it goes."

    I love that you put bible verses at the end of your video

  • Omid Ganjavi
    Omid Ganjavi 2 months ago

    The way he was sticking his face in the toilet was disturbing...,

  • Carmine Griego
    Carmine Griego 2 months ago

    notice he put the water in clock wise thats so it would go clock wise this whole water thing is just a wives tail its just a myth its fake

    • Carmine Griego
      Carmine Griego 20 days ago

      Kel Duck that is what they want you to think

    • Kel Duck
      Kel Duck 20 days ago

      He put the water in clockwise and then the water flowed anticlockwise down the drain.

    • Carmine Griego
      Carmine Griego 20 days ago

      Kel Duck what is your point?

    • Kel Duck
      Kel Duck 20 days ago

      Perhaps you should have watched the video

  • ToastyRoland
    ToastyRoland 2 months ago

    Sync these videos up.. it is extremely worth it. Cheers.

  • Cthulu Muramasa
    Cthulu Muramasa 2 months ago

    Haven't seen the vid but I know it's the coriolis effect

  • Michael Green
    Michael Green 2 months ago

    Like this so Smarterevry day to awnser this!!

    Whats the song that was playing durning to kitty pool?!

  • Everybody90
    Everybody90 2 months ago

    the other side

  • Snakezombie
    Snakezombie 2 months ago

    i told my friend on skype that lives in the northern hemesphere to screen share sync this up and it became wierd

  • RegularBrady
    RegularBrady 2 months ago

    Loved the syncing of the videos, super fun!!!

  • Rrroonald Weasly
    Rrroonald Weasly 2 months ago

    Perfect sync, first try. MVP.

  • instrumentalmane14
    instrumentalmane14 2 months ago

    Who else got dizzy at 4:33

  • Antony Theriault
    Antony Theriault 2 months ago

    Really cool videos guys, but geez do you not realize how hard it can be to sync two videos on the same computer?

  • Simon Ruszczak
    Simon Ruszczak 2 months ago

    Wrong, the direction depends on the drain.

    Dumbereveryday !

  • dilen noris
    dilen noris 2 months ago

    Fake news.

  • The all knowing sause
    The all knowing sause 2 months ago

    I am using my phone... can someone re upload this with it synchronized

  • Crazy Izzy
    Crazy Izzy 2 months ago

    So unfair I only have a phone to watch on

  • koplerio
    koplerio 2 months ago

    Sucks If I'm not able to make both go the same time. (southern Hemisphere)

  • Rohan N
    Rohan N 2 months ago

    hey wait what about the equator??

  • CRaSHeCLiPs
    CRaSHeCLiPs 2 months ago


  • Johannes Kunder
    Johannes Kunder 2 months ago

    The syncro was awsome!
    Pleasanton give us more!

  • Darth Chop
    Darth Chop 2 months ago

    YES! Thank you!

  • Mate Rodić
    Mate Rodić 2 months ago

    soo cool

  • mattp1482
    mattp1482 2 months ago

    I think you should go to the southern hemisphere and do it again.. that would be proof

  • Dartnix
    Dartnix 2 months ago

    One of the best ideas I've seen on youtube and very well put together!

  • Screaming Match
    Screaming Match 2 months ago

    Ya'll did great!

  • RCStormOrb
    RCStormOrb 2 months ago

    When you get the timing right first time and the videos in the right order ... YEAHAHAHAHAA

  • Dj2xP
    Dj2xP 2 months ago

    Hahaha, I have a dual screen setup so synching these was not hard, but I chose to put Veritasium's video on my left screen, which broke the immersion at the end :D

  • BarnabyFilibuster Jones

    This is one of the best uses I have ever had for my second monitor :)

  • anonymous bosh
    anonymous bosh 2 months ago

    This could be faked or it could be coincidence. Either way it's an utterly ridiculous way to try to prove something that is theoretically true but in practice has been shown at least twice by universities with far more resources and patience than you to be impossible to prove or disprove on anywhere close to such a tiny scale. Attempting to do so using loose plastic kiddies pools in any old room is not only laughable but now casts serious doubt on your ability to inform us of anything with any certainty at all. Well done.

  • Oscar Jeans
    Oscar Jeans 2 months ago

    waiittt.... how does video have 200,000 more views?? but 1000 less likes?...

  • Evan Tee
    Evan Tee 2 months ago

    Watched this with dual monitor one video on each. pretty cool idea

  • WheatWormStudios
    WheatWormStudios 2 months ago

    Too bad you made a video without doing any research. A toilet isn't big enough to be effected by by your made up effect and that has been documented. It has everything to do with the design of your toilet. Fail

  • Wynand Henderson
    Wynand Henderson 2 months ago

    Very cool experiment, but I would like you to at least test 3 times at the same place and replacing the nozzle at the bottom.

  • Bron Cinzah
    Bron Cinzah 2 months ago

    If you understand this video i think you

  • Seán Mercier
    Seán Mercier 3 months ago

    Hey guys, wanted to say I've been watching both of your channels for a while now and just stumbled across this. Being from a Video making background, I found this synchronised fusion really exciting on top of your usual high quality content. Thanks for doing what you do!

  • williamstdog9
    williamstdog9 3 months ago

    Awesome vid(s) bro(s)!

  • DR. NEO
    DR. NEO 3 months ago

    the sync was amazing

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