The Truth About Toilet Swirl - Southern Hemisphere

  • Опубликовано:  2 года назад
    Both videos on one page (for desktop):
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    Some notes:
    We each repeated the experiment 3 times, and got the same results every time. For those of you who might be skeptical, great! A right circular prismatic kiddie pool is only $10 and you can do the experiment for yourself at your latitude. There's really no reason you shouldn't 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 Vanessa for filming in Sydney:


    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:
  • ОбразованиеОбразование
  • Длительность: 8:03
  • veritasium  science  physics  toilet  swirl  water  drain  northern hemisphere  southern hemisphere  coriolis effect  

Комментарии: 5 956

  • Andrey Nazarchuk
    Andrey Nazarchuk 2 дня назад

    What happens if you put it in the middle of antacrctica

  • Andre Feliciano
    Andre Feliciano 4 дня назад

    AWESOME Video collaboration is soo dope

  • Harman House
    Harman House 5 дней назад

    I think the uneven opening acts like a propeller. It should be perfectly round and flat.

  • Argha Nandan
    Argha Nandan 5 дней назад

    I had to continue this one at countdown 4... and after a sec, the other one at countdown 3.
    We need science to even synchronize these two videos!
    Hell yeah! SCIENCE!

  • Ross Marsden
    Ross Marsden 6 дней назад

    Brilliant demonstration about conservation of angular momentum and the (apparent) Coriolis Force. The main reason that Coriolis is not observed in basins and toilet pans is that they are dimensionally small, and as is often demonstrated, any residual circulation indicated in the body of water dominates. The reason you both got a positive result for Coriolis - cyclonic circulation (clockwise in the Southern Hemisphere and counter-clockwise in the Northern Hemisphere) is because of the SIZE (2 metres across) of your kiddie pools.

  • swarnadipmitra
    swarnadipmitra 6 дней назад

    Next time, I want a collab between Micheal from VSauce, Derek from Veritasium, Dustin from SmarterEveryDay and Henry from MinutePhysics because Windows 10 allows four tabs on the same screen. Can it be done?

  • Eli S
    Eli S 8 дней назад

    The sync thing is so cool.

  • NeenanTheNinja
    NeenanTheNinja 9 дней назад

    ...Double monitors are awesome

  • mafarnz
    mafarnz 9 дней назад

    Really cool guys, this collaboration was a lot of fun to watch!

  • Therealrobokaos
    Therealrobokaos 11 дней назад

    Since I had a video on each of my screens, when you guys switched at the end it just made you walk across my screens

  • Frankie Prokop
    Frankie Prokop 15 дней назад

    I also got to see stillness on the Equator.

  • Frankie Prokop
    Frankie Prokop 15 дней назад

    I was actually in Ecuador over the summer and went to the equator and got to see different swirls on either side of the equator.!

  • Manish Savkare
    Manish Savkare 20 дней назад

    how about doing this with three monitors... Veritasium - Vsauce - SmarterEveryDay

  • Aussie Soarer
    Aussie Soarer 22 дня назад +1

    7:20 made me realize I am wasting my life watching youtube videos.

  • Jacopo Paravano
    Jacopo Paravano 23 дня назад

    If the sink has a big hole for draining the rotatio will always be the same

  • Cold Death By Multiverses
    Cold Death By Multiverses 23 дня назад

    Wow, you just disproved the flat Earth theory!

  • ano nymus
    ano nymus 23 дня назад


  • alexandros domprojohn
    alexandros domprojohn 24 дня назад

    R.I.P Phone Users

  • Clickpn
    Clickpn 24 дня назад

    i just wanna say that i NAILED the sync. NO LAG

  • Loren Ransom
    Loren Ransom 28 дней назад

    This collaboration was so impressive!

  • Univentures UT
    Univentures UT 28 дней назад


  • Univentures UT
    Univentures UT 28 дней назад


  • Jackie Shi Gaming
    Jackie Shi Gaming 29 дней назад

    so, what will happen if you drain the pool at the equator?

  • Alexandria R. Triplett
    Alexandria R. Triplett 29 дней назад

    Destin from SmarterEveryDay sent me here and I must say bravo guys! This is an awesome collab I feel smarter already!

  • millertas
    millertas Месяц назад

    The Southern Hemisphere is the best. It is on the side pointing towards the middle of the galaxy. Far more stars (including the milky way) are visible AND Christmas in summer with it still light well into the evening) especially here in Tasmania.

  • Freddie Vandyck
    Freddie Vandyck Месяц назад


  • Jacob Brink
    Jacob Brink Месяц назад

    So what happens when you drain a pool on the equator? Nothing?

  • H2TA
    H2TA Месяц назад

    looks good with dual monitors

  • shutemdwn
    shutemdwn Месяц назад

    That was cool how you synced the videos. Do some more of that!

  • justin hyland
    justin hyland Месяц назад

    This is an amazing video! good idea on the synchronous videos as well.
    Ive knew about the Coriolis effect, but this experiment is an awesome illustration.

  • Joseen Garcia
    Joseen Garcia Месяц назад

    It was way too much for my mind to process.

  • Achmad Syauqi
    Achmad Syauqi Месяц назад

    never been this so damn serious watching my toilet water swirling

  • Sarah Treadwell
    Sarah Treadwell Месяц назад

    that was soooo good!

  • xXE4GLEyEXx
    xXE4GLEyEXx Месяц назад

    This is...

  • roslan mat ali
    roslan mat ali Месяц назад

    this right

  • B Rice
    B Rice Месяц назад

    Cool idea, guys!

  • Dr.Evil/// Shadow hunter
    Dr.Evil/// Shadow hunter Месяц назад

    what was with the faces

  • ZEM pro.
    ZEM pro. Месяц назад

    this was a really cool idea! its awesome how you guys managed to synchronize the videos perfectly!

  • Tiphanie Morgan
    Tiphanie Morgan Месяц назад

    The rotation of the water is based upon the direction from which you drained the pool. Since you were to right of the pool this caused the spin to have a clockwise rotation to the right. Just as the guy in the northern hemisphere in Alabama drained the pool from the left side of the pool causing a counter-clockwise rotation. The Coriolis Effect is as real as Gravity.

  • Jeff Forsythe
    Jeff Forsythe Месяц назад

    Awesome videos thanks

  • Eldar Djedovic
    Eldar Djedovic Месяц назад

    What if you do it on the equator

  • Charlie Flor
    Charlie Flor Месяц назад

  • Ilay Morlevi
    Ilay Morlevi Месяц назад

    Damn! how did you manage to do that?!

  • lou crecc
    lou crecc Месяц назад

    Shill Nye shill

  • lou crecc
    lou crecc Месяц назад

    33 degrees of south latitude Freemasonry..

  • Reid Jameson potts
    Reid Jameson potts Месяц назад

    Would the spin or drain be faster according to disctance from each pole???

  • Zain Abdeen
    Zain Abdeen Месяц назад

    How about at the equator??

  • Richard Waskiewicz
    Richard Waskiewicz Месяц назад

    That was awesome! :D :D

  • jason of the disbury family
    jason of the disbury family Месяц назад

    Dont listen its fake the conditions are not the same the Container has to be the same and the plug hole has to be the same the water has to be put in the same the conditions were not the same FAKE FAKE

  • Amber Ridgdill
    Amber Ridgdill Месяц назад

    So then what happens directly on the equator?

  • The Big Pickles
    The Big Pickles Месяц назад

    Awesome vids. well done

  • Nithar Shana
    Nithar Shana 2 месяца назад


  • KitKatinBama
    KitKatinBama 2 месяца назад

    That was amazing!!

  • Noel Ruppenthal
    Noel Ruppenthal 2 месяца назад

    This format not exactly compatible with a veritasium marathon late at night with an iPad

  • Can Attal
    Can Attal 2 месяца назад

    You were dropping dye in it and you claim the water to be still. You people are desperate.

  • Chris Modisette
    Chris Modisette 2 месяца назад

    Fantastic work!

  • Aryamaan Singh
    Aryamaan Singh 2 месяца назад +1

    ...and put this video on right. You are welcome :)

  • Armin Hierstetter
    Armin Hierstetter 2 месяца назад

    Awesome job, guys!

    PS: This comment is synced.

  • Geert Vis
    Geert Vis 2 месяца назад

    What will the water do on the exact middle of the earth, the Equator?
    The middle of north and south?

  • OG Afghan
    OG Afghan 2 месяца назад

    Try it in Saudi Arabia in Mecca please...

  • TieXiongJi
    TieXiongJi 2 месяца назад

    Great pair of videos. This helped me win an internet debate, but it was already obvious thanks to the hurricanes I have seen on the Weather channel.

  • winko567
    winko567 2 месяца назад

    i wonder how it would flow if u were right on the equator

  • miamicanez16
    miamicanez16 2 месяца назад

    You skewed the results adding the drops and bumping the table as you did it.

  • miamicanez16
    miamicanez16 2 месяца назад

    I clearly seen you bump the table a few times and cause ripples. If you were a real scientist you would do this multiple times and see if it is REPEATABLE. Im not convinced the wind or something else couldn't play a factor.

  • HackiH
    HackiH 3 месяца назад

    So which of the 2 videos is actually more successful? Veritasium has (today) about 8.9% less views but its like to dislike ratio is 80.6 compared to 76.4 and it even has 2.25% more likes :D I guess the most important question is why the heck did i calculate that?

  • Lamar Shealey
    Lamar Shealey 3 месяца назад

    you have to do this it is cool

  • John Larrabee
    John Larrabee 3 месяца назад

    super cool videos

  • Daniel George
    Daniel George 3 месяца назад

    Wow that was just amazing :)

  • Tim Evanchick
    Tim Evanchick 3 месяца назад

    That was super awesome!

  • pecfree
    pecfree 3 месяца назад

    time to bed now flatards

  • William McCormick
    William McCormick 3 месяца назад

    There is another possible explanation. The axis of the planet is charged from the North Pole to the South Pole, by the movement of the planet in the atmosphere and the atmosphere and its contact with the light gases of space.

    This actual electrical effect might be the actual effect that causes the water to spin in one direction as opposed to the other. It at least posses variables that must be answered before you call this done or explained.

    At the North Pole the Aurora Borealis is not electricity created by the earths spinning, rather it is a reactionary electricity created to and against the electricity that is drawn into the North Pole by the earths spinning. Much like lightning is the reaction to electricity from the earth, striking the cloud face of a storm cloud that cannot pass that quantity of electricity through the cloud and into the vastness of space.

    If your hypothesis about the pool spinning because one side of the pool is moving faster than the other is correct, then you would have to prove that without interaction of any kind that the pool constantly swirls without draining of any kind. In the direction you predict it will spin. This may be true or not, I do not know. However it would be so if your theory is correct.

    I believe that when the water starts moving, vertically, it creates a magnetic field in order to do so. I believe it is this magnetic field that causes the direction of the swirl, along with the different electrical fields of the earth in the North and South hemisphere.

    The actual magnetic interaction of the North and South hemisphere seems rather a complex situation to explain. I am sure it could be explained. But I think it would take a few years and a lot of serious research to do so, before it did not seem like blatant conjecture even if totally accurate.


    William McCormick

    • William McCormick
      William McCormick 3 месяца назад

      I think a magnet kind of demonstrates a little bit of the principle I am trying to put across.

      Basically the way a magnet can attract steel at both the North and South Pole of the magnet, yet repel similar poles of another magnet.

      The center of the magnet between the North and South pole of the magnet becomes neutral while both ends have a similar effect on steel.

      It could be that both the North and South pole create a similar effect on water and the equator another. That could explain why a vertical flow could cause the two different effects on the North and South Hemisphere respectfully.


      William McCormick

  • Chad Kennow
    Chad Kennow 3 месяца назад

    This was awesome Derek! :) Keep up the great work! :)

  • Rodrigo Velásquez
    Rodrigo Velásquez 3 месяца назад

    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 3 месяца назад

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

  • Christopher Smallwood
    Christopher Smallwood 3 месяца назад

    you have my subscription. awesome videos you did with Destin. well done.

  • tinkmarshino
    tinkmarshino 3 месяца назад

    you guys are crazy fun!

  • Melvin Duckenfield
    Melvin Duckenfield 4 месяца назад

    At 4:08 he states, "So really you're not gonna see it in a bathtub and you're not gonna see it in a sink or in a toilet because there are other sources of angular momentum that totally wash out this effect." What are those sources? It appears to me that there are multiple variables to be considered before one can definitively "prove" the desired conclusion. Additionally, only one experiment was done. Can we draw a definitive conclusion based on one experiment? Could the direction of the air current above the pool, since it was outside, have affected the direction in which the water drained? Were both platforms identical and completely level? I would be more inclined to consider his conclusions if he and his partner had repeated their experiments multiple times under various conditions and in various locations in the respective hemispheres to prove their hypotheses. Isn't that what the scientific method is all about?

    • Kel Duck
      Kel Duck 3 месяца назад

      A demonstration of a scientific experiment, is just that, a demonstration.

    • Melvin Duckenfield
      Melvin Duckenfield 3 месяца назад

      My understanding of the scientific method is that more than two or three experiments under extremely controlled conditions do not provide sufficient, empirical evidence for a theory to be considered a fact. In the age of "consensus science" I suppose conducting an experiment a statistically irrelevant amount of times will just have to suffice.

    • Kel Duck
      Kel Duck 4 месяца назад

      If you read the description, it does tell you how many times it was completed. (3)

      You probably should also realise this is a scientific demonstration, they don't need to do it a statistically relevant amount of times.

      This experiment has been done many times in many different parts of the world, the hypothesis has already been proven in more exacting circumstances.

  • Cody Deforest
    Cody Deforest 4 месяца назад

    That was cool guys

  • Zephree Zen Gold
    Zephree Zen Gold 4 месяца назад

    great team work see my comment on smarter everyday

  • mike nguyen
    mike nguyen 4 месяца назад

    the screen warp was pretty sick

  • DMatthewHenry
    DMatthewHenry 4 месяца назад

    This was really freaking cool.

  • ShadyNinjaGaming
    ShadyNinjaGaming 4 месяца назад

    Brilliantly made
    (other vid) - every day

  • jakub Kraus
    jakub Kraus 4 месяца назад

    Too bad the Earth is obviously flat...


  • Koenshakuable
    Koenshakuable 4 месяца назад

    that was... (on the other channel)

    HOPEFOR TRUTH 4 месяца назад

    what a load of nonsense

  • Z_E_D
    Z_E_D 4 месяца назад

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

  • Xero
    Xero 4 месяца назад

    cringy end

  • HYDRO4123 Gaming
    HYDRO4123 Gaming 4 месяца назад

    this is to much effort to know which way a toilet flushes

  • Robert crowdiver Burns
    Robert crowdiver Burns 4 месяца назад

    horseshit,, it does the same up north !

  • Ananthan S Menon
    Ananthan S Menon 4 месяца назад

    this comment is here.
    find it

  • Ryo Ryo
    Ryo Ryo 4 месяца назад

    this video is creative...

  • Sam Peterson
    Sam Peterson 4 месяца назад

    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!

  • Felix P.
    Felix P. 4 месяца назад

    awesome video

  • Ya Mi
    Ya Mi 4 месяца назад


  • Sean Freeman
    Sean Freeman 4 месяца назад

    that was dope af

  • bubmah axr
    bubmah axr 4 месяца назад

    i watched both videos chronologically on a single screen, one video after the other, so the real drain happens on my brain.

  • Benjamin Hershey
    Benjamin Hershey 5 месяцев назад

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

  • Connieisland0
    Connieisland0 5 месяцев назад +1

    This is video is so misleading and untrue. It throws the scientific method out the window.
    Water spins according to the shape of the drain, its immediate surrounding. Sadly the masses will be believe a video like this more than making the experiment themselves.
    If people think that earth rotation is detectable by no other instruments but a simple water flow going down a drain, then they should really do a check up with the reality around them.
    There are no instruments that ever detected the rotation of the earth, however you're telling us that water going in a drain gets affected by this so called rotation??

    • sedawk
      sedawk 4 месяца назад

      "There are no instruments that ever detected the rotation of the earth" - Wow. Just Wow. Perhaps you should take your foot out of your mouth and google Foucault's Pendulum.

      Their experiment is valid. You can completely predict and calculate the force that caused the rotation. The predicted force is small - hence the caution in the experiment. True - you don't see this everyday because most other forces overcome the forces imparted on the water due to the Earth's spin - but this was clearly stated and demonstrated in the video as well.

  • Сергей
    Сергей 5 месяцев назад

    In my bath it always swirls in one direction. Even if i try to change the swirling direction with a stick or smth like that, water changes the direction again to the initial one after a minute or so.