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:
  • КатегорииОбразование
  • Длительность: 8:3
  • Тэги для этого Видео:  veritasium  science  physics  toilet  swirl  water  drain  northern hemisphere  southern hemisphere  coriolis effect  

Комментарии: 5 904

  • Nithar Shana
    Nithar Shana 5 дней назад


  • KitKatinBama
    KitKatinBama 5 дней назад

    That was amazing!!

  • Noel Ruppenthal
    Noel Ruppenthal 8 дней назад

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

  • Can Attal
    Can Attal 9 дней назад

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

  • Chris Modisette
    Chris Modisette 11 дней назад

    Fantastic work!

  • Aryamaan Singh
    Aryamaan Singh 11 дней назад

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

  • Armin Hierstetter
    Armin Hierstetter 13 дней назад

    Awesome job, guys!

    PS: This comment is synced.

  • Geert Vis
    Geert Vis 17 дней 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 19 дней назад

    Try it in Saudi Arabia in Mecca please...

  • TieXiongJi
    TieXiongJi 20 дней 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 23 дня назад

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

  • miamicanez16
    miamicanez16 28 дней назад

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

  • miamicanez16
    miamicanez16 28 дней 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 1 месяц 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 1 месяц назад

    you have to do this it is cool

  • John Larrabee
    John Larrabee 1 месяц назад

    super cool videos

  • Daniel George
    Daniel George 1 месяц назад

    Wow that was just amazing :)

  • Tim Evanchick
    Tim Evanchick 1 месяц назад

    That was super awesome!

  • pecfree
    pecfree 1 месяц назад

    time to bed now flatards

  • William McCormick
    William McCormick 1 месяц 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 1 месяц 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 2 месяца назад

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

  • Rodrigo Velásquez
    Rodrigo Velásquez 2 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 2 месяца назад

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

  • Christopher Smallwood
    Christopher Smallwood 2 месяца назад

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

  • tinkmarshino
    tinkmarshino 2 месяца назад

    you guys are crazy fun!

  • Melvin Duckenfield
    Melvin Duckenfield 2 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 1 месяц назад

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

    • Melvin Duckenfield
      Melvin Duckenfield 1 месяц 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 2 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 2 месяца назад

    That was cool guys

  • Zephree Zen Gold
    Zephree Zen Gold 2 месяца назад

    great team work see my comment on smarter everyday

  • mike nguyen
    mike nguyen 2 месяца назад

    the screen warp was pretty sick

  • DMatthewHenry
    DMatthewHenry 2 месяца назад

    This was really freaking cool.

  • ShadyNinjaGaming
    ShadyNinjaGaming 2 месяца назад

    Brilliantly made
    (other vid) - every day

  • jakub Kraus
    jakub Kraus 2 месяца назад

    Too bad the Earth is obviously flat...


  • Koenshakuable
    Koenshakuable 2 месяца назад

    that was... (on the other channel)

    HOPEFOR TRUTH 2 месяца назад

    what a load of nonsense

  • Z_E_D
    Z_E_D 2 месяца назад

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

  • Xero
    Xero 2 месяца назад

    cringy end

  • daniel hoad
    daniel hoad 2 месяца назад

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

  • Robert crowdiver Burns
    Robert crowdiver Burns 2 месяца назад

    horseshit,, it does the same up north !

  • Ananthan S Menon
    Ananthan S Menon 2 месяца назад

    this comment is here.
    find it

  • Ryo Ryo
    Ryo Ryo 2 месяца назад

    this video is creative...

  • Sam Peterson
    Sam Peterson 2 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!

  • lol 231
    lol 231 2 месяца назад

    awesome video

  • Ya Mi
    Ya Mi 2 месяца назад


  • Sean Freeman
    Sean Freeman 2 месяца назад

    that was dope af

  • bubmah axr
    bubmah axr 2 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 3 месяца назад

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

  • Connieisland0
    Connieisland0 3 месяца назад

    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 2 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 3 месяца 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.

  • ToastyRoland
    ToastyRoland 3 месяца назад

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

  • Cthulu Muramasa
    Cthulu Muramasa 3 месяца назад

    Just learned this in science

  • Cthulu Muramasa
    Cthulu Muramasa 3 месяца назад


  • Cthulu Muramasa
    Cthulu Muramasa 3 месяца назад

    It's the Coriolanus effect

  • bleuthoot
    bleuthoot 3 месяца назад

    This is the ultimate way to collaborate

  • Everybody90
    Everybody90 3 месяца назад

    hello from

  • Sirake
    Sirake 3 месяца назад

    Damn, I'm already subscribed to both :(

  • D-Schloss the boss H-town rowlin hard
    D-Schloss the boss H-town rowlin hard 3 месяца назад

    how did you know i put you on the right

  • RegularBrady
    RegularBrady 3 месяца назад

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

  • Rrroonald Weasly
    Rrroonald Weasly 3 месяца назад

    Perfect sync, first try. MVP.

  • Antony Theriault
    Antony Theriault 3 месяца назад

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

  • koplerio
    koplerio 3 месяца назад

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

  • CRaSHeCLiPs
    CRaSHeCLiPs 3 месяца назад


  • Mate Rodić
    Mate Rodić 3 месяца назад

    soo cool

  • Dartnix
    Dartnix 3 месяца назад

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

  • Screaming Match
    Screaming Match 3 месяца назад

    Ya'll did great!

  • Dj2xP
    Dj2xP 3 месяца назад

    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

  • Ali Tahrei Sh.
    Ali Tahrei Sh. 3 месяца назад

    What about equator?

  • qwchrbichn
    qwchrbichn 3 месяца назад

    The truth about toilet swirl is that toilets force the water in one direction or another. The side-by-side sink comparison is hardly surprising. A better side-by-side comparison would be ones with drains in the center of each compartment.

  • BarnabyFilibuster Jones
    BarnabyFilibuster Jones 3 месяца назад

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

  • Liza Marie Rios
    Liza Marie Rios 3 месяца назад

    omg you guys are awesome.

  • Bron Cinzah
    Bron Cinzah 3 месяца назад

    're amazing ...if you follow this you're Genius...

  • FuckYouGooglePlus
    FuckYouGooglePlus 3 месяца назад

    This is jus silly. A 12 foot pool is NOT showing off the Coriolis effect. The effect on something that small would be way more than canceled out by imperfections in the pool itself. Like not being level, or any deviations from roundness, etc. Even imperceptible wind.

  • silikonmanufaktur
    silikonmanufaktur 3 месяца назад

    Wow, didn't think it would really work ! Amazing. Did you try several times to make sure it wasn't just a lucky coincidence ? Best way to do it would be using several pools at the same time, to make sure no tiny asymmetry in the outlet, the valve, the plug etc determines the direction of the rotation. Because that might easily be the case, considering the incredible tiny difference in angular momentum we are talking about. And air has a lot less friction compared to water, while the distances covered by those storms are hundreds of miles ! I must confess i would have bet money on you guys failing to show the coriolis effect in a kiddie pool ! Congrats and well done ! :-)

  • Tej Pal Singh
    Tej Pal Singh 3 месяца назад

    all my favourite people in one video.

  • jon pounders
    jon pounders 3 месяца назад

    why didn't you guys do the same test in the northern hemisphere to make this study complete?

  • Seán Mercier
    Seán Mercier 3 месяца назад

    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!

  • DR. NEO
    DR. NEO 4 месяца назад

    the sync was amazing

  • Vincent Paul
    Vincent Paul 4 месяца назад

    I synchronized the video and it was very interesting.

  • Brian Killough
    Brian Killough 4 месяца назад

    could we place something low that would hardly if not at all be affected by wind to flow to a specific spot in the ocean? Is the pool and the hole in perfect symmetry and perfectly level?

  • Death_Kenny
    Death_Kenny 4 месяца назад

    Got it timed perfectly first try... Really amazing Idea of you both! Loved it!

  • Maven Sony
    Maven Sony 4 месяца назад

    Now do this experiment in exactly midpoint of equator .Lets see what happens..

  • znatim
    znatim 4 месяца назад

    You could mention Foucault experiment

  • sharan kaur
    sharan kaur 4 месяца назад

    Happiness when u r subscriber of both channels 😆

  • kuonirat
    kuonirat 4 месяца назад

    Now I can impress my female colleague, who claimed otherwise.

  • Southern Hemisphere
    Southern Hemisphere 4 месяца назад

    Name stealer :(

  • Strike Eagle
    Strike Eagle 4 месяца назад

    Im subbed to him but i still dont know what i am doing with my life

  • Strike Eagle
    Strike Eagle 4 месяца назад

    That... Was... AWSOME! The 2 vid idea was crazy cool!

  • MrG
    MrG 4 месяца назад

    what a great idea! You both are awsome guys. I allways said the internet is a huge dunghill where here and there thrives a flower. You are these flowers I was seeking. Stay smart and above all, stay curious.

  • zazke girotron
    zazke girotron 4 месяца назад

    hey this is cheating: 2 views at the same time per person... well played

  • oceanceaser
    oceanceaser 4 месяца назад

    This is AWESOME

  • Dean Stewart
    Dean Stewart 4 месяца назад

    Champion effort guys

  • mrcleanisin
    mrcleanisin 4 месяца назад

    I haven't read all the comments, but surely someone asked them why they didn't repeat the expirments more than one time?

    • Kel Duck
      Kel Duck 2 месяца назад

      Perhaps read the description instead

  • zoomiie
    zoomiie 4 месяца назад


  • Mohamad Zaid
    Mohamad Zaid 4 месяца назад

    nice..i did sync both video with two monitor. haha burnn

    ANDROID GAMING 4 месяца назад


  • Al-mujahedeen Salahadeen
    Al-mujahedeen Salahadeen 4 месяца назад

    SmarterEveryDay brought me here!

  • MWB Gaming
    MWB Gaming 4 месяца назад

    1:32 you are not here in AU
    our power outlets look like an arrow not like the face of someone getting probed

  • dan hewitt
    dan hewitt 4 месяца назад

    Who else subbed from smarter every day? Great channel btw? I like ur vids alot. 😊 peace from the UK

  • farooq shaik
    farooq shaik 4 месяца назад

    Open Two tabs and cascade

  • Geeky Tech
    Geeky Tech 4 месяца назад

    what will hAppen if you. we're on the. equator