Does Water Swirl the Other Way in the Southern Hemisphere?

  • Published on Mar 20, 2017
  • The definitive answer about the direction water swirls in two hemispheres
    Sync the videos yourself:
    For the record Destin and I repeated the experiment 3-4 times each in each hemisphere and got the same results every time.
    The idea that water going down a drain or flushed down a toilet swirls in opposite directions in the Northern and Southern Hemispheres has a long history. But few have ever done the experiment. Destin from Smarter Every Day and I performed identical experiments in the Northern and Southern hemispheres. What we found is the direction of water swirl in a toilet, sink, or bathtub is determined by other sources of angular momentum. However if the body of water is big enough, e.g. a kiddy pool, and left still for long enough (at least 24 hours), then the Coriolis effect is observable with water swirling counterclockwise in the Northern hemisphere and clockwise in the Southern hemisphere.
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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:
  • Runtime: 5:59
  • veritasium  science  physics  smarter every day  water  swirl  toilet  flush  coriolis effect  swirls  drain  way  direction  destin  derek  hemisphere  northern  southern  spins  vortex  experiment  pool  angular momentum  clockwise  counter-clockwise  flow  Earth  

Comments: 2 308

  • Seth Goodnight
    Seth Goodnight 9 hours ago

    holy cow, please look up planetary vorticity and delete this video.

  • Karl Fernandez-Cao
    Karl Fernandez-Cao 5 days ago

    If you live on the equator the water doesn't drain. It just stays there.

  • swagalina
    swagalina 5 days ago

    wow what a great video

  • C-zar
    C-zar 8 days ago

    So, the water is affected by the spin of the earth but we don't. That makes perfect sense.

    • Kel Duck
      Kel Duck 8 days ago

      If you were formed with just individual water molecules, of course you would be effected.

  • Marshall Curtis
    Marshall Curtis 10 days ago

    Fascinating video! I liked, subbed, and belled.

  • dieter heinrich
    dieter heinrich 16 days ago

    It will swirl any way u force it to turn, no mater where u are.

    • Kel Duck
      Kel Duck 8 days ago

      Correct, Which proves the coriolis effect is very tiny.

  • The Loph
    The Loph 16 days ago +1

    461 flat earthers has watched this to this date

  • maxi soulcaliber
    maxi soulcaliber 16 days ago

    Earth's rotation? Nope. Stationary. More globe indoctrination.

    • Kel Duck
      Kel Duck 8 days ago

      So what made the water spin?

  • angthuonimo
    angthuonimo 23 days ago

    That's a fake. The food colouring in the water clearly shows laminar flow around the edges, esp at 3:30 on the left. That means the water was already rotating. You're also showing an effect many orders stronger than the real coriolis effect.

    • Kel Duck
      Kel Duck 16 days ago

      They just left the pool/water alone and let the coriolis effect continually act on the small pool of water to cause the rotation.

    • angthuonimo
      angthuonimo 21 day ago

      I know THEY didn't say that water has to move toward the hole to be affected by the C.E., but I already know that. I don't know how it got to be circulating that way round - I wasn't there to watch when the camera wasn't rolling.

    • Kel Duck
      Kel Duck 22 days ago

      Perhaps watch the video again, not really anything about water having to move to be effected. They also fill the pool against the rotation that coriolis will impart.

    • angthuonimo
      angthuonimo 23 days ago

      Read what I said more closely. I know friction stops stuff moving, but there should be no coriolis effect anywhere near the wall cos that water hasn't moved. Unfortunately there's rotation about six inches from the wall. The C effect affects things WHEN THEY MOVE, but the water at that position hasn't moved. That motion must be a pre-existing current.

    • Kel Duck
      Kel Duck 23 days ago

      Yes there is no movement of water at the zone where friction is a greater force, this is due to friction being larger than the coriolis force. It doesn't mean the coriolis effect has been magically removed, its still there, just too small to overcome the friction.

  • Genzo
    Genzo Month ago

    though my toilet NEVER rotates and it dosnt go down like this so rip

  • Carlos Moran
    Carlos Moran Month ago

    Aparte esta el efecto Coriolis en el agua

  • Hamish Whibley
    Hamish Whibley Month ago

    What would happen, if the cyclone/hurricane started in one hemisphere, but then went to the other? Would it change direction, or just keep going the way it already is...

  • ________ _______
    ________ _______ Month ago

    Stupid lisa

  • Tri Le
    Tri Le Month ago

    the shape of the drain hole/pipe could influence it. they dont show what is under the pool. and he should repeat it several times to make sure it doesnt spin the otherway next time,
    and take the same pool to the other hemisphere and show it spins in the other direction.
    just search Michelson-Morley ,Michelson-Gale experiment, (professor Michelson is 1907 Nobel prize winner) Airey's failure, Sagnac experiment , Pier Luigi Ighina la terra ferma experiment,
    proving earth isnt moving.
    In 1986 The US Air Force repeated the Michelson-Morley experiment, published in the Nature Journal Volume 322. reproving the motionless earth.

  • Weeaboo
    Weeaboo Month ago

    who else watched the actual video after trying to sync it yourselves to see how bad they did?

  • eric Wilhelm
    eric Wilhelm Month ago

    What are the other reasons for angular momentum that totally wash out that effect in your opinion ?

  • Ryan Brewster
    Ryan Brewster Month ago

    would a drain directly on the equator not spin at all?

  • Jarek Rodriguez
    Jarek Rodriguez Month ago

    I think the next question is; Which direction will water swirl with a drain centered on the equator?

  • SGT Norgan
    SGT Norgan Month ago

    And water on the equator flows straight down

  • SilverDax
    SilverDax Month ago

    As someone living in America, seeing a cyclone going clockwise looks kind of weird.

  • Gaming With Porpoise

    What if ur on the equator what is the outcome?

  • Mark Wright
    Mark Wright Month ago

    So if you stand on the north pole water should not rotate at all and instead go directly down.

  • Tri Le
    Tri Le Month ago +1

    take the same pool to the other hemisphere to prove it spins in the other direction
    nice try.

    • Tri Le
      Tri Le Month ago

      here neil degrasse tyson explains gravity , he also claims earth is pear shaped.
      so where are the peer reviewed scientific experiments proving earth is moving? you fall for these spinning toilets and pools story?

  • Kyle Rnm
    Kyle Rnm Month ago

    Does this also happen in the equator

    • Kel Duck
      Kel Duck Month ago

      No coriolis effect on the equator

  • semperfi 1918
    semperfi 1918 2 months ago

    so the die in one pool didn't go anywhere... yup there's proof. btw isn't there 4 jet dreams not 2 lol makes a lot of sense to me yeah if you are exactly polar opposite but your not either. and this still doesn't prove jack. try doing the experiment 100 times.

    • Kel Duck
      Kel Duck Month ago

      You made no sense with your comment.
      You may have had 4 jet dreams though

  • Megamarioman #1
    Megamarioman #1 2 months ago


  • gotohell gotohell
    gotohell gotohell 2 months ago

    Hu ..take that doubters .
    Good vid ..

  • Chris A
    Chris A 3 months ago

    Science, testable… observable… repeatable… You guys did one test?
    Try pouring the dye in 15 minutes before pulling the plug Or leave the little ducky in the water To prove no movement of the water. Come on guys

    • Kel Duck
      Kel Duck 2 months ago +1

      Perhaps read the description

  • Chris A
    Chris A 3 months ago

    How many times was the test repeated?

  • miran Kim
    miran Kim 3 months ago

    the most understandable experiment ive ever seen in utube!

  • aluisious
    aluisious 3 months ago

    Terrible test. Random chance would give you this result 1/4 of the time.

    • Kel Duck
      Kel Duck 3 months ago

      try hitting "show more"

    • aluisious
      aluisious 3 months ago

      It doesn't display the 3rd line by default, douche.

    • Kel Duck
      Kel Duck 3 months ago

      Fair enough, It was too hard to read up to the 3rd line in the description.
      Good luck.

    • aluisious
      aluisious 3 months ago

      This isn't the Library of Congress. It's a short-format video content site. Anyone who expects that people are going to find a small link that says "show more" and do a bunch of reading is going to be sorely disappointed by life generally.
      It's poor editing.

    • Kel Duck
      Kel Duck 3 months ago

      They didn't gain all of the knowledge that was available, before they commented.

  • X X
    X X 3 months ago

    I'v noticed that the person in Alabama 'should' be using feet/inches, yet his pool was "1.5 meters."
    Derek, meanwhile, was in Australia, where the metric system is the standard. And his pool is "5 feet."

  • The Chloe
    The Chloe 3 months ago

    Wow.... This is so cool!!! I always questioned this!!!!!!

  • Andre V.C.
    Andre V.C. 3 months ago +1

    some equatorian tour guide guy has a video showing that just above the line it spins one way and just bellow the opposite. and hes done it a bazillion times. that settled it for me.
    nice video btw. but as someone already commented it need more repetition to be science - but that would be a waste of water!

  • colin-man yeates-clan
    colin-man yeates-clan 3 months ago

    Well thanks for the share.. great stuff... I wrote this on another blog site but was unable to publish it so I'm dumping this off here for more study and comments.:
    Wow, my father was a physicist and I remember something about the ??? effect and that it spins one way in the nort.. bla bla.. But I think I have discovered the truth of the matter, now that I know it is open.
    My observations over a long time and many long showers with all sorts of settings of the shower, my body and even guiding the water to flow a certain way.
    Now I was raised on a sailboat sailing as a 6yo a 24ton dry and about 43 tons wet 56ft Cutter 68ft double diamond rig mast and a 7.5 ft draft. It has been around the world twice before we lived aboard for close to 6 years both Atlantic and Pacific and north and south of the equator... (and for shits sake I went through the now outlawed initiation on an aircraft carrier at sea to become a "Trusty Shellback") at any rate... gee should I somehow evidence other than this that I may actually have "discovered" revealed to me the true answer?..
    So I'm in the shower yet again and recalling how certain other times I have seen the water persistently went one way and other times the other... testing each condition out with my hand held showerhead with various streams, can direct in numerous ways front side and even backwards on the centerline of the tub to see uninfluenced stream at least from the start... to thoroughly verify the effect or lack thereof. So, this morning at 5am in Maryland(outside DC) and this time it is going counterclockwise... so I do my experiments and indeed it favors the counterclockwise direction, even after forcing it to go clockwise it would require constant coercion to keep it going else it would spin the counterclockwise direction.
    Now being raised on a sailboat I'm more aware of the sun, pressure, moisture, smell etc... i've been called the weatherman because I am able to fairly predict the weather.. kinda helps when you windsurf in storms... So I am a bit more aware of various "spheres of influence" such as the sun, moon, tilt of the axis, magnetic fields, sun bursts, pollen, pollution, temperature etc... So from being on a sailboat I tend to know "instinctively" which way is North... so drum roll please.. at 5am in the summer time (the ark of the Sun is high and wide)and from the east... sun rises in the east... but it sets in the west.. so have you got it yet? the pull of the sun in the early am in summer time when it will be almost directly overhead meaning that it will be due east and due west, it flows one way at sun rise and another at sunset due to the pull of the sun.. So I tested it our tonight and yup clockwise.
    If you take into consideration that most tests are done in the daytime probably in the afternoon to evening hours it invariably spun in that direction, but few are up at 4am when it is pulling from another direction.. So I will continue to verify and my suspicion is that it will dissipate as the winter approaches and the sun is consistently in a smaller arch and thus the pull relative to the tub will be constant no matter what time of day or night.
    So this makes sense too.. my problem with the ??? Effect of the spin of the earth is like arguing that if you toss a ball in the air it will land in a different spot and always in the direction of rotation or if you are on a train going 100 mph verses 500 mph the effect will increase in the direction of the train...
    BUT if you account for the pull of the sun on everything acting like a constant drag since clearly the earth is not spinning or not spinning in relation to the sun so that eventually the water and all atmosphere will bulge towards the sun and stay that way, but instead is always trying to fall to the sun pulling on it so that pull would equally try to accelerate the other half of the time except the tilt of the axis causes a pull to the south and pull to the north creating a wave like activity so you have a constant wave generator... Oh and let's not forget the influence of the Moon in all this... so next experiment is to see what the results are as the moon and the sun align and oppose. Appose causes high tides because water is a liquid but when they align it causes riptides because huge amounts of gravity is exerted on only one side of the earth at one time so everything is rushing to get there, but again cannot ever catch up.
    WoW how amazing perfect clockwork there is to cause all the effect to create this incredible paradise... What if we already are here but the evil has told a lie and made "Heaven" a place to get to, so that the effect is that we are not there....Here... I say we are already here, we just need to manifest a better one for ourselves and others by command (ask and believe) not order but command with full authority, just as we have over our creations but have lost our knowledge for prosperity by believing the lie of lacking. Abundance is Abundant! and all created and given to us... the most amazing gift ever... thank you Creator!!!!
    So in closing .. thank you all for participating and sharing without getting nasty... well most of you.. it is wonderful to hear others thoughts on various phenomena.. such as ourselves. Seriously have you ever conceived of the most contradictory creature? We are inherently social creatures and yet those who have the least amount of social interaction exhibit the most rejectionable attitude and antisocial behavior. Scientists claim is to discover what already is in the endeavor to explain it better and yet once they think they have figured it out nothing else will do. Religionists who believe in "God Almighty" belittle "God" into a box of their making and say God can not use "evolution" in creating and maintaining the universe for us and at the same time will want to stone you if you believe "God" grants you miracles on a daily bases...and scientists who admit that miracles do exist refuse to put it into their calculations... flat earther's continue to ass-ert the earth is flat when they have no real evidence of it ignore the most obvious evidence that it is not and the anti flat earther's refuse to believe there is or has been a giant conspiracy.... etc etc..
    Wow talk about diversity.. that is one thing we can all agree on.. Creator loves Diversity above all... Hello...

  • Sherrilee Carter
    Sherrilee Carter 3 months ago

    Excellent to see the two side by side!

  • Kiky
    Kiky 3 months ago +1

    i hate to say this but, how do flat earthers explain this?

  • Joel Marcy
    Joel Marcy 4 months ago

    I've got one for you all. If the spin has is in fact due to the equator, and the amount of pull based on how far or close you are to it, and you did one just by the equator, and one, say in Canada, than one should spin fast and hard, and the other slowly and lightly. Right? Anyone ever seen this tried?

  • Trevor Houser
    Trevor Houser 4 months ago

    would it spin on the equator

  • Shaswat Gupta
    Shaswat Gupta 4 months ago

    will definitely spend more time in the toilet 😉

    ANJOOM THAHIR 4 months ago

    Would this effect be visible in such a small scale ( hurricanes and cyclones are huge) ?

    • Kel Duck
      Kel Duck 3 months ago

      Assuming you watched the video. Yes, it is a visible effect over small scales.

  • Chelsee T
    Chelsee T 4 months ago

    All right so what about a pool perfectly at the equator?

  • Jonathan Nadeau
    Jonathan Nadeau 4 months ago

    What happen on the equator (perfect equator)?

  • Nicolás Urquía
    Nicolás Urquía 4 months ago

    What if you're on the Equator? or right in one of the poles? Which would the effects be?

  • iTwez
    iTwez 4 months ago

    my toilet dosn't swirl, water is instantly pushed down from the front and back

  • QED
    QED 4 months ago

    Well at least Destin believes in a round Earth, but it's no coincidence he's done a number of videos on creatures and never once mentioned evolution. I wonder why...

  • chilisos93
    chilisos93 4 months ago

    And what happens right on the Equator?

  • Michael8 schumi
    Michael8 schumi 5 months ago

    wax on wax off

  • Destroyers 101
    Destroyers 101 5 months ago

    Then what will happen in the equator

  • UnBearablePun CSGO
    UnBearablePun CSGO 5 months ago +1

    What if you're exactly on the equator

  • Mister Dinner
    Mister Dinner 5 months ago

    Before I watch this, my theory is that since the equator spins the fastest relative to the north and south latitudes, water will swirl in patterns reminiscent of a boat traveling through water. Each side gets pushed in a different direction and with the amount of water present in the oceans, the speed of the equator relative to north and south latitudes is enough to make water swirl in opposing directions on each hemisphere.

  • Southern Hemisphere
    Southern Hemisphere 5 months ago +1

    Hello mates, I came here to learn about myself :V

  • Jonathan Perez
    Jonathan Perez 5 months ago

    What happens at the equator?

  • Wes Netmo
    Wes Netmo 5 months ago

    is ewan mcgregor among the "other group of people"?

  • BeingJasonChong
    BeingJasonChong 5 months ago

    This is as concise as it can to describe the Coriolis effect direction of water swirls - but how does this effect the major ocean currents?
    Most text books on this subject states that the major ocean currents in the northern hemisphere (between America and Europe) are clockwise and in the southern hemisphere (between Australia and South America) are anti-clockwise - the exact opposite of the swirls as demonstrated in this video. Can someone explain?

  • Ranoiaetep
    Ranoiaetep 5 months ago

    Not sure if anyone else asked this question in the comments, but I'm wondering what would happen if the pool is placed right on top of the equator? Would it make a shape that is similar to an opposite "ɛ"?

  • CriticalMass
    CriticalMass 5 months ago

    Flat earth FATALITY

  • Miguel Zuñiga
    Miguel Zuñiga 5 months ago

    What if you're at the equator? Like exactly in the middle...

  • Lajos Winkler
    Lajos Winkler 5 months ago

    Yes, American toilets which waste a lot of water do give you an opportunity to show you this. Normal toilets have little water inside and use jet from a high placed tank to flush the waste.
    Also, you'd have to do this with a lot larger tanks in a sealed environment where there's no wind, and you'd have to do it lots of times for a statistics approach. This way, it's not scientific at all.

    • Kel Duck
      Kel Duck 5 months ago

      Its a demonstration of a phenomenon, the science was done elsewhere.

  • G3ØRGE
    G3ØRGE 5 months ago

    Do it on the Ecuator!!!

  • Burnt Gerbil
    Burnt Gerbil 5 months ago +6

    It's all a matter of perspective. One spins one way, the other spins opposite. Or does it?? Technically, they are spinning the same way relative to each other.
    Make a fist with your right hand, with your pointer finger, and point to the floor. Spin it to the right and you have clockwise. Now carefully turn your hand over so it points to the ceiling, and keep spinning. Is it going anti-clockwise? Turn it over again. Now it's clockwise, yet it's still spinning the same direction.....

    • Kel Duck
      Kel Duck 5 months ago +1

      Correct, our perspective changes depending which hemisphere you do the demonstration.

  • SeanDaRyan
    SeanDaRyan 6 months ago

    but the earth is flat!!!!

  • Fubukiyo
    Fubukiyo 6 months ago

    So, what happens at the exact middle of the equator?! I MUST KNOW.

  • Creeperbrine007
    Creeperbrine007 6 months ago

    This video sounds a little bit distorted to me. I'm not a big fan of scishow and Hank, but the coriolis effect and the toilets' flush doesn't have that much relation. It's true that coriolis effect does affect the water bodies when it comes to hurricanes or cyclones, or a big stable perfect cylinder-shaped tube. However, in normal toilets that the average human being use isn't so large and "flat" and stable. Coriolis effect is so small. The earth rotates per day, but the water that swirl in the normal toilets spin much, much faster than that. The Coriolis force does impact the direction of the flow of water, but only minutely. Only if the water is so still that the effective rotation rate of the Earth is faster than that of the water relative to its container, and if externally applied torques (such as might be caused by flow over an uneven bottom surface) are small enough, the Coriolis effect may indeed determine the direction of the vortex, like in this video. However, this is not the myth tells. The common myth insists that the water flow from a flushing toilet swirl depending on the very hemisphere we're at. There's nothing wrong about the experiment, but there is some misinterpretation which you made about the myth and what Scishow said. P.S. No Offence.

    • Creeperbrine007
      Creeperbrine007 6 months ago

      and the viewers need to listen to the video . Literally Listen please. they said in the video that the other variables can adjust the outcome!!!

  • FraznoFire
    FraznoFire 6 months ago

    But Australia doesn't exist..

  • Martim
    Martim 6 months ago

    awesome video

  • Jose Chavez
    Jose Chavez 6 months ago

    I saw a video where it was on the equator and the water went straight down

  • theodoros tsilikis
    theodoros tsilikis 6 months ago

    so if black holes are the hole and water is the galaxy what hehispere are they in?

  • Krishna Kumar
    Krishna Kumar 6 months ago

    this explanation is truly the best, hats off to you guys.

  • Al Couz
    Al Couz 6 months ago

    What happens at the ecuador ? The water wouldn't turn ? (sorry for my english i'm french)

    GGGPPPOOO Empty 6 months ago

    Used this as my science project sorry, copied some ideas...

  • Ciley Myrus
    Ciley Myrus 6 months ago

    but.. what about the ECUATOR?

  • James Bouwan
    James Bouwan 6 months ago

    D'you called this science?

  • intiferino
    intiferino 6 months ago

    How does water rotate on the equator then?

  • CarthagoMike
    CarthagoMike 6 months ago

    did they just succesfully correct SciShow?

  • milesteghades
    milesteghades 6 months ago

    I like this channel, but sorry to say this experiment is crap and it's not even close to the scientific method or proof of anything..
    You haven't eliminated all the variables , the design of the drain, or other imperfections could determine the way the vortex forms and you had a sample of 1 in each hemisphere.
    The amount of likes you got for this failure just shows how people still don't understand basic scientific principles including apparently the protagonists of the 2 channels i am subscribed to..
    I love both your channels and i learned a lot from them, but this is not how you prove something.

    • Kel Duck
      Kel Duck 6 months ago +1

      We it is just a scientific demonstration.
      You also should read the description before commenting.

  • Sashik Pro
    Sashik Pro 6 months ago

    for Samsung s8+ it will be a full screen video

  • Plant Head
    Plant Head 6 months ago

    It's not science to run one test and come to a conclusion. Thats not how science works.

    • Kel Duck
      Kel Duck 6 months ago +1

      Correct, but read the description next time.

  • Retro Player
    Retro Player 6 months ago

    What about on the equator?

  • Bob3D2000
    Bob3D2000 6 months ago

    No, you haven't eliminated all the variables:.
    Variables not eliminated:
    1. Overall geometry of the pools. These are flexible, plastic pools and their shapes could be different enough to affect the vortex direction.
    2. Macroscopic and microscopic surface variations. These can accumulate to give rise to a surprisingly strong effect. See chaos theory.
    3. Perturbations due to airflow across the surface. Self-explanatory.
    4. Perturbations due to vibrations from the floor (from for example, passing cars, etc.). This can combine with 1 and 2 to enhance the difference caused by those.

    • Kel Duck
      Kel Duck 6 months ago

      Cool, bye

    • Bob3D2000
      Bob3D2000 6 months ago

      1. So you really are suggesting that the shape of a container has no influence on the way a fluid flows through it! I was being sarcastic but you actually do? Bloody hell. You think these cheap, foldable, plastic pools are perfectly circular? Really? I know water swirls in a square sink; what's that got to do with it?
      I never said anything about friction adding velocity, you'd just made that up. You asked what mechanism could exert an unequal force and so I described the forces imparted on the water. Friction is a force.
      3. I never said it was a competition. How can the experiment be a fair test if in one location the pool is sheltered from outside winds and in the other it's exposed to them? A given location tends to have a prevailing wind (which is why all the trees on my street lean in the same direction). Hence, this variable isn't eliminated.
      4. A vibrator that moves up and down will move along just as well. Have you never used a plate compactor? It's nothing to do with a spinning motor. And why couldn't it be the same vibration over three days?
      None of this is complicated. You're replies are riddled with strawman arguments.  I don't know if you're being obtuse deliberately, but one way or the other, I'm done explaining these simple concepts; I have better things to do with my time.

    • Kel Duck
      Kel Duck 6 months ago

      1/ Both of the pools are circular and they were placed on flat and level surfaces. There is no difference in the shape of the pools. You do see vortices in a square kitchen sink.
      Friction would only slow the circular motion, it cannot add velocity as the pool is static with relation to the ground.
      3/ But the pool outside and the pool inside gave the same but opposite results. Why is it unfair, it wasn't a competition, just 2 scientific demonstrations.
      4/ A mobile phone has an asymmetric wheel spinning at a high velocity, this can impart a direction. Perhaps a vibration could effect the demonstration, but it would have to be the same vibration over 3 days.
      This is really a scientific demonstration of a known effect, they reduced as many variables as possible. Yes it wouldn't stand up to scientific scrutiny (ie sample size too small) but that has all been done previously under far more exacting standards.

    • Bob3D2000
      Bob3D2000 6 months ago

      1. The weight of the water is the force that causes it to flow into the hole. The water is therefore flowing over the plastic surface of the pool. If the pool's surface is uneven this could easily direct the vortex in one direction or another. The forces exerted by the pool are friction and the normal force to the water pressure. Are you suggesting that the shape of a container has no effect on the way water flows through it?
      2. Possibly, but not definitely and so this variable has nonetheless not been eliminated and the experimenters have not provided a discourse as to why the effects are negligible.
      3. One location was inside and the other was outside. Hardly fair. Did they move the pools to different locations?
      4. Have you ever seen your mobile move across the table when it vibrates? It doesn't take much if there's already some other offset (which is what I meant by enhancing 1 and 2). If, say, there's a wrinkle in part of the pool that makes that bit stiffer, such that an applied vibration causes that part to oscillate with a lower amplitude than another part, this could conceivably cause an imbalance in the way the water flows across these two parts of the pool.
      The point is this: whilst it may be true that the coriolis effect is indeed significantly more powerful than the combined effects of the variables I have described, this is not proven by the experiment. These variables may have been discounted - and if so the onus is on the experimenters to explain why - but they haven't been eliminated as there is nothing in the experimental design that does so.
      As an aside, note that the result found has a 1.6% probability of arising randomly.

    • Kel Duck
      Kel Duck 6 months ago

      1/ What is the mechanism, for the pool walls, to exert an unequal force into the water?
      2/they should cancel themselves out, after all it is chaos and there are a lot of water molecules in the pool.
      3/ Airflow is a possible variable, but considering they did the demonstration 3 times each over days that should be covered.
      4/I cant see how vibrations from the ground would cause a spin.

  • Chipp O
    Chipp O 6 months ago

    omg TANKS i needed this is school

  • MuhdZikry
    MuhdZikry 6 months ago

    man I like this!

  • life-of-sci
    life-of-sci 6 months ago +1

    I was at the equator in Africa and they did a demonstration where they put water in a funnel with a narrow opening, they blocked the opening with their finger - placed a wooden match stick on top of the water then let the water drain from the funnel. When they were on the North side of the equator the match rotated one way (counter clockwise) and when they stepped about 1-2 feet on the other side of the equator the match rotated the other way (clockwise). They did it again while straddling the equator and the match stick did not rotate at all. Amazing!
    That demonstration was amazing to me not only because of the rotation but because the actual equator is so narrow!

  • Ender586
    Ender586 6 months ago

    I am not convinced. If I had to guess, this was all just a coincidence. No matter how many times you try, if you are using the same-shaped pool (in a room with the same air flow, vibrations etc), it may always produce vortex of the same direction and still be completely unrelated to the Coriolis effect.

  • Rod Fell
    Rod Fell 6 months ago

    This experiment seems fairly sloppy and I wouldn't consider its results to be definitive.

    • Rod Fell
      Rod Fell 6 months ago

      The Coriolis effect is a well known phenomenon. That it can be demonstrated like this is not well known.
      The people who state that the coriolis effect is too small to be demonstrated like this say the swirl is caused the design of the basin/bath/tank. Just stating as fact that different pools can't affect the water direction is begging the question.
      I said Derek's experiment was sloppy and not definitive. I wasn't saying that the experiment hasn't been done elsewhere. I wasn't saying that the results were wrong.

    • Kel Duck
      Kel Duck 6 months ago +1

      So now you have 3 different experiments, at 3 different spots on the Earth, including MIT, all confirming the coriollis effect. If you searched you could find other places were this experiment has been attempted.
      This video is just a scientific demonstration of a well known phenomenon.
      Different pools cant effect the water direction, they haven't got a mechanism to add velocity to the water. The only thing the pool walls/construction could possibly do would be reduce the water spin by slowing the water velocity, which would make detecting motion harder.

    • Rod Fell
      Rod Fell 6 months ago

      They say they repeated the experiment 3-4 times. My assumption is they just emptied the exact same pools 3-4 times, so it's no surprise they got the same result. You can see they used a different pool in each hemisphere. If it was a properly constructed tank (as it was when MIT showed a counter-clockwise swirl in Boston), and the same tank was used in both hemispheres, and then the experiment was repeated using different tanks, the results would be definitive. Using two different kiddy pools was sloppy.

    • Kel Duck
      Kel Duck 6 months ago +1

      So your assumption is that, this is the first and only time this experiment has been conducted?

  • That One Weirdo
    That One Weirdo 6 months ago

    I would like to point out that, when a toilet flushes, it spews e-coli into the air. That is why I close the lid when done.

  • shimmer
    shimmer 6 months ago

    is this a re-upload??

  • Kevin Velez De Villa Mejia

    Noooooo!!!!! It's boring like this, it's alot alot alot more fun to get 2 phones or tablets and making it yourself lol 😂

  • De'Ja Nickle
    De'Ja Nickle 7 months ago

    Thx for syncing videos

  • Landon Lovette
    Landon Lovette 7 months ago

    Glad they showed the clip from Long Way Down where they did it on either side of the equator

  • Yashas
    Yashas 7 months ago

    What if a hurricane moves from the southern hemisphere to the northern hemisphere?

    • NocturnalDanger
      NocturnalDanger 7 months ago

      It is impossible to have a hurricane on the equator because there is no Coriolis effect, as you near the equator, the coriolis effect nears 0, so Id assume the hurricane would dissipate.

  • Herbert Ramirez
    Herbert Ramirez 7 months ago


  • 1chumley1
    1chumley1 7 months ago

    I wanted to see a nut-filled turd in one of those toilets.

  • Cameron Sipka
    Cameron Sipka 7 months ago

    this is amazing <3

  • po k
    po k 7 months ago

    Only one pool in each hemisphere doesn't prove anything. Thought I was on science channel :p

    • Kel Duck
      Kel Duck 7 months ago +1

      Perhaps you could build the 3rd pool and prove it to yourself.
      Or look up this experiment which has been done many times for the same results in many different places on the Earth.

  • Michael Covington
    Michael Covington 7 months ago

    Piss green from the sci show can suck it

  • MDFlight
    MDFlight 7 months ago

    and they only needed to try this 10 times to get their desired outcome, pretty good tbh

  • Jacob chamberlain
    Jacob chamberlain 7 months ago

    What about at the equator?

  • Ryu Vincent
    Ryu Vincent 7 months ago

    this video could probably be the most beautiful video on YouTube just because of how entertaining 2 guys try to explain simple science (rocket science being the not simple one)

  • Geklmin
    Geklmin 7 months ago

    recycled footage much?