Does Water Swirl the Other Way in the Southern Hemisphere?

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3 år sedan

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:

BirdOPrey5 3 dagar sedan
But does it really prove anything if not repeated? Also... What happens then if the pool is perfectly on the equator? Is there no swirl?
Sebastian Balseca
Sebastian Balseca 8 dagar sedan
All you have to do, is visit the equator line in Ecuador. There, in a small museum called Inti Ñan, they take the same tub and demonstrate the different swirls just by crossing the equator by 1 meter. And the best part, right on the equator, there is no swirl.
Waheeb Abugharsa
Waheeb Abugharsa 10 dagar sedan
Good job 💚
Raulson Fontana
Raulson Fontana 18 dagar sedan
When the American uses meters and the Aussie uses feet 😢
Priyanshu Kumar
Priyanshu Kumar 20 dagar sedan
Hmm. What if the pool's at middle of equator? With half at N and half at S?
Jake Fiscus
Jake Fiscus Månad sedan
It does i tried it it will spin counter clockwise
Michael Lane
Michael Lane Månad sedan
You guys should replace high school science classes! So much better (and more correctly) explained than my teachers did.
Paul Månad sedan
I read some flat earthers saying the test needs to be done a hundred times. More iterations would be good, but it wouldn't matter to those cultists. Do it 100 times, and they will demand 101.
John barfneck
John barfneck Månad sedan
their theory is still not proved........its still a theory..............just like evolution vs God's creation. : )
John barfneck
John barfneck Månad sedan i can just picture each one of them trying to force the water to turn the other way like bart simpson their hero......
Ken James Jr
Ken James Jr Månad sedan
Right, because there is no Hemisphere on the earth... Just like the Coriolis Effect, any mainstream so-called proof of the ball-Earth is a lie and a deception.
Kel Duck
Kel Duck 25 dagar sedan
Why can't hurricanes cross the equator on a FE?
Rahul Dhargalkar
Rahul Dhargalkar Månad sedan
mateo branca
mateo branca Månad sedan
You should have tested adding water in the other direction just in case to make sure it just doesn't go backwards and they both went opposites
Hey blokes, rather than studying the rotation water swirls, how about swirling some soap on that toilet shown at the start of this video!
That's Write
That's Write Månad sedan
Wouldn't that mean doing the experiment on the equator the water would flow directly to the drain without any motion applied to it, or would it still flow clockwise or counter clockwise?
Ishan Pednekar
Ishan Pednekar Månad sedan
Sorry Hank
Tyr Odins
Tyr Odins 2 månader sedan
believe what these guys say. don't question anything. curses to remember: "flat earthers are stupid", "flat earthers deserve to die." Or you can hit a flat earther anytime you want.
Cory Roberson
Cory Roberson 2 månader sedan
How does this not shut flat earthers up???
Arnaldo Janiak, Jr
Arnaldo Janiak, Jr 2 månader sedan
No. Water swirls the other way in the northern hemisphere.
Giant Steps
Giant Steps 2 månader sedan
I was in Fiji and it was different..God is in control not man🙏🏼
Alabamian Mapping
Alabamian Mapping 2 månader sedan
Did you control for variables like they did?
Giant Steps
Giant Steps 2 månader sedan
What generation has overcome its own death and remains alive today?
Giant Steps
Giant Steps 2 månader sedan
Otherwise every man could overcome his own demise!
Alex Dobre
Alex Dobre 2 månader sedan
I knew it!!!
Shantanu Chakraborty
Shantanu Chakraborty 2 månader sedan
This is the best explanation..
Lilo Cahyo
Lilo Cahyo 2 månader sedan
here iam in the equator try zero latitude
Barry Larry
Barry Larry 2 månader sedan
Escape plan when Stallone guesses the geographic location
Mandorle21 2 månader sedan
Worst nightmare for flatearthers.
bbbbrianb 3 månader sedan
This is great except that the die goes in after you pull the plug....You can't see if the water was truly still before you pulled the plug!
Shikhar Gupta
Shikhar Gupta 3 månader sedan
Okay... While I believe that your theory has a good probability of being right. It doesn't say that such swirl should not happen even when the plug is not pulled. So ideally, when the water is left for a long time. Or an inert gas is kept in a container where the adhesive forces are nil, the fluid should flow in a circular motion and in the direction as predicted. But does it happen? Unless we know that I'll still be a little skeptical.
Kel Duck
Kel Duck 3 månader sedan
Are you ignoring there 7 results (0.5% chance of randomly occurring) and the thousands of times this has been completed under more stringent conditions.
Devaang Dev
Devaang Dev 3 månader sedan
Kimo sabe
Kimo sabe 3 månader sedan
Destin, question. May I assume that the blue marker is in the North-South orientation , outwards towards the North? Derek, Question, may I assume that the blue food coloring is in The South-North orientation with the South pointing towards the outwards? Appreciate an answer.
Hatboy 3 månader sedan
what if you go between them and do that?
Fern Bedek
Fern Bedek 3 månader sedan
Since ocean currents flip again closer to the poles, would the pool draining flip again too?
Alabamian Mapping
Alabamian Mapping 2 månader sedan
No, Ocean currents are because of the winds and the winds are.... a bit more complicated
coastermania17 3 månader sedan
I have a coworker who is convinced that this experiment is not repeatable and you got lucky because even though the water appears completely still, there are still other forces that could have caused it to go one way or the other, such as shear forces between the pool and the water, temperature gradients causing convection currents if the temperature is not uniform throughout from thermal cycling, inconsistent flows through the valve propagating back through the pipe, etc. and given the size of the pool, the difference in velocity is almost zero. Can you confirm or refute this claim. I personally think that it's legitimate, but at the same time, I can see where other factors that just can't be dampened out enough may play a role in which direction it spins.
Kel Duck
Kel Duck 3 månader sedan
They repeated the experiment 7 times, for the same result. So not repeatable and luck are not an issue. "For the record Destin and I repeated the experiment 3-4 times each in each hemisphere and got the same results every time."
Hiralis 3 månader sedan
This video is the easiest proof that the earth is round
SternLX 3 månader sedan
Besides Hurricanes and Cyclones also look at the Earths Ocean Currents and the circular motions in them in the North and South Hemispheres. Wind and Temps can only do so much, you need the Coriolis effect to get the Ocean Currents moving like they do.
Carlos Miguel Morais
Carlos Miguel Morais 3 månader sedan
Goodbye flatearthers
Wayne H
Wayne H 4 månader sedan
I live less then 10 miles from the equator in Africa and the water usually drains without any spin. Even toilets flush straight down in our house. I think that's why the drain is super large diameter pipe. To get a good flush without any swirl.
Frightening Genius
Frightening Genius 4 månader sedan
5 minutes 58 seconds of ignoring flat earthers exist
dr Manhattan
dr Manhattan 4 månader sedan
So much water wasted😔😢
Crazy Atom
Crazy Atom 4 månader sedan
Poor editors that had to deal with this one.
Aditya Sagar
Aditya Sagar 4 månader sedan
The music made it sound like they created coronavirus vaccine from a dead bat
Lzy Life Guide [SUBSCRIBE!]
Lzy Life Guide [SUBSCRIBE!] 4 månader sedan
I thought this was shown to be a myth previously... Now it's true?
Kel Duck
Kel Duck 3 månader sedan
Perhaps look at all the experiments that have been completed, or observe hurricanes/cyclones.
Dan Whitehurst
Dan Whitehurst 4 månader sedan
Sometimes my toilet doesn’t drain in any direction. I need to eat more fiber.
DeltroxTv 4 månader sedan
the videos of those people at the equator they make it go different directions based on how they fill it. These people are leeches and capitalizing on this effect by faking it to tourists.
Blacophis 4 månader sedan
Fun fact : Due to the coriolis effect, the hair on men's is swirled in different direction. You can look at their occiput and see the direction will vary depending on which hemisfere you are or on which hemisphere they've been living
J L 4 månader sedan
Coh! Vid.
night4life 4 månader sedan
i mean this is proof that a flat earth cannot exist, right? because if the earth was flat there would’nt be multiple/two hemispheres
Z Aliy
Z Aliy 4 månader sedan
Explain that flat earther!!
Benoît Lu
Benoît Lu 4 månader sedan
short answer: it's possible, but very unlikely to happen
Humam Hussain Shiyam
Humam Hussain Shiyam 4 månader sedan
Nice syncing
Alex Jansson
Alex Jansson 4 månader sedan
That was a great experiment!
NORMAN IVINS 4 månader sedan
how many times did you repeat the experiment! people have show it swirls both ways not matter where you are at! do better science!
NORMAN IVINS 4 månader sedan
@Kel Duck they did it together. again get it together before you respond. veritasium is the same issues - doesn't answer tough questions to his faulty paradigm
Kel Duck
Kel Duck 4 månader sedan
@NORMAN IVINS Your on the wrong site this is Veritasium's site.
NORMAN IVINS 4 månader sedan
@Kel Duck learn to read duck i never said you stated it was shown 7 times. if you would just take time to read. Just because they state it does not make it true. smarter everday is a nasa fan boy. that is why i told you to watch his video with astronaut don petit. He over looks a very important issue that could not possibly be true because he want to believe in all the space crap and outer space
Kel Duck
Kel Duck 4 månader sedan
@NORMAN IVINS Where did I state it was shown 7 times, keep to reality, please. Reread what Jay y wrote for the rest of my answer.
NORMAN IVINS 4 månader sedan
@Kel Duck you are the imbecile. they did not show it 7 time dumbass. you can say just about anything in the description. it would have been easy to show. they have been proven wrong about their conclusion by several people. he chose a sink because it could be transported easy.and it works just the same even better.
Smokey Saint
Smokey Saint 4 månader sedan
Flat earthers are gonna hate this one
BlackKnife 4 månader sedan
I don’t need sleep, I need ANSWERS
Emanuell Lux
Emanuell Lux 4 månader sedan
Well, I am sure bothered that with just two pools they say " we've proved the coriolis effect". One experiment does not constitute a reliable source to construct knowledge.
Alabamian Mapping
Alabamian Mapping 2 månader sedan
This is simplified, but they did repeat the experiment quite a bit
Jayy y
Jayy y 4 månader sedan
this video was an at home experiment done to be an example for middle schoolers.
Absent Rocket
Absent Rocket 4 månader sedan
Its already been proven multiple times tho this is just an educational video bruh
Mr Jake
Mr Jake 4 månader sedan
why did this sound like a motivational video?
cpobyrne1 4 månader sedan
n=2!! need more data to convince me!!
Alabamian Mapping
Alabamian Mapping 2 månader sedan
"For the record Destin and I repeated the experiment 3-4 times each in each hemisphere and got the same results every time."
Idae Chop
Idae Chop 4 månader sedan
The timing is sooo perfect
Robin Wallace
Robin Wallace 4 månader sedan
That's a very interesting video and one that has left a few questions in my mind. If the water were to emerge INTO the pool from the hole in the bottom, do you think it would begin to turn counterclockwise in one hemisphere and clockwise in the other? I'm asking because weather events are made up of either an ascending air mass or subsiding air mass. When the air mass is subsiding it moves along the surface towards the lower pressure area away from the center. When the air mass is ascending it moves along the surface towards the low pressure in the center. Therefore I'm wondering if the water were to move away from the center of the pool would it rotate the other way?
Josh2802 4 månader sedan
Bets that this is gonna be a new technique for geoguessr?
kilroy987 4 månader sedan
Nope, thanks.
Jerry G.
Jerry G. 4 månader sedan
Great description. Well done demonstration!
Fruit is Good
Fruit is Good 4 månader sedan
No it doesn't, it swirls the other way in the Northern Hemisphere
Manetinaj 4 månader sedan
Next video: we got to macapa in brasil to see what would the corriolis effect do at the equator
Tsksksktsk 4 månader sedan
4:06 if it was in in the south/north pole it would be frozer smh
Nhật Anh Bùi
Nhật Anh Bùi 4 månader sedan
4:10 I don't get it. You didn't do these experiment in the Sount pole or North Pole.
Barbriallen 4 månader sedan
Does Water Swirl the Other Way in the Southern Hemisphere? idk wat r u sayin, here spin the same ways as ever lel
Uncreeperble Gaming
Uncreeperble Gaming 4 månader sedan
But we are not perfectly on the bottom of the earth. We are on the side Edit: found my issue tysm
Alabamian Mapping
Alabamian Mapping 2 månader sedan
It still works because, unless you're on the equator, going closer to the equator means you're farther out in the circle
Artur Renato B.B
Artur Renato B.B 4 månader sedan
The effect is exactly the same, just not as drastic.
s8chi 4 månader sedan
Hurricanes/tornadoes: cmon its 2020 why dont you use me as a test Like rlly its *2020* how bad can it get
Al Amin Ananda
Al Amin Ananda 4 månader sedan
But what would happen if a tornado was to travel from the northern hemisphere to the southern hemisphere or vice versa ?
Jayy y
Jayy y 4 månader sedan
the effect is insanely small, it would create a small source of friction but wouldnt have drastic affects like youd expect.
Artur Renato B.B
Artur Renato B.B 4 månader sedan
It would lose energy and dissipate.
Wolf Is Bad
Wolf Is Bad 4 månader sedan
but can you do it 50 times and get 100% same result ?
Alabamian Mapping
Alabamian Mapping 2 månader sedan
They did it about 7 times and got the same result (99.2% certainty) roughly 3 sigma. Not quite high enough, but there are also more advanced scientific papers on it if you look.
Jayy y
Jayy y 4 månader sedan
this is a vid intended to show lil kids how to create the effect. Theres been thousands of labs of it.
MadPotty01 4 månader sedan
... but how do the flat earthers explain it?
Abdulrahman Alotaibi
Abdulrahman Alotaibi 4 månader sedan
Did you account for a possibility of the valve opening influencing a swirl and that the direction of rotation might change with change of valve orientation?
Moonlit Snowstorm
Moonlit Snowstorm 4 månader sedan
If the valve effected rotation, then the results would be different due to the differences of valve used between them. One had a stopper, which shouldnt realistically cause any turbulence when popped, and the other had a turn-valve, which **also shouldnt cause any change in turbulance**
bratkartoffeln123456 4 månader sedan
first world problems
Phil Chia
Phil Chia 4 månader sedan
A scientist, and an engineer, both describing the same thing differently with different words. It is a beautiful thing. Education is what lets you get that. Learn the words people, so you don't become internet stupid.
Yan Wong
Yan Wong 4 månader sedan
I can imagine the neighbours looking out their windows to find a grown man screaming out science stuff beside a colourful kiddie pool.
Harry Ferrett
Harry Ferrett 4 månader sedan
I wanna see a flat earther explain that
davide khalil
davide khalil 5 månader sedan
but... to telephone cords wind the other direction as well?
Sam Grainger
Sam Grainger 5 månader sedan
Love the n number of 2
Mark C
Mark C 5 månader sedan
That why us left handers are called Southpaws because when we stir things , drinks etc it`s clockwise . Admit it you all mimed it
Brett_Kendrick 5 månader sedan
If they were both draining the same way it would mean that the hemispheres were rotating opposite each other around a single axis.
Alabamian Mapping
Alabamian Mapping 2 månader sedan
Well not quite. Earth rotates from west to east. from the north pole, that's counterclockwise, but at the south pole, the same direction is clockwise. It is kinda confusing though.
AS921 5 månader sedan
I wonder why this video comes up when you search for "toilet spin" meme.
Shreyank R
Shreyank R 5 månader sedan
It is not true, it is a myth, the swirl is due to the shape (geometry) of the pool. Please check the exact result of coriolis effect of the earth. Thanks everyone.
Alabamian Mapping
Alabamian Mapping 2 månader sedan
If it were due to the shape of the pool, then they would spin the same way because they are the same pool.
林 勇
林 勇 4 månader sedan
The pool is identical
Brian 5 månader sedan
Or look at it another way....high pressure weather systems turn anti clockwise in the southern hemisphere and low systems turn is the opposite direction for both in the northern hemisphere
INST_32_Wong Shean Nyean
INST_32_Wong Shean Nyean 5 månader sedan
Damn... both of my favorite SVfromr in one video this is so damn good.....y'all should club together was an amazing video....
H B 6 månader sedan
Coriolis Force does potentially cause water to swirl in opposite directions in the Northern and Southern Hemisphere, but there is no way you could prove this during such a poorly controlled simple test as the influence is so tiny under such a small scale. Can you make sure there is abosolutely no movement and the surface is flat in the first place? Unless you can show a water drain without any swirlling on the equator, you cannot prove the validity of this test.
Alabamian Mapping
Alabamian Mapping 5 månader sedan
they tried it multiple times and got the same result
wierdawgg 6 månader sedan
I just want to know why it looks like my toilet water moves when it's just sit for a long time.
ANGRY MILK 6 månader sedan
So the water just fall in the equator?
Suleman Shamshuddin
Suleman Shamshuddin 6 månader sedan
very bad demonstration very bad.
violetcrumble94 6 månader sedan
So it's real, just doesnt happen.. Odd
Enrique Hernaiz
Enrique Hernaiz 4 månader sedan
It does happen, it is just that on small scales the effect is almost negligible compared to other sources of disruption for the water
Chris Lynn
Chris Lynn 6 månader sedan
seriously, you 2 only pulled the plug ONCE and that's that!? at least do more than one trial, how do you call that an experiment?
Alabamian Mapping
Alabamian Mapping 2 månader sedan
To quote the description: "For the record Destin and I repeated the experiment 3-4 times each in each hemisphere and got the same results every time."
Kel Duck
Kel Duck 6 månader sedan
read the description above.
Rachel Rachel
Rachel Rachel 6 månader sedan
how does water swirl at the equator, like the city of Banjarmasin in Indonesia?
penguin82875 6 månader sedan
Flat earthers be crying right now
EL YHWH YETI 7 månader sedan
I need to clarify this, bc of this water swirl experiment the results shld prove the Earth is spinning??
Pluto pluto
Pluto pluto 7 månader sedan
Thats not how the earth rotates, u turned it upside down🤣🤣 it rotates on its axis..
CS IHDA 7 månader sedan
Checkmate, Globetard!
林 勇
林 勇 4 månader sedan
I think this is against you
Alabamian Mapping
Alabamian Mapping 5 månader sedan
that's... actually a checkmate for flattards
dchall8 7 månader sedan
We had a 25-ft water tank at my college to demonstrate this effect.
papajahatcom 7 månader sedan
thanks you
sushankgiri minecraft
sushankgiri minecraft 7 månader sedan
Just go to Uganda or equador
Jasdeep Bindra
Jasdeep Bindra 7 månader sedan
Lol... You can never exclude all the variables. Besides there is also the orientation of the drain plug you used. I still think it's too small to decide Coriolis effect. Maybe repeat the experiment a few more times with different drain plugs
TURKOMANIAC V2.0 7 månader sedan
nonsense ! The coriolis force is to weak to proove it in that way. It affect Macro Objects like wind etc. It would explained in a ideal world, but the world or environment circumstances aren't ideal. So its depend on the initial factors like surface, angle and disturbances.
Kel Duck
Kel Duck 4 månader sedan
@TURKOMANIAC V2.0 With regards to the tides: The Moon orbits the Earth once every approx. 28 days while the Earth rotates once per day. The water bulge (high tide) isn't moving as you think, the Earth is doing most of the moving. The Earth's rotation gives us our 3 to 4 tides per day. If the Earth wasn't rotating, there would only be 4 tides every 28 days.
TURKOMANIAC V2.0 4 månader sedan
@Kel Duck It's true. But a self-experiment in a pool is much too little to experience the Coriolis force. Of course, they do have an minimal effect, but the effect of the initial Begin, surface conditions and other forces around the pool are many times greater, so that the Coriolis force only plays a minor role in which direction the water vortex is created. In general, vortex currents are one of the most complex physical processes that exist.
Kel Duck
Kel Duck 4 månader sedan
@TURKOMANIAC V2.0 Correct water is just a molecule, nothing special. The sea and oceans are just a massive congregations of single water molecules, that are just experiencing similar forces. That is the reason why there are tides, they are free to move where the forces take them.
TURKOMANIAC V2.0 4 månader sedan
@林 勇 Contrary to the assumption of many people, bathtub vortices do not always turn in the same direction on one hemisphere. Rather, it is a matter of chance whether the water flows off clockwise or counter-clockwise. The reason for this is the size of the vortices: they are much too small to be influenced by the rotation of the earth.
TURKOMANIAC V2.0 4 månader sedan
@Kel Duck Yes, but there is no single particle buzzing around, but a huge heap of particles that make a difference in terms of mass. What do you think that the sea moves at high and low tide? According to your logic, these are also single water molecules.
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