How to Make Low Pressures with a Capillary tube

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In this video I show you how capillaries can decrease the pressure in a liquid well below an absolute vacuum if they are small enough
Veritasium Video on Trees: • How Trees Bend the Law...
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14 окт 2024

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Комментарии : 517

@destroyishere4655 4 года назад

I have a feeling that he's slowly revealing his superpowers...

@glaizasulim3611 3 года назад

yes

@TheRealGuywithoutaMustache 4 года назад

If I were to be serious for once, I just wanted to say that your video ideas are always creative and fascinating.

@EPBP 4 года назад

Why are you here

@Longshin777 4 года назад

oh it's you

@vinaythakur4742 4 года назад

Mumbo is also is missing his Original moustache

@CyanDumBell_MC 4 года назад

where's your brother

@الاسلامرمزالسلام 3 года назад

👋👋👋👋👋

@germenfer 4 года назад

I must say that lower pressure sucks.

@thejoker7902 4 года назад

I am a strong man. but that thing ( *James's un-even mustache* ) it scares me.

@MedEighty 4 года назад

Okay, so I'm not the only one who noticed that.

@error-dc2ox 4 года назад

Hey! He can’t go to the barbers okay

@xZangHD 4 года назад

My handle bars screamed when I saw that

@TheBaseCam 4 года назад

Because it's not a moustache, it's what's controlling the main body you know as 'James'

@pratikdas8328 4 года назад

well, the meniscus are formed due to the adhesion forces and the surfacw tension of the liquid, which it was mentioned in the later part but when the meniscus was mentioned first time( in case of the capillary tube), it is not due to the pressure difference but due to same reasons stated above that's why water will always form a conclave meniscus with glass containers irrespective of any pressure difference

@AmandeepSingh-qe4ok 4 года назад

exactly what I'm thinking

@chanakyasinha8046 4 года назад

And mercury forms convex

@sheetalagarwalla1241 Год назад

But again the minscus has that shape becuase of pascals law that force acting is perpendicular to fluids

@brando3342 4 года назад

Next video: "Honey! Now the neighbour is drinking from a ten meter long straw!"

@n0nenone 4 года назад

Finally, to understand capillary better than just theory from our SCHOOL teachers

@alexandrudanciu7874 4 года назад

This one was a proper explanation, finally. 👍

@asemhisham3507 4 года назад

Actually it was a very poor depiction of what really happens, the term relative pressure is only relative, and the entire explanation was lacking.

@phoenixamaranth 3 года назад

That's a nice detail about the redwood trees and explains why they grow only in coastal regions and why they are so large in California where the mist off the ocean travels inland so far.

@adriangaleron3293 4 года назад

Hey, nice video again, I like your channel for so long. Some people from abroad US can't fully understand you, and subtitles aren't very accurate, so when you mention the inspiration for your videos, like veritasium in this one, or Tom Scott in the last week "video about lasers" , some people won't really realize it. It would seem more fair to put a link in the screen. Thanks

@avarixzen6513 4 года назад

am I the only one who feels like he repeats himself on every point like 5 times

@stormtorch 4 года назад

That's how he makes sure everyone understands, even the people who consider themselves unexperienced at the topic at hand.

@TheBaseCam 4 года назад

He's definitely teaching! And your definitely observant 😎

@datbubby 4 года назад

That just reinforces any un-sure viewers knowledge on the subject

@superprabal 4 года назад

It helps to grasp the points better.

@alman8021 3 года назад

longer videos get more money

@nayankondapalli1075 4 года назад

Just know that unfortunately, a straw cannot be longer than 30 feet. My dreams have been killed.

@mpred8606 4 года назад

it can if there's already water inside of it since the beginning like how trees work although that means you d akready have water in your mouth so..... edit: oh it was already mentioned in the video

@alexandrudanciu7874 4 года назад

@@mpred8606, no... doesn't work... After about ten meters, whatever force you use to suck in, the liquid will not go up.

@DuelJ007 4 года назад

It sounds like the ten meters is only a vertical limit.

@cliveadams7629 4 года назад

@@mpred8606 Nope. Around 30' is the limit of water head at sea level. Doesn't matter if there's more than 30' water in the tube or you have a mouth full of water before you raise it vertical, air pressure can only support a column of water around 30' high and so it would fall leaving a partial vacuum above it. Capilliary action is a force generated between the liquid and the tube wall, surface tension limits the height the liquid can rise and the greater the diameter of the tube the less the surface tension can support a column of liquid under it. No negative atmospheric pressure there.

@mpred8606 4 года назад

@@alexandrudanciu7874 no I mean it wont work what I am saying is how like the trees from beggineng bassicaly have straws that get longer and longer it doesn't get stuck at 10m because there's no air ti cause tha liquid inside to boil its bassicaly in a super vaccum

@MarkWadsworthYPP 4 года назад

As I watched it, I kept thinking of veritas' tree video. Your explanation is simpler but better. Well done!

@lordpredator8855 4 года назад

I think Veratasium made a video for trees and negative pressure. Very cool.

@troywhite6039 4 года назад

Have you tried filling it until the capillary tube overflows but attaching another tube that feeds the overflow back into the large fill chamber. Would that cause a constant motion of it flowing into the fill chamber as it is pulled through the overflow tube via gravity and vaccum and capillary action forces all working in unison?

@Andy_M.S.c 2 года назад

wow that kind of blew my mind, now i must bother my prof during office hours and see what he says

@minercraftal 3 года назад

Got this question when as a kid, no teacher or anyone answers me why, first time got the answers here, sounds new and right to me. Thank you.

@R_BS-ug3ck 4 года назад

He really should start another channel where he teaches actually interesting chemistry and/or physics classes for high school students

@mtnman7776 4 года назад

Another great informative video and, THANKS for no distracting background music.

@allenscenery 4 года назад

Pressure is an emergent phenomena where molecules randomly colliding into one another at a microscopic scale. The natural question to ask is, what's going on at the microscopic scale for the negative pressure?

@asemhisham3507 4 года назад

The answer depends on your fundamental understanding of the term negative pressure, if it is understood as relative negative pressure then its essentially particles colliding just less frequently and with less kinetic energy compared to its surroundings. However if understood as negative pressure then unfortunately no such thing had been proven to exist.

@chanakyasinha8046 4 года назад

@@asemhisham3507 wht about negative volume

@charleswells9682 4 года назад

@@asemhisham3507 Theoretically, it may be possible in the realm of statistical thermodynamics, but only extremely locally and not at all on any macro scale. The caveat is however that the probability is so low as to be non-considerable. Thought conundrum: if all the molecules gather to one portion of a volume could the pressure elsewhere be less than what exists between the molecules natively? Of course, though, the question has no meaning.

@Owen_loves_Butters 4 года назад

Negative pressure means tension instead of compression. Of course you can’t have a negative force. The force is acting in the opposite direction, but since we use the word pressure to typically mean push instead of pull, it’s technically correct to say negative pressure.

@gogo311 4 года назад

That part about redwood trees was so cool! I had no idea.

@Eagles_Eye 4 года назад

flatearthers : " THIS IS CGI! WATER ALWAYS FINDS ITS LEVEL!"

@johnm5928 4 года назад

This was one of your best videos man. Thanks for posting!

@stevesloan6775 4 года назад

Awesome! As a kid I loved the Egyptian water level. As an adult I used it for a massive decking project to set all the uprights in concrete. It would be cool if the Egyptians actually used that type of levelling system. It might well explain a thing or two. 🇦🇺🤜🏼🤛🏼🇦🇺🤓🐇🍀

@Reuben-John 4 года назад

Water displays apparent "antigravity" properties all the time. Just think blotting paper or a drop of water hanging from a tap. Nothing to do with air pressures at all but just reminding us that molecular attractive forces can be much stronger than gravity. Air pressure is only relevant if we try to draw water up a pipe that is not open ended. As far as very tall trees are concerned I'm sure I read somewhere the extra lift beyond capilliary action and evaporative "suction" is achieved through a series of open and closed valves in the trees structure. I love your vacuum experiments and watch them regularly. Can you try this in your vacuum chamber - I'm keen to see the results.

@Horus2Osiris 4 года назад

try Rain-x, make your glass surface hydrophobic, redo experiment, measure differential coefficient of friction via your change in miniscus... You get the drift.

@motioninmind6015 4 года назад

Love it :) Wondering about the effect if the contraption was made of a hydrophobic material. I think it might be the opposite (?)

@h7opolo 4 года назад

i love this presentation of yours showing the capillary action phenomenon.

@Avengers24-sw7cv 4 года назад

The flat earthers should watch this, just so that they can see that water finds separate levels.

@enoch7thadam1st2 4 года назад

I can already see it: you have not thought about your comment properly. pity. look back and go to nature and see why it is possible what you see. because you think you can see but you only see what you want to see.. I do no reply.

@SuperPrDude 4 года назад

Read my mind.

@biologicallyawptimized 4 года назад

Flat earther's have already done their own experiments to prove the earth is round and have thrown out their own evidence. While this is a great proof against their argument, sadly they are doing science backwards. They already have their answer, now they need to find evidence to support it.

@alexei4204 4 года назад

Instead of glass, if you used a more hydrophilic material for the tubing (e.g. wood) would it pull the water up more? The reason I ask that is because the interface between water and any other material always creates a type of meniscus of some thickness which varies in size depending on how hydrophobic or hydrophilic the material is. The meniscus doesn't just happen between water and air although by definition the interface between water and air is given the term 'meniscus.' I'd be curious to see this experiment repeated with wooden tubing. :)

@DANGJOS 4 года назад

@The Action Lab Wow cool thanks! After I first learned about hydrostatic pressure, it always bothered me how water could push down on the water below while adhering to the side in extremely thin tubes. This explains that quite nicely!

@driverjamescopeland 10 месяцев назад

This is the same principle used to create the "lighter-than-air" material known as Aerogel. Basically, it starts as just a block of amalgam, until the liquid is evaporated from the voids. Once the evaporation has taken place, the voids are so small, the air pressure within the matrix left behind is of a lower pressure (amd subsequently less mass) than the surrounding air... so the matrix itself actually 'weighs' less than than sum of its true mass.

@sreelalithakaturi5814 4 года назад

Hi action lab 👋 i liv ur vids .. ur my inspiration and bcuz of u I was interested in science..U were the reason I decided to become an astrophysicist Im stil 15 tho... Hope u read and comment this(comment optional) Btw it says actionlab is closed! On ur store.. I really want to buy some stuff so can u open it again ... I am from India. Salute and hatsoff to u 😎😎😁😁😁😁😁👏👏👏👏👌👌👌

@NewbyTon 4 года назад

Thank, now i know how make below 0 absolute presure vacum

@MammaOVlogs 4 года назад

wow way cool, good thing straws aren't that long :)

@chinmaykalkeri 4 года назад

Loved this video, loved the veritasium video as well, thanks dude.

@anilsharma-ev2my 4 года назад

Bending the capillary will make some running Or siphoning will give some motion once it's starting Try this

@cousinles80 4 года назад

If you kept pouring it would the small tube overflow? If so could you run it back into the big tube and have a perpetual machine?

@TheChemicalWorkshop 4 года назад

After launching i was like, wait, didnt veritasium cover this? Great video !

@shivarajdolli5383 4 года назад

In trees not only the capillary force that help in taking above but the adhesive force also helps in that

@MuhammadDaudkhanTV100 4 года назад

Woo super nice experiment

@maksimgriskevic5446 4 года назад

I’m so sad that you don’t make a lot of videos I just find them so fascinating

@injesusname3732 4 года назад

i think its surface tension, not pressure

@MM-np4nm 3 года назад

The shape of the meniscus is caused by the wetting angle or the hydrophilicity of the glass capillary. With mercury the contact angle would be much larger.

@oliverracz8092 4 года назад

Thanks for dyeing the water!

@anjangaire6262 3 года назад

Wonderful analogy

@conswizzy710 4 года назад

with all the negative comments that exist on RU-vid, here is a positive one for you. You are awesome!

@MeFreeBee 4 года назад

Try the same experiment but using tubes made of teflon or some other hydrophobic material.

@Hablizel 4 года назад

This is one of you most fascinating videos. (I never realized how geeky I was).

@thebaddestogre-3698 4 года назад

Now make a perpetual motion flow of liquid using capillary action!

@linecraftman3907 4 года назад

It'll level out eventually no matter how hard you try

@thebaddestogre-3698 4 года назад

@@linecraftman3907 perpetual motion is impossible, It was a little humor.

@stomoxe1 4 года назад

Perpetual motion ? see the test : the liquide stop to mount... ru-vid.com/video/%D0%B2%D0%B8%D0%B4%D0%B5%D0%BE-Zj2cfihDrpU.html

@dumbcat Год назад

@@stomoxe1 i don't get it. can you explain?

@MichaelELambert 3 года назад

Depending upon the size of the tube will yield the pressure of the liquid! The larger the tube, the lower the pressure. The smaller the tube, the higher the pressure! Ranging from small to large in the tubes would be 2, 3,4, then 1, being the largest in size and 2 being the smallest, not counting the horizontal chamber connecting the vertical tubes! If the tubes were equal in size, then the pressure would be evenly distributed!

@jacobrollins37 4 года назад

This makes me want to believe perpetual power is possible. If only thermal dynamics stayed out of the way.

@loyki7076 4 года назад

Awesome video!!! Keep continue And most importartly... Stay safe

@lyn7591 4 года назад

Scientist: publishes law of science Action lab:im About to end this man's whole career

@amarafray5431 4 года назад

Archlyn 186 I can’t say how accurate this is

@maxsanchez4256 4 года назад

HUH. So... ever- flowing heron's fountain may be possible? maybe if the smallest tube was curved to feed into the big fountain it would flow on its own until it evaporates?

@mddelman 8 месяцев назад

Very informative video, thanks. Do you have time to answer a question for me? I have a small vessel filled with water. A thin tube (1.5mm inner diameter) hangs an arbitrary distance below the surface and the top is attached to a valve that allows me to release ink into the water. When the valve is open, ink flows freely. When I close the valve, a vacuum is created at the top of the tube, so the flow of ink stops. However, through what I assume is capillary action, water from the vessel is pulled into the tube, apparently displacing ink, which then leaks into the vessel. This continues until all of the ink in the tube has leaked out. My question is, is there any way to prevent this leakage from happening? I cannot change the viscosity of either the ink or the water. The tube could be modified if that would help, but not to the extent of using a much larger diameter tube. I hope you find this question interesting and I'd be most appreciative if you can answer it. Thanks very much!

@THEBATMAN28AHH 4 года назад

Hey Action Lab, one topic i know that's highly debated is how to clean a vinyl record. Some argue expensive machines, and others argue good ol' elbow grease. Think you can put this question to rest? How can we effectively clean a filthy record???

@PlayNowWorkLater Год назад

This seems like it’s borderline hovering in the realm of a perpetual motion machine. If the capillary tube, which has the highest elevation could somehow be directed back to the wider source tube. I’m guessing there is something in the physics about that distance you mention, especially showing how it retained that distance in the capillary tube after draining it. Just a thought, if the capillary tube had bends in it, would the liquid travel the same distance, or match the height from the previous experiment?

@triadxtechnologies 4 года назад

What happens when the glass in a capillary is coated in a hydrophobic material? The capillary effect would not longer work, correct? If that is the case, then materials that are more hydrophilic than glass should produce an even more dramatic effect?

@kelvinnueveanimeguitar1983 3 года назад

What if I cut the 2nd tube (highest) A little bit below it's highest water level so it starts to flow out and connect it back such that it flows to the 1st tube (biggest) Would that mean it would keep flowing?

@sebbes333 4 года назад

*@The Action Lab* 3:50 -ish. So if I would make like a 10 meter long garden hose, filled with some optimal material (like graphene tubes or something?) then I could lift water 10 meter straight up without investing any energy? Can't be right, that would violate the laws of physics? (conservation of energy or something). It would mean that I could take a mine shaft, lift the water 10 meters, pour it into a pool & repeat the lifting forever. I could theoretically lift it into space? FOR FREE??? Can't be right? That would create perpetual motion engines! Can't be right? But also, trees use this I think, in their stem to lift water? *WHERE DOES THE ENERGY COME FROM?!!*

@sebbes333 4 года назад

"He screams, as he slowly descend into madness..."

@wilgarcia1 4 года назад

of course my mind immediately wants to know if you can make the skinny path pour back in to the large one perpetually =P

@SundeepKP 4 года назад

Hey action lab, here's a idea for your next video,"try keeping water in a vacuum chamber and dipping the vacuum chamber in LN2". Please try it!

@Thrustql 4 года назад

*He knows how get much views* (lol) Me: *Watching in my recommended* The Actionlab: *How Make A Pressure Lower Than Absolute Zero Vacuum* me: HMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMM..THE THE TITLE VERY TASTY And thats how i got here

@nitrouspeed3583 4 года назад

Anyone wondering what if the thin glass were bent & poured into the big one?

@theninthab 4 года назад

I was waiting for someone to say that

@realflow100 4 года назад

Make enough of them connect together to form a drip that can fall!!!!!!

@melonenlord2723 4 года назад

Me too, but i think the capillar effect and surface tension would hold the drop together, so it can't drop. The force that is needed to overcome the effect will cancel out the gain of potential energy from the water height difference. But its only a guess. ^^

@jordanbwalt 4 года назад

@@melonenlord2723 Either way, it's definitely impossible, at least infinitely, as that would be over 100% efficiency, and we'd be using it for free energy.

@dumbcat Год назад

@@jordanbwalt humans know very little about the world around us, yet we are so arrogant we make up 'rules' that prevent others from questioning

@mkmuaqibizzuddin6885 4 года назад

Hey, you forgot a 'to' in the title

@nayankondapalli1075 4 года назад

Nice catch, my brain literally filled in the to for me and I didn't notice.

@Thrustql 4 года назад

yes

@destroyishere4655 4 года назад

@@nayankondapalli1075 Same.

@mitto.D.nimbaku 4 года назад

@@StevenAlexander44 the repeated ??

@harshit8189 4 года назад

I feel like he did it purposefully for some video later xD

@Boda.Attila 4 года назад

Interesting content as always. Thumbs UP.

@moodberry 4 года назад

I always enjoy your videos. So as a follow on to this video, can you explain HOW an WHY capillary action gets its force? What is actually happening at the atomic level? And one other question...are you a teacher by profession? What do you do for a living?

@TheActionLab 4 года назад

The force is due to the atomic attraction of the water to the glass through adhesion. it attracts it so much that it gives the water something to hold onto so that it can actually be under tension and not fall apart. Also, by profession I am a chemical engineer

@pedrobluis 4 года назад

Talking about negative pressure (omitting the RELATIVE) will get flat earthers pumping!

@AlexandruCzimbor 4 года назад

Hello!! Great video!!

@calistojupiter6418 4 года назад

Awesome explanation ♥️👏👏👏

@ketanmorajker 4 года назад

Just amazing example 👌🏻

@donut965 4 года назад

my new science teacher while on quarantine 😂😂

@paulk5670 4 года назад

Be very careful accepting what's shown here without a critical mind. As has been pointed out elsewhere there are fundamental flaws in the explanation.

@onradioactivewaves 4 года назад

5:36 " absolute relative pressure "😅

@dogwalker666 3 года назад

I missed that first time well caught!

@chanakyasinha8046 4 года назад

Meniscus are related to intermolecular forces between vessel and fluid... Cohesive interaction

@alexandrudanciu7874 4 года назад

Finally another scientifically video after of such a long pause🙄😊, All others were just... you know; not about science. (this one was good) 👍

@FrozenFox20 4 года назад

So if the capillary force makes the water level rise higher than the other water level what keeps you from flowing the water from the capillary tube to the other one to get perpetual motion?

@paul_artz 4 года назад

Can u make a infinity water loop with this stuff

@jonobjornholm 4 года назад

By embracing the dark side of the force

@Michael-mq5er 4 года назад

I have a question, if a black hole suck into it everything with mass, and if you placed a small black hole a question, if a black hole suck into it everything with mass, and if you placed a small black hole on earth it would suck in the earth as well as the air since it has mass, if it did what would be left except for the black hole if everything got sucked in?

@JoeytheJaguar_Lewcock 4 года назад

The force is strong in this one

@Owen_loves_Butters 4 года назад

This is The Action Lab’s most controversial video for sure

@uzairm3816 4 года назад

I was about to say this reminds me of Veritasium's video, and you mentioned it

@mariodistefano2973 4 года назад

You where talking of the capillary force for water. But if you put liquid mercury, instead of water, would we Have the same behavior? Mercury won't stick to the glass wall, so I suspect we would have the reverse behavior, isn't it?

@ntanimates9523 4 года назад

How does come up with soo many ideas mann he would be the perfect partner for a science fair

@choclate1243 4 года назад

You should try putting that thing inside a vacuum chamber and see if it affects the levels of water.

@JohnDlugosz 4 года назад

straw vs tree: I think that's not right. A straw is limited because if you remove the air from the top you still have the weight of the water acting against the weight of the atmosphere. Capillary action will work even without an atmosphere.

@cleitonoliveira932 4 года назад

I was hoping you could put more water in the tube so the thin part could overflow.

@Phosphene_Dr3am 4 года назад

I wonder what would happen/ what it would look like if the inner walls of the glass had some kind of a hydrophobic coating on them and you tried this...🧐

@AlexKing-tg9hl 4 года назад

That would have to be a pretty thin straw though to hold up that much water

@ektaagarwal9288 4 года назад

Please upload a video of stress strain curve doing an experiment ....

@radhiananamchowdhury5100 4 года назад

His ideas are revolutionary and unlike any other youtuber ever thinks of🤯🤯🤯

@coffeejohnny2337 4 года назад

I feel like this is the perfect channel to ask my question: Is it possible to pour soda from bottle to a cup without losing the fizz?

@Neubulae 4 года назад

Veritasium already had the answer for you: as long as you are opening it for the first time and there are no bubbles in the soda, you're on the clear

@MJazStudio 4 года назад

6:44 I was thinking if I should leave a comment about varitasium's experiment and you said it just at that moment😃

@frostgamer8371 4 года назад

You do the coolest things

@oxernaut1527 4 года назад

I want you to just take a moment and think about the two words “negative pressure”

@coolguy284_2 4 года назад

@G Guest Although this video showed that absolute pressure can in fact be negative. A solid under tension or a liquid that is also under tension but not allowed to cavitate are examples of negative absolute pressure.

@charleswells9682 4 года назад

@@coolguy284_2 I'm not at all sure that pressure in a fixed lattice has any meaning.

@paulk5670 4 года назад

@@coolguy284_2 I believe you're confusing pressure, a scalar that exists at a point and acts normal to surfaces, with stress, a vector that has magnitude and direction. It's a common mistake because they both have units of Force per Area. But whereas a negative stress makes perfect sense, negative pressure (in an absolute sense) simply does not.

@coolguy284_2 4 года назад

@@paulk5670 I'm just referring to negative pressure the same way some people would think of negative speed, going backwards to the expected direction. The same way people talk about negative relative pressure (outside greater than inside), you can talk about negative absolute pressure (outside greater than inside but outside == 0). Even if it's a mistake, it has one and only one obvious interpretation, and since people already talk about negative relative pressure, it shouldn't be too much of an issue to talk about negative absolute pressure instead.

@paulk5670 4 года назад

@@coolguy284_2 Except that you're missing the importance of the word 'absolute' in terms of pressure. Pressure is an emergent phenomenon from the random motion of molecules, same as temperature. Absolute pressure means you're starting the scale from no pressure at all. (as opposed to gauge pressure, which typically starts the scale based on the local air pressure being 0psig, approximately =14.7psia at sea level) Just as it makes no sense to have a negative absolute temperature, so too it makes no sense to have negative absolute pressure. Or negative volume for that matter. The ideal gas law relates these quantities: PV=nRT. You can have changes in values that are negative but none of them can actually be negative in and of themselves. How do you get colder than atoms not moving? How do you get a lower pressure than atoms not exerting any force? How do you have a volume smaller than zero? How do you have less than zero atoms? In short, you can't. (R is just a constant that makes the units work out so its value is what it is).