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AMAZING! Ferrofluid + Glow Sticks
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- เผยแพร่เมื่อ 19 ต.ค. 2015
- Ferrofluid is a liquid that displays unusual properties in the presence of a magnetic field. Watch what happens when we mix ferrofluid with the liquid from a glow stick!
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This is why I love Science, even when you think you know everything about 2 separate things you can always find a way to mix them together and create something new.
Brilliant!
Ça fait plaisir de te voir ici ! ;)
Ferrofluid lava lamps now!
+Lucas Balaminut It's been done. www.kickstarter.com/projects/1880422811/ferrofluid-a-symbol-of-the-future/description
Inspired Designs OH HOW AWESOME! Thanks so much.
+Inspired Designs That design is somewhat..... crap and short sighted. If you have what is basically a lava lamp setup then why force folks to mess about holding magnets to get a result. Why not simply run a rod up inside it and have it activate as an electromagnet. Hook it to something like an arduino with a program and you can have pulses and patters of magnetic waves causing the basic lava lamp to take an evolutionary leap in what it does.
I have a ferrosand hourglass
+Bean Sprugget that would be awesome!!
This channel is easily among my top 5.
Your videos are awesome
Just wanted to say thank you this is so cool for my 7yr old daughter, when I have her for my visitation I think she will really like this again thank you and God Bless
You should get a Patrion account.
So far I haven't seen a vid of yours I haven't liked.
My daughter's response to the warning at 0:24 - "I want to try this at home!"
Why a finite number of discrete spikes? Aren't fields supposedly continuous?
+David Battle It's the Feynmans Double slit made visible in Makro Scale. This is Nobel price stuff!
+David Battle You recently see the detected scan render of the field rings coming out of earth? they're not continuous. quantum hax i think is your answer.
+David Battle
I like you, you look like Mr Potato Head.
+Kaironex Cryziz Can you send a link to this? It sounds very interesting!
+David Battle First things first: There is no way that any quantum effects are visible at that temperature and without vacuum, it is a purely classical effect. Moreover we have a static phenomenon, so any explanation using waves (which are not static) cannot be the answer.
I've found a likely explanation further down in the comments*. The magnetic field is not homogeneous, which means that the fieldlines point away from each other, so the liquid is pulled apart. When liquid is pulled apart you see effects from the surface tension (e.g. water building drops) which cause it to cluster.
So in a sense the spikes are drops pulled from the liquid. This is a simplified model for the forces that act on the liquid, but I think it gets the general point across.
*credit to +alcaz0r1
That looks so cool!! Love your videos, always so interesting and easy to understand. Thank you for your work Dianna!
I want to elaborate a bit because I see some people are still confused as to why the ferrofluid spikes the way it does. She said they point along the direction of the magnetic field lines, not that they align to them. I think that's the source of confusion. The magnetic field is continuous. The distance between the spikes is determined by both the magnetic field and the surface tension (as well as some properties within the ferrofluid itself such as magnetic susceptibility.) It's a balancing act between many forces and the spikes are energetically favorable. It is not the manifestation of randomness. I can perform an experiment to demonstrate this if there is interest.
My favorite parts of your videos are when you discover some new interesting and unexpected phenomenon! Keep up the great work :)
"There's so much physics happening here!" ... Really, can you think of a single situation where there ISN'T a bunch of physics happening?
My explanation for the appearance of spikes: - The ferromagnetic particles become tiny magnets and align themselves in the direction of the field. This means that at say, the magnet's North pole, they stack up with each particle's North pole joined to the next particle's South pole, in a chain aligned with the field, pointing away from the pole. However, this means that at the end of a bundle of chains, at the ferrofluid surface, there are many North poles next to each other with no attached South poles. Since North repels North, the bundles of chains are driven to repel each other, while surface tension draws the surface inbetween them, and they split into spikes, rather than terminating in a smooth dome over the pole.
I love your examples and experiments of concepts in physics. I have a degree in physics, yet often I wasn't sure how the concepts I learned could be reflected in the physical world. I really appreciate your videos for that reason. :)
I love seeing the reaction-diffusion pattern that forms after the field's removed.
This is too cool. I could watch this all day!
+TH-cam Aneesh Me too! This is one of those videos where I actually enjoyed watching all of the extra footage while editing. It's so pretty!
+Physics Girl Awesome Video ! Thank you Physics Girl ! Do you plan on Going to France someday like for a convention or anything ? Or switzerland ? CERN maybe ?
Last time a girl told me to meet her in a garage I woke up in a bathtub full of ice with a missing kidney.
I've seen some really cool sculptures with ferro fluid.endless posibilties with this stuff.
thank u physics girl. I set that Oefner's art work as my desktop background. so one day that I had a presentation, my prof. asked me about it. and I couldn't explain the hydrophobicity correctly and he mocked me for it.
Now I have a good explanation! tnx
I'm so glad I found this channel. Thanks for the video.
I'm being the 2nd. Hey, Diane, just to thank you for making such awesome videos of physics. I myself am a great fan of physics and its supercool awesomeness, so thanks again for making such beautiful videos.
Last part with the dry ice was really cool. Could it bee that when you held it there it melted a spike pattern into it, making it's most comfortable position on those spikes that fits. And then the rest of the spikes around it works similar to a Leidenfrost effect to push it upwards?
Would love some in depth explanation of this though =)
I'm just happy to hear you pronounce the word "experiment" correctly. That might sound strange, but you would be surprised at the number of hosts of "science" channels which get it wrong, including Hank from SciShow.
+Skeletor Jopko I watched 4 times trying to find her pronounce "experiment" but I can't find a single instance. I'm going to have to watch all her videos now!
Katie Gilligan 3:29 in this video.
+Skeletor Jopko You mean when people say "expeeeriment"?
Matthew Henderson Or, as Hank Green pronounces it, "ex-spearmint".
Do we know how ferrofluids behave around magnets in microgravity?
+Jennifer Serene i don't think that gravity play a big role in this experiment. Ferrofluid particles just align with the field lines.
+Jennifer Serene Am not sure, but i think ferrofluids react to magnets just because the fluid has iron in it.
+Baptiste PARIS so do you thing that in microgravity ferrofluid would just form an orb around a magnet, or would you see it streaming out following the magnetic field lines?
+Jennifer Serene i think the surface tension of the fluid would prevent the spikes from streaming out and follow an entire field line. We would see just what we see in this video.
But this is the theory! A real experiment could make us say "hey, that's cool! That wasn't expected at all!"
+Jennifer Serene It has been tested in space on the ISS, for some reason it was just a suspended blob with no spikes. The magnet just moved the blob around slowly.
I was at the MIT museum this past weekend with a few students.. and there was a photograph taken of ferrofluid on the microscopic level.. i let my mind wander and remember thinking: maybe there is a field that binds all matter together in a similar way and that if you were able to remove the field.. all matter would lose its attraction to one another and turn into an unrecognizable goo just like this ferrofluid.. that there is something inherent within matter that reacts with the field in a particular way that gives rise to protons and neutrons and molecules and all the rest..
and then you post a video of ferrofluid a few days later.. very nice! :D
Very nice video... The observation with the dry ice is really a curious case. It reminds so much of the Meissner effect, but the puzzle is that carbon dioxide is not a superconductor at its freezing point. I gotta do this experiment.
Why can't we try this at home?
I don't know how hazardous nanoparticles of metal are for you. But mainly, it's the chemicals in the glow sticks that are not good for you, especially not for kids who often watch my channel!
+Physics Girl And is it messy or what!!
+Physics Girl yep. Most glow stick chemicals will cause rashes and irritate skin. Also, not a good idea to try to make glowing lipstick with it for a female friend.... I wouldn't know though....
+Physics Girl And break the glowstick from they suvivalist parents...And then blame YOU!!!
+kcthewanderer you can try this at home i have, make sure you have the proper setup (i.e. snorkel for poison gas removal and a solution concentrate to dilute the solution you make)
I'm totally trying this at home...
Your videos are the best on youtube
I have a hypothesis for the dry ice suddenly switching direction.
I think it's happening because the ferroliquid freezes and then sticks onto the dry ice, which means the whole underside functions as a magnet that is then attracted to center
in the late 80's and 90's it was used in tweeters and mid range speakers to keep voice coils cool and to increase power handling
+Physics Girl My dad is a highschool physics teacher and I had him as my physics teacher when I was in highschool... and my older sister was in the same class as me as well!^.^
Anyone got an explanation for the observation with the dry ice? That was really cool!
+FartingNinjaFrog I'd like to hear one too!
+Physics Girl so the magnetite particles are suspended in a fluid medium maybe that medium crystallises and binds with the dry ice suspending the magnetite in a crystalline medium forced in a pattern that corresponds with the magnetic field lines and that might be why it reverts back to position it was in before
+FartingNinjaFrog
Hypothesis: When you hold the dry ice on the ferro fluid the nano particles are frozen into a particular magnetic arrangement against the surface of the dry ice. If this is done long enough for a large number of particles to accumulate in alignment with each other they will create their own magnetic field (just like how molten iron can harden into a magnet when allowed to solidify slowly in a strong magnetic field). These frozen particles then interact with the field of the magnet below the tray and drag the dry ice (which they are frozen to) back into alignment with the magnet.
To test this, after this effect establishes itself you should try removing the dry ice and see how much ferro fluid is sticking. Next flip the magnet over and test weather it now repels the CO2/ferrofluid combination. Likewise you should be able to stick the CO2 (with the ferrofluid ice magnet side) onto the permanent magnet. You might get ferrofluid on the magnet but such is the price of science.
...Maybe put the magnet in a plastic bag before trying this.
+Physics Girl The dry ice likely only repels the ferrofluid due to out-gassing. Ferrofluid sticks to surfaces notoriously well. It likely began to stick to the dry ice as you left it in place and one the ferrofluid began to embed itself in the material it will make it attract to the center of the magnet.
By the way, we are experts in making ferrofluid displays and would love to collaborate on something with you if your open to it! Or just donate some stuff for you to experiment with.
+Inspired Designs send me an email! dianna at physics girl dot org
This video was so informative. I liked the explanation for how the ferrofluid worked.
honestly i have learnt more interesting stuff and better in the 3 weeks ive watched of your vids than my whole physics unit about certain liquids and their behaviours... and for this i thank you, alot. I have an avid interest in physics and chemistry and im just about to start my A-levels studying them. :-)
also there is a 2018 CERN trip, I can't wait!!
I've already done some projects with this fluid. they're very cool.
if you have a powerful enough magnet and some ferrofluid, could you make spikes that could potentially pierce skin? That'd be pretty sweet for SO many applications....... like the T-1000....
Just for the record, magnetite is not a metal. It is an oxide with the formula Fe3O4. And what really disturbs me is that no one seems to have noticed it.
F = q(v x B) and T(surface tension)=(h*rho*r*g)/2 put into F=ma
Holy crap that's a lot of physics. I love it!
we got to play with metal filings + magnetic fields in school. That was cool, don't get me wrong, but it was 2D -- the metal filings are on paper. The 3D aspect of this really adds to it. Let alone mixing in the glowstick stuff. Good job!
When the magnet is too close, filings tend to clump around the edges of that magnet and may fall flat due to gravity and mixing with fields on the sides. Pull the magnet away a bit (add a board under the paper, if necessary,) and the inner fields will be more prominent, allowing a more compact crown of filings to stand up better against gravity. The ferrofluid shows this because its surface tension and thickness usually keep it from thinning out and clumping around the edge the same way.
You might also have had too much iron mass for the size of your magnet, to be able to see the spiking effect. A little sprinkle is generally enough to play with, but fun stuff can be done with more, too.
it was cool to see how the magnetic field changed as the magnet got closer. it seemed to change the ferrofluid from something resembling a brain to looking like a fingerprint to finally spikes.
I liked this video mostly because I thought the last few comments on dry ice behaviour were cool as.. Thanks for your work! :D
I was already the favourite Uncle .. cannot wait to blow out a candle with an "empty" glass & watch the wow in their eyes ..
Thanks :)
Amazing shots, i will pick up this idea on my macro channel:) Thx and Cheers from AnotherPerspective
THIS IS SO COOL! I adore you so much!! :)
I dont know why but seeing that gave me chills!!!!
You explained ferrofluid so much better than most channels
You rock! Subscribed.
Brains and beauty :)
Why have I never seen your channel before?! Omg. This is awesome ! Subbed. :D
3:20 There's a misconception that ferromagnetic powder and ferrofluid tend to group into the magnetic lines. There is no discrete number of lines to be "grouped into", instead there are infinitely many lines and the ferrofluid only aligns with them. I don't fully understand how it works, though. It would be awesome if she made a video about it.
So alien / awesome! Thanks for the great explanation.
Wow. You just made Feynmans double slit pattern visible in makro-scale!
This is very similar to the Messiner Effect.
The dry ice and its cold temperature was expelling the magnetic field but not the magnetic fluid and it was riding an induced electric field generated by its own cold temperature. This acted as an electric conduction motor of sorts and the ice moved on its own to the center. This is very educational if you want to teach about electromagnetic fields.
If the ice was any colder it would have started levitating at the center where the magnetic field lines are most numerous and therefore strongest.
What's the song that starts at 0:34 ??
Great video btw, would really like to understand the dry ice behavior.
A wild guess as to the ferrofluid observation: I think some of the ferrofluid froze onto the dry ice, making a dry-ice-cum-metal lump. The metal end of the lump wanted to stay near the magnet, at the top of the mound, so it was attracted there. It stayed on top due to the relative density.
This is really amazing!
Do you have more Photos like this??
Imagine this being a screen saver :D also I found your channel not that long ago and I love it keep making awesome physics videos !!!
That is so interesting and cool! When the spikes form, are they hard like a nail or pliable!?
I just love learning ❤️
Questions:
What if you touch it?
What do the spikes feel like: Solid or liquid?
What if you ate it?
How is this found?
What if you mixed it with lead?
Can you make slime with it?
How am i supposed not to do it RIGHT NOW!? that was beautiful
I saw this done with what seemed to be a cone with a long strip of electromagnetic wound across it, to the end. The result was like nothing I'd ever seen without the aid of a CGI.
BE WARNED!!
There is a jumpscare at 1:17
Dianna, does the dry ice "going up hill" have anything to do with Flux pinning? en.wikipedia.org/wiki/Flux_pinning
Kinda like that lexus hoverboard that uses liquid nitrogen?
I've seen something similar done with dish soap and pulverized iron filings.
MORE ! I want MORE videos ^^
On a serious note, these videos are really great. Congrats ! Ferromag fluids have a lot of interesting properties, and we still don't know/understand many of them. I'm sure applications will be found with it.
+Ezor There are many applications. The list below is from ferrofluid.today/pages/what-is-ferrofluid
Cooling in loudspeakers for better sound, Liquid O-rings for making computer chips, Magnetic hyperthermia for better chemotherapy, Targeted drug delivery for cancer treatment, Shape shifting mirrors, Space craft propulsion, Keeping you curious
I really feel like some kind of electromagnet array thing should be put together, put under the ferrofluid (with the glowstick goo). Then you could feed a music track into software controlling an array, and have a physical music visualizer. Should do that...
Awesome stuff! Would it be possible to make a magnetic gas if enough particles were airborne?
Quality. Diana Cowern on a mission to get girls I to Physics. And us guys too. Her videos breath fresh air. Just proves your enthusiasm will rub off on your viewers
Interesting... the tendency of the dry ice to move back to the position in which it was held is very similar to superconductor "flux pinning." If I were to hazard a guess, I would say that the dry ice cools the ferrofluid surrounding it, fixing it in place on the dry ice surface and locking in the magnetic moment of these particles. Because the magnetic moments are aligned with the external magnetic field at this position, if the dry ice moves, it will bring some of the particles out of their desired alignment, creating a torque that would resist this movement.
+James Endres Unlikely. The ferrofluid is not nearly cool enough for superconducting behavior.
+Mod MINI I agree. I was not trying to say that the ferrofluid is becoming superconducting. I was trying to say that this may be similar to "flux pinning". With a superconductor, flux pinning occurs because eddie currents in the superconductor generate magnetic moments that align with the external magnetic field.This then causes the superconductor to resist a change in orientation with respect to the external magnetic field. In the case of the ferrofluid, the magnetic particles within the fluid, would align their magnetic moments with the external field and then the dry ice physically freezes them in place, where they then resist a change in orientation. It is the same idea as flux pinning in a superconductor, but it would be caused by a different mechanism.
+Mod MINI Not cold enough for certain old style super conductors, however they keep discovering materials that work at higher and higher temperatures. Also theoretically there can be room temperature super conductors, and lots of scientists have spent much time and effort searching for them...
My guess is that it rolled back to the top because it had ferrofluid on it, so if it was on top of what is more or less a friction-less surface { suspended on points } the ferrofluid on top of the chunk of dry ice would be enough to pull it to the top to follow the field lines
The question I have is: How does the magnet get so cold when conduction is limited to the surface contact between the dry ice and the ferrofluid { essentially just a few points } ?
the dry ice could induce a higher conductivity in the magnetite, strengthening the field and locking it in place.
That was absolutely awesome. :) I'm really tempted to break out my ferrofluid goop and try this.
+The Gentleman Physicist Your ferrofluid/superconductor video was pretty cool too. :)
Glad you liked it. I'm hoping I can finally get back to making videos now that I've landed gainful employment again. :P
The magnetic field lines drawn at 1:32 are confusing. They seem to be going both counter-clock-wise and clock-wise. The center lines are going down, so wouldn't the right-hand rule indicate that the side lines should only be going clock-wise? Are the lines correct and my understanding of magnetic field lines incorrect, or is something else going on?
OMG that's so amazing!
That's how it should be shown in schools :3 Awesome!
I didn't really understand the spike explanation. The part about the spikes lining up with the magnetic field lines.
If I don't think much about it, it makes sense, but after some thought, I remember that magnetic field "lines" are just a visual representation of the magnetic field. There aren't actual lines in real life, just a field of magnetism.
Essentially a vector at every point in space. And if it's at every point in space, there would be no lines for the spikes to follow.
I can accept that the spikes point in the direction of the magnetic field, but what causes them to be individual spikes that are separated? Why do certain regions rise, but others do not?
Rather than using a chemiluminescent material that will soon fade, how about some sort of fluorescent fluid(s) and an ultraviolet light?
I don't understand the science but this is cool af, same as pretty much all the other videos I can't understand physics well apparently but it's still cool
Is it possible to do Flux pinning with "ferrofluid"?
The ferro would have to be a superconductor not Iron, and the fluid would need to be something that remains liquid below the threshold temperature for the superconductor.
Would there not be enough stuff with a 10nm thinger for pinning?
Wait, it rolled up the fluid? Do you know what this means? LEVITATION!!! Seriously, supercooled magnets and semiconductors is the latest science on that, and you have supercooled a magnet right there.
+Holobrine
this was my first thought, too. But why does this affect the dry ice? Usually only the magnet is kept in place or levitated.
I think holding it onto the fluid creates a smooth shallow cavity at the bottom of the chunk. And it's just geometry from there. No?
I wonder if the dry ice incorporated (froze) some of the ferrofluid, which caused it to eventually "roll up hill"?
Wow that looks awesome!
So... Totally... Awesome!!!
I wanna try that.
What's the point of the glow sticks anyway? apart from it looking cool? Aren't the glow stick fluids not doing anything particularly useful except for following the crevasse made in the ferrofluid by the magnet?
Ok, ambientalist question here: how do I dispose of the ferro fluid and the shinny liquid when I'm done with the experiment? I don't think it is okey to throw it in the sink.
now i have to reasurch vander walls force haha sweet vid!
So the magnetic lines of force that most textbooks insist are imaginary causes the ferrofluid to spike. It is also these imaginary lines of force when crossed at right angles with a conductor such as copper produces electric current. If these imaginary lines of force have such properties, how imaginary are they?
Ever see a magnet placed on a CRT screen? There would be another hot topic for a video. Magnets are one of the least understood phenomena out there.
Which came first, the electric current or the magnetic field?
They're good at slight of hand.
+Physics Girl
What would be your best explanation for the "roll up the hill" effect?
I think that maybe the cooled down magnet has a diminished magnetic power in the area near its center so the spikes create a plain surface or even concave for the ice to stay.
Could that be the case?
This looks so cool!
Physics Girl -
Hey awesome video i'm a subscriber now! where di dyou get the idea to mix the ferrofluid with glowstick liquid?
aweosme vid
Why is there magnetic lines instead of like area or aura or something more "fluid" like?
+BaseFook What do you mean
+BaseFook The reason is the same as on Feynmans Double slit experience! This is Noble price stuff!
+BaseFook Good question, I've been thinking that myself lately. I mean the lines we draw for a magnetic field are just to represent the field. Why doesn't it just form a dome or aura like you suggest?? No help from me sorry!
+Make Science Fun You can see the aura here; th-cam.com/video/kmKMIBvdm9M/w-d-xo.html at 42 secs.
Then you can compere your findings on Feynman double slit experiment results; both slits oben, with or without light. Without light it's the peaks, with light it's the aura; like on the video link in this comment.
+BaseFook You recently see the detected scan render of the field rings coming out of earth? they're not continuous. quantum hax i think is your answer.
Very nice! What is the music that was playing between 0:40 and 1:15? I could watch that sort of thing for lonnnnng time, the patterns and colors are mesmerising.....
That would be such a cool sci-fi effect in a video game !
Oh, ferrofluids, what a mess they are to clean up after you've played with them :p
As for the dry ice thing, my guess is that the piece of ice is first repelled because of something similar to the leindenfrost effect : the gas generated by the ice piece pushes it away from the liquid, but if you first cool your liquid, the gas generation become slow enough that the surface tension of the liquid wins.
Also, I'd like to know where does that little song that plays at 0:04 and 1:59 come from? It's the theme from a science radio show that I enjoy listening to and I'm surprised to find it here. It's just out of curiosity. Don't worry, I am not accusing you of infringement :)
Thanks!
+supersmashsam I agree - I hate the stuff! Oily, black and messy.
But why shouldn't we do it at home? What's dangerous about it?
thats awesome. i'm also interested if that fluid could carry electricity and why not if it cannot... i could google it, but i like her answers a lot better, haha.
This is my new favorite channel.
Awesome. Love all videos... Keep going...
Did you ever do a follow up to why the dry ice reacted like that?
How long the glow stick light last? can it mix with the ferrofluid?? can it last for 5-7 days still visible in the dark?