Cold Welding Metals In a Vacuum
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- Опубликовано: 1 окт 2024
- In this video I show you how it is possible to cold weld metals together in a vacuum. I talk about galling vs cold welding and how it caused problems on the Galileo Spacecraft.
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At 7:20 I definitely did not mean Celsius I meant Fahrenheit, lol. I don’t think I’d be very comfortable in a 60 degree Celsius lab.
Ok.
xD you deserve an Oscar
Was just about to comment about that 😂
hahaha i did actually thought what are u saying
love from india bro❤️❤️
Pin that comment or you a lot of comments about it.
So when I push these two pieces of aluminium together, they should stick together.
But they don't. (Vsauce music).
Blah blah blah, right?
WRONG!!!
Or.. Are they?
mathologer, Action lab and Vsauce 2 ❤️❤️❤️
Are you sure this is cold welding and not friction welding? When you put them in the bag and the bag squeezes them, you could have a little bit of friction that could raise the tiny contact points above 85deg. You should put them in the freezer for a while and then try again.
@Joe Duke I’m aware cold welding is occasionally use of space experimentally, my point was that this is not cold welding. This is friction melting gallium which then cools and fuses the pieces together
Given the melting point of gallium is under 30° C, the slightest friction may cause spot welding.
Friction welding.
Exactly what I was just thinking.
The problem with welding gallium together is that you have to superchill gallium to get it to resolidify. It will stay melted down to pretty low temperatures. I have some gallium that I have to put in the refrigerator for several hours to get it to change back to a solid. It will very slowly crystalize even when it's ~5° C
The thermal conductivity of the metal is too great to allow heat buildup at the contact point with slight friction.
you have to realize it has to cool back down
I asked for this is the comments ages ago, never thought he’d get round to do it! Great video as always.
I messaged him on twitter about this too some months back and he he replied he is a good person
Same here kid
Same here, i asked him to do it 2 years ago and he did it now.
oh really? wow , way to go
Who asked?
Great video! Two questions:
1) For the vacuum chamber test, wouldn’t you need to remove the oxide layer that is already present on the surface of the two metal pieces? Just putting them in vacuum does not remove the oxide that is already there
2) Would an inert atmosphere (nitrogen?) work instead of a vacuum?
IME: yes, no. 'twas argon though, no means to try n2. It's freaking wicked hard to find LN2 in this city of five mill nutjobs, I don't get it. "Most of our atmosphere? Sorry, we don't carry that. You want a bunch of a highly unstable fuel, dissolved in acetone, in a tank full of concrete for super cheap, though? Comin' right up!"
Strange having no mention of having to buff off oxide (sulfate, etc) layers to cold weld. Props for knowing stuff, stuff knowers ftw!! So yeah, big time yes to that...unless you're cold welding fine gold or something, then you can just wipe it clean first.
I suspect n2 wouldn't do anything. Moreso than argon or any other noble really. Stuff I can pretty easily cold weld with the same process in an ultra high vac regime, does nothing of the sort in a vessel thoroughly purged of air and filled with Ar. I'd imagine inert gases present between the pieces meant to be welded would do what it typically does: be inert, and occupy space between the metals.
I wonder if you could _pressure_ weld gallium(for instance)? Not like smashing two pieces together, I mean like putting two pieces in an *extremely* robust vessel and pumping it to 1500 bar or something. That'd be cool.
@@phxgen Very interesting, thanks!!
@@phxgen
Just buy liquid nitrogen and let it boil?
@@lucaslucas191202 That's the problem, I haven't (yet) found anyone in this city that'll fill my little dewar. The only place I've found thus far that'll sell me LN2 is like 45min away & they won't fill my dewar, instead they want people to rent their enormous dewars for like $850 & up.
but... removing the air doesn’t magically make the oxide layer disappear? it only would keep it from forming after forging
That’s why gallium/indium is being used IIRC
Yea, I was wondering why ActionLab didn't remove the oxide layer first, but then I remembered that he would have to do that *inside* the chamber with a full vacuum pulled, which sounds like it would be ridiculously difficult haha. He would probably need a much bigger chamber, along with specialized tools/gloves that could be controlled remotely, which I'm pretty sure only a professional laboratory could pull off.
Oh well, I'm sure that somewhere out there is a cold welding video with a truly accurate demonstration :)
@@theoverseer393 I thought he said that gallium has *less* of an oxide layer, not no oxide layer, but maybe I'm wrong.
What confuses me is that I don't think the titanium antenna on that satellite was being squeezed by anything, so how could have cold welded shut if this demonstration is accurate to what happens in outer space?? Even with the squeezing, the gallium in this video was barely welded together, so how could a titanium antenna get welded stuck just sitting out in space, without any outside pressure on it? I thought it must be because the oxide layer on the satellite had been ablated by solar radiation, while the gallium in this video still had its oxide layer. I've tried looking it up to see if I'm right, or if there is something else going on, but I can't find anything.
Thats why you need to twist and press to scratch the metal to get it off
@@wolfsiejk yeah... oxides are SUPER hard - simply scratching or twisting the metal won’t do that
James in 2040: Today we're going to merge Sun and Mercury together and see what happens
you think humans can survive that far while Covid is here
@@deadski8860 COVID will either last and end next year or it will go on for a long time but with very low cases for the next 3 or 4 years so we will have to see
@@mlgklipz2543 Nice to hear!
@@deadski8860 well we survived ww1 ww2 and black death I think covid is kida small compared to these all.
more like 2400
But the gallium was already in the air so it already had an oxide layer, putting it in a vacuum doesn’t make it go away. I don’t get it.
Watch the whole video (he mentions it twice). He chose gallium, because it doesn't oxidize readily so those pieces were still mostly pure gallium on their touching surfaces.
I'm skeptical about whether you were able to actually cold weld. My understanding is that for cold welding to be successful, you have to get the surfaces scrupulously clean. I wonder if what happened was that a vacuum was created between the two pieces of metal and the edges were so well sealed that air could not get in. You probably had about 1.5 sq-in of surface area there, which would mean around 21 lbs of air pressure. When you take new microscope slides out of the package, they will stick together because they are so flat that the air cannot get between them. (Idea for an episode?)
High karat weight gold should be easy to cold weld because it has no oxide layer. Would it work to put a sheet of gold leaf between two very flat silver ingots?
Those surfaces were crude af, so I doubt it could have been held together by a mini vacuum. Maybe grease held them together
He said dissimilar metals have different crystalline structures so don't work. But by his theory, 2 gold ingots that are dead flat and smooth, and clean should work. His attempts were relatively filthy from fingerprint sweat/oils let alone not totally flat for good contact. Pretty poor excuse for a lab experiment.
The two ingots still had the oxidized layer from being exposed to the air previously. That layer does not just go away from being in a vacuum. The oxidization had to be scratched off on both ingots by mechanical manipulation. Only a few small scratches were made and connected which is why it was so easy to pull apart.
@@Newt2799 right but I think he was thinking about the possibility of the bits being vacuum sealed together instead of actually being cold welded
Yes, it looks more like wringing gauge blocks together.
I learn more in this than university
why do i see you everywhere
Lol, I know why he is everywhere, he posted it on his RUclips, but lol the comment itself made me laugh
You should go india and take 8th grade because it was use to teach kid in 8th grade in india LoL
university is just as bad as high school?
Wait....did you say that this concept is given in 8th standards books....stop kidding man....it's definitely not...
man i was so sccared about your fingers getting stuck inbetween the 2 monster magnets
i was gritting my teeth. little Neodymium magnets can hurt you.
@@markusgarvey I usually pay extra for them to hurt me
@@youtube.commentator Kinky.
no you weren't
@@sleepful1917 yes I was
7:17 Shouldn't it be Fahrenheit?
Galium melts at 29,76 °C
yes clearly fahrenheit.
I'm pretty sure he'd be dead if it was 60°C in his room.
@@jamesbrown99991 heard of a sauna?
@@GammaStyleGaming lol that depends on the core body temperature, if your body temperature gets to 60°, you'd be pretty dead
@@matiasivanarevalosbenitez811 yes but we were talking about ROOM temperature
I don't think they were bonded at all. There is a pocket in each puck, you created a vac between them that held them together
Indium to Aluminium: You don't have the Gall to join in the open.
-
Aluminium: Your bad jokes can't foil my plans.
looool
This is so cool! I have an oral presentation to do at the end of my year and your channel is a gold mine of intersting science phenomenons. Thank you for the inspiration! Love your vids
Watch Tom Scot
Tis is also the reason why in slow moving mechanics like in clocks where you can't reliably get an oil film in between moving gears then instead you make the gears out of different materials. It's not because brass is cheap as some people might think. It's because the alloy brass (copper and zinc) won't cold weld with steel (iron). The result is that you get a clock that lasts for generations. Had all gears been made out of the much stronger steel it wouldn't last as long as the steel would grind away because of cold welding. Naturally the largest gears are made out of the softest material as that causes gears to wear more evenly.
Hey Action Lab, put ice cubes in your vacuum chamber. Let us see what happens.
They will just melt....😂😂...why does it seem interesting to you....there will be nothing worth significance
@@ADVERSE04 shut up
@@marsen7350 shut up
@@tuyiren781 😂I don't know why people find it interesting.The ice will just melt that's it what do they expect the water to flow or something😂 ,well this is a common misconception among people that gravity doesn't work in no pressure areas
@@ADVERSE04 you must be a fun person
The attraction between the large neodymium magnet and the even larger magnet neodynium magnet through the glass was like _a desperate boy wanting to meet his crush_
Lol
What about wringing gauge blocks together? Is that cold-welding or galling? 🤔
Both as they're basically the same
Neither it turns out, check the sixty symbols video on it. It turns out that its just that when you make metals extremely flat to the eye, then when you push them together, they form microscopic suction pads, like the kind that hold your phone holder to your car window, just microscopic. They verified this by adding oil to the surface, and a bit like licking your suction cups, that improved the bonding. If it was cold welding, the oil would stop it working, and secondly once you joined then pulled apart your gauge blocks even once, you'd have microscopic mountains and valleys from where it didn't cleave cleanly, so it wouldn't work twice.
Gallium melt at 85° F, not 85° C. Your house is very hot if it's 60° C in there.
60°F
3:46 that "close" sounded like it had some autotune on it, lol
Lol yeah
@@fhsjdjskkshi BREUH
Dear lord, I love your experiments, but your methods and explanations are so poor sometimes.
1) Gallium still has an oxide coating that quickly and completely coats the surface, it's just that it is a much thinner layer than other metals like aluminium. Any welding seen would be because the vacuum can depress the melting point at local high-pressure sites, and so cause micro-welds where mechanically the oxide layer was worn off by rubbing.
2) When you extract air from a vacuum bag, you don't reduce the air density (air pressure) at all. The pressure from the atmosphere is enormous, so you just deform and eventually break the bag. Seriously it wouldn't have reached even 95% atmospheric pressure. It's just that you twisted the gallium and so broke through the thin oxide layer and kinda melted small sites together with the heat from friction.
3) When you want to demonstrate cold welding, you need to have a mirror finish on the two joining sides to have any chance to show it. Even slight invisible surface roughness would cause the contact area to be really tiny.
4) If you want a good experiment, get two aluminium blocks that have been lapped to a mirror finish on one side. Take these blocks and your pressure tank, and then using 10,000 grit lapping stones and a buffing cloth, remove the oxide layer. Do this all under argon or CO2, not under vacuum (even 0.05ATM is still billions of oxygen molecules). Just make a rubber layer top with gloves embedded, like you see in hazardous material stations.
The laws of physics on earth: *exist*
A vaccum chamber: "im gonna pretend i didnt see that"
bleh
Other way round.
Laws of physics exists
Earths atmosphere and chemistry:I'm gonna pretend I didn't see that
Are you sure the gallium didn't melt a little and bond that way?
Melting point 85°F room temperature 60°F
Cold welding
His nose : Feels cold let's swell
You need some sort of acid (perhaps ammonia) to first etch away the oxide layer while inside the vacuum, then stick them together. to really get the ingots to fuse.
Im gonna be real honest here and make this comment without fact checking fist. Im pretty sire ammonia is a base, not an acid. But regardless, what i think you are trying to get at is the surface needs to be cleaned before trying this. Whether its removing the oxide layer or just foerign material, the surface needs to. E clean for this to work.
@@metamorphicorder You're absolutely right. I said acid, really meaning surfactant, or something of that nature. I quickly googled magnesium oxide etch, and ammonia was one of the first things that popped up, although there were more, and I just went with that because it seemed reasonably safe enough...
Sir can you make liquid metallic hydrogen in your lab.
Do you know what conditions required to make " liquid metallic hydrogen in lab"
Whaaaaaaat!!!!!!!
Sure, let me replicate jupiter's core like presure conditions in my garage.
That was never going to work, you need to vacuum seal 2 metals of the same type and then while in the chamber remove the oxide layer using some sand paper then when you touch them together they will instantly fuse!
This. I have heard of hatches on space stations being welded shut because the oxide layer on the hinges was scraped away by repeated use.
Hey, gallium has a melting point just above room temperature so when you put it in a vacuum, its melting point becomes low and it just sticks to itself! No cold welding today!
Get some engineering slips. They're so perfectly smooth that putting them together essentially creates a vacuum between them and they stick together like magnets, but they're not magnetic.
It's called ringing when you get to pieces of like material to stick together we use this method in qc labs to put gage block together.
i think it's wringing
The fact that it didn't work the first time shows us how genuine your channel is.
Are you sure this is cold welding and not friction welding? When you put them in the bag and the bag squeezes them, you could have a little bit of friction that could raise the tiny contact points above 85deg. You should put them in the freezer for a while and then try again.
First
Ugh
he is more informative than my school teachers
Damn true
hahaha
That a good looking pickle ngl.
HEh iSs MoR3 inForMatiVE tHaN MY SchO0l tEAchEr$
He makes a lot more money than a teacher
Counting down to the start of the vacuum chamber fan is anti-climactic because the vacuum is yet to be achieved. It's premature evacuation!!!
I just love this Channel
I'm a fan of Physics
It's very interesting!
Physics is fun until you have to do an exam... school ruins everything
@@LucasTheBotIt depends on the teacher if the exams are fun or not
Might be in physics, that you get a lot of joy, when you have to calculate how many photons will come out a green laser every second with 3000 W.
@@LucasTheBot
Concept wise Physics is Fun
But yes I agree with you, exam wise it can get bad a lot of times
But as far as you understand the depths of the vast knowledge that Physics provides you, those tests should not matter.
Just that fun of learning is more than enough!!
That's my take.
What say??
you should check out fermilab @atharva joshi, because physics is everything
I have a little concern about how you performed the experiment in the bag. You performed a twisting motion, which should generate some friction, potentially causing a small amount of liquid Ga to be produced, and then resolidify the two pieces together. Might be something to consider.
This guy said “together” too many times than is scientifically possible in a 10 minute video.
As a welder, I am a bit familiar with cold welding. The presence of oxygen has a near immediate effect on metals that have been grounded smooth.
Too small to see with the naked eye, oxide and rust immediately forms on a cleaned metal surface on a microscopic level.
But if you were to clean the surfaces of two similar metals in an oxygen free tank, they would definitely stick together. I've seen the experiment first hand with a tank filled with pure nitrogen and sealed rubber gloves protruding into the container.
this is so cool no..this is AWESOME
Lolf unny pun
If you had two aluminum plates in your vaccum chamber separated by outward facing sandpaper, and pushed together. Then if you pulled the sandpaper off, thus removing the aluminum oxide, would the two aluminum plates become cold welded?
Not sure if just that limited application of sandpaper would remove enough of the oxide -- if all the oxide-free surface is in grooves, surrounded by ridges of oxide, you still won't be able to get the metal together. You would have to do a more extensive sanding, and somehow do it in vacuum (like be in a spacesuit in a giant vacuum chamber), because if you do it in air, by the time you can get the pieces into the vacuum chamber and draw the air out, the oxide will already be back.
Eye protection when playing with strong magnets. Shatter danger.
My mans have 2 mil subs but gets a average of 75k views like what⁉️⁉️⁉️⁉️
He is the only man who build his career from a vacuum chamber
Doesn't a vacuum make the boiling point drop? And by association, the melting point? So technically, isn't putting gallium in a vacuum, the same as just melting the two halves together?
Feedback requested.
There's another kind of very unique welding done with explosives.
Under extreme heat and pressure you can weld two dissimilar metals making a custom alloy to better suit your needs such as aircraft skin for example.
Friction stir welding also does that, but you can't use it for deep (beyond 1 inch) welds without a special machine.
What about the oxide that formed from being exposed to the air earlier? And if it doesn’t like to form oxides then why is a vacuum required now?
This video sucks, there's a ton of flaws with his experiment. He didn't cold weld at all, the gallium literally just melted a little bit from friction. He mentions the oxide layer in the beginning and how it prevents cold welding, but then completely disregarded for his experiment. Also he seems like he just kinda shat out this video.
Galling is one of the reasons we don't typically use stainless steel anchors for pool safety covers. They are made from brass since they resist galling and oxidize to a nice dark finish that compliments most deckings.
I am from indian and my name is ojas and i am of 13 years but has interest in science and i always see this man all videos how he explains that is the best thing of him he explains very clearly
Why did you need to mention your nationality, name and age?
@@vinaythakur4742 I agree
Damn oxides.. being a welder, I know these things.
This is gallium, which has a low melting point. How are you sure that the warmth from your hand plus the warmth generated by friction of rotating them together didn't cause the interface between the pucks to melt together?
I like these videos a bit more than the ultra black paint kind.
Keep it up!
How did you send this 27 mins ogo the video was made 9 mins ago
@@claudiavanvalkenhoef9971 physics do not work in a vaccum chamber :)
Martin James Who asked you?
I'm pretty sure this was just the vacuum of the two concave hollows suction cupping together.... not cold welded.
Ya know, I really didn't expect that you can weld using coldness. It's so _cool_
theres a similar thing with ice (ik its not metal) but its kinda the same thing
you push 2 pieces of ice together and they get stuck
@@nuiob1766 that's pretty cool
That's due to a pretty different phenomenon dude
Its not USING coldness.
@@melody3741 Yeah I know, trying to make a pun 6 months ago and I don't even know wtf I was trying to say lol
Oh so you used gallium eh? Well now you can’t prove you cold welded them as gallium can melt and so weld itself together at room temperature so this invalidated your results
5:12 "it didn't stick :("
There's another cool video of cold welding by our very own *Cody's Lab!!!* :D
ruclips.net/video/GtcuURSYgvo/видео.html
I was about to look for cold welding on youtube, lucky enough TheActionLab uploads
Day=Made!
If your using stainless steel fasteners, and you don't use some oil or similar on them, you will learn about galling pretty quickly.
“They finally found out it was a series of unfortunate events”, is there anything Count Olaf won’t do!
He is very dedicated XD
NASA: "We never thought about testing it in a vacuum like the big space for which we create work for, chief. Is it time for another billions dollar grant now?"
Every US president: "That's fine."
7:22
Celsius or Fahrenheit
clearly Fahrenheit. Or do you think 60°C (140°F) are normal house temp?
@@neutronenstern.
It is in my house
@@Banana_Judge good radiator
or do you have a very good wood stove or something. Where can i buy it?
Melting point of galium is 29.76 celsius or 85 fahrenheit. So he misspoke.
@@neutronenstern.
No. I live on the sun
So what happen to Galileo Antena ? ... Did NASA weld the Titanium Materials with wrapped plastic in Space ? ... I guess not, because the picture at 1:55 is a CGI ... Same Old Cartoon Story ... :p
Cold welding also works with hard metals, if they have perfectly plane surface and you slide them above each other. Distance or mass calibration items are well suited for this. Such items are stored in a fluid to prevent this from accidentally happening.
Basically a shop grease, filtered kerosene, WD40 but generally you want a rust preventative that is easy to remove so kerosene and WD40 work very well.
As soon got the melting point wrong for gallium i stopped watching 29.76°C
Your room temperature is warm enough to friction spot weld.
Your experiment is flawed!
Stainless steel nuts and bolts will gall especially when using nylock nuts.
Stainless steel pipe fittings are really bad for it, to the point if you dont uses something like graphite in the thread you may never separate them
Gallium melts if a little heat is applied, the friction you created by rotating the 2 pieces caused the round lids to stick together, hence the reason why you could easily pull them apart... nice try tho
James, your genuine excitement over the things you discover in your videos is infectious. Thanks for the killer content!
2:35 and hence the action lab learnt from NASA's mistakes and quickly bought a vacuum chamber :)
3:17 - HOLY SHIT
7:20 "85 degrees Celsius, it's around 60 degrees in here, so..."
Wait a minute.
I remember learning about cold welding in space as a kid, it was so mind blowing, one of many reasons why space it's cool figuratively and literally
You went to space as a kid? That's amazing.
@@Chris.Pontius hahahaha nice bro you make my day
@@FIRE_STORMFOX-3692 danger, Will Robinson!
Your hand oils and dirt are all over the metal... clean them then do this under sanitized clean room environment.
Wait wait wait, so is this considered... cold fusion 😂
Bruh...isn't gallium radioactive and you are touching it with bare hands lol
Is there any chance the friction melted the metal a tiny amount on the surface?
Yes but I am not good at explaining things so I’ll have to look it up but it’s something called “sublime” I think
Not really the friction but yeah friction could help it occur
Sublimation means turning directly from solid to gas, with no liquid stage - such as ice evaporating in temperatures too low for water, or dry ice making clouds. Not related.
@@VoltisArt yes
I think first you have to scrape our the oxide layer first to make them stick well!
Your hair looks great bro❤
Can u explain how plasma channel levitated aluminum in there hand
Would cold welding work in an inert atmosphere like pure nitrogen or argon? Personally, unless I'm missing something crucial, I don't see why not
Surface layer of metals must be kept clean from any impurities
Inertgas is gonna keep metals safe from oxide layer . Since every materials have surface roughness and can act as an air pocket ( impurity ) causing Less metal to metal surface contact . Resulting in very awful weld .
I'm not sure I'd call the gallium sticking as cold welding. You're applying mechanical force and friction, which can easily melt small quantities of the gallium at the interface.
the idea of cold welding is, that only little energy is enough to reduce the oxide layer. no metal is actually "cold".
you have to find a way to remove the oxide layer in a vacuum then find a way to place the two clean surfaces together without ever breaking the vacuum.
Doesn't the friction create heat when you twist it? Just saying 🤷♂️
Yesterday I was playing around with slip gauges and my friend rubbed it together and to my surprise it sticked to each other I thought it was magnetic but today after seeing your video I found it was a more interesting phenomenon.
I worked in Q.A. in manufacturing for years. We used to "wring" gauge blocks together. The phenomena is not entirely understood, but "cold welding" is thought to be in play. Galling: We press fit steel parts together and with certain product designs we'd get galling, and it took a lot of small process changes to eliminate it.
At last.... Oxygen was the Impostor 😶
It definitely helps if you have two flat highly polished surfaces that you put together.
In large steel structures like bridges we often use Tension Friction connections. The mating surfaces are brushed free of rust and the bolts are tightened to snug tight plus 3/4 turn. This creates a kind of pressure weld between the mating surfaces that is stronger than the sheer strength of the bolts. They don’t continue to stick after the bolts are removed.
Didn't you used to have a vacuum box with gloves installed in it?
in a tub full of cold CO2 use sand paper to remove the oxide layer from piece s of aluminum and then see if they will cold weld
Underrated comment! Why would the oxide layer disappear just because you are pulling a vacuum on the aluminium pieces?
I have a question when you talked about galling and cold welding. What about the effect when you put 2 high-precision flat surfaces together and they bond, such as gauge blocks? I remember hearing that I shouldn't leave gauge blocks rung together for long periods of time, else they won't come apart.
I wondered about that too - I think they call it "ringing".
I love all ur vdos
you are lowering the pressure inside the rim, this is how when you expose it to atmospheric pressure, it sticks together
Yeah I'm not convinced this was a real example of cold welding either. I also found the choice of gallium pretty odd
I was hoping you were going to do something like run the two pieces of Gallium over some fine grit sand paper to make their surfaces more uniformly flat, then see how well they stick together. In other words: sand paper on flat table, and gallium face rubbed on the sand paper so it flattens the face. Also, maybe use a solvent to remove any skin oils or other contaminants. But, if you get it too flat, be careful NOT to touch it, unless you have some sort of memory editing technology!!
7:18 see, this is the problem with having multiple measurement units. lets just all agree on one measurment unit system to avoid confusion
For fairness, we should switch to Rankine, the temperature scale nobody uses.
Battlesheep what is 50 rankine like
Would the same be true for the pages in a book?
Groves in those metallic pisces plus vacuum 😂
Was studying friction and came across the term cold wielding and meanwhile I noticed this mans video....
Beautiful .... sensation of the Practical Physics ❤️❤️❤️ dopomin running through my brain