Can You Bounce A Bubble Off a Laser?
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- čas přidán 26. 08. 2020
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Check out Seb's video here: • Laser bubble bounce, w...
Check out Igor's video here: • 🌑 УНИКАЛЬНЫЙ ЭКСПЕРИМЕ...
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This video was the result of me not wanting to trust my intuition about the above video from Igor. My first thought was that it was fake but I wanted to know for sure!
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Pinned 7hrs ago...how curious.
I don't get it
get styropyro, he has a i think 200+ watt laser
Am I crazy or are the speeding up while going through?
@Sandcastle • I'm talking about the aeroplane quote numbnuts
Tom Scott: "Will this burn me?"
Laser expert: "yes definitely"
Tom Scott: *puts his hand in front of it*
Good to hear Tom Scott has at least a little of the chaotic stupid instinct
Didnt you see when he tried to erase his fingerprints?
@Cryonic Family ?? What
I mean, Tom also made a video with Micheal Reeves and William Osman. Kinds speaks to the chaotic energy level lmao
@Cryonic Family im sure that information is somehow related to what i wrote, but i dont see the relation
@@ronwesilen4536 They are spamming that in random message chains. Just ignore them.
My favorite is when someone says in a video "Don't try this at home!" but it's using multi-thousand dollar pieces of equipment. :-P
They're trying to stop Styropyro
They said that too before they turned on the large hadron collider, just in case.
Like the hydraulic press channel
I built a 5W 445nm laser for about $500 and some elbow grease. Doesn’t really take that much to make stupid high power lasers these days now that diodes are so cheap.
@@andrewesther4705 Ah yes, because everyone has both the $500 to blow and the know how to tinker their way into powerful lasers. :-P
The bait with the bubbles bouncing off in the beginning can’t believe y’all lied to me.
I am so disappoint
Was waiting for it the whole video, but as further as the video got, only understood it wasnt going to happen
Thank you
Omfg tysm for this comment
Some people: "This is my boyfried"
Other: "This is my girlfriend"
Steve: "This is my laser-friend"
Gay lazer man
@@panzerofthelake506 gay laser or gay man?
@@JoeySchmidt74 yes
I'm going to refer to any future partners as laser-friends.
@@panzerofthelake506 Pretty sure he has a wife, so bi at the very most to be fair.
My initial reaction was actually laser tweezers, a physics concept where you can suspend a small sphere of a particular snell ratio using a laser, the refraction causes it to impart momentum
Yeah sure, but that is at a very small scale. Though Light technically produces a force: light sails exist (for space) but it has to have very low mass and high surface area, even then the acceleration is still very low.
@@MCSteve_ actually those two affects have different physical causes to my understanding
@@xxportalxx. Yeah you are correct, I should have made that more obvious.
@@MCSteve_ eh it's all just pedantics after all
This is such a civil discussion for a youtube comment section
Tom Scott: "Will this burn me?"
Laser expert: "yes definitely"
Tom Scott: puts his hand in front of it
A true scientist
Trust bet verify
He's not a scientist.
@@hemiacetal1331 He was testing a hypothesis, that absolutely makes him a scientist. I guess
Definitely just a fishing wire tied to the pointer which is hidden by the beam.
yup, that's what I figured as well... time to go check though!
Yes you are right, czcams.com/video/tjAZbo0jb8Q/video.html
@Cryonic Family go to another video and bother someone else, and stop liking your own comment
String theory
reel or fake?
Do not try this at home. These cheap "5mW" (actually ~50mW) laser pointers from eBay can permanently blind you when they reflect off a bubble.
Tricked us at the beginning with the footage...I was waiting for the sudden revelation. Great piece of experimental science to match your more theoretical stuff, I loved the video. Continues to be one of the still most underrated content creators on CZcams.
I notice some people pronounce "t" in "often". It is so weird to me.
Underrated? He has almost a million subs, and his videos get even more views. That’s not what underrated means.
@@biggayhomofag it can mean that, underrated just means "rated under it's actual value", something with an incredibly high value can be regarded as incredible and still be underrated, you can have 10 million subs and be considered underrated
You need to see the companion video to understand the footage.
I love the chemistry between these two. We need more videos of them together!
Are you talking about the lasers and bubbles lol
I think it's more like physics 🤣
Lol he hearted the comment so he must be gay...
@@jjhack3r chemistry doesn't necessarily mean romantics. Two friends have great chemistry. Two actors can have great on-screen chemistry.
“I got a 30watt laser...”
Styropyro “psfffttt, hold my photons!”
I'm imagining a laser show through a cloud of bubbles - how absolutely awesome would that be!
*Title: "Can you bounce a bubble off a laser?"*
*Me: watches first 3 seconds*
*"Yep, it can. No need to watch further"*
Hey you watch Steve Mould too? Do all the cool science CZcamsrs watch each other?!
For those who actually believed the starting clip: it's fake
You obviously didnt watch until the end
Wow, you're so efficient you got the wrong answer. I want to see you insist this works and then attempt it at a party one day.
Lmao at all these replies from ppl who can't take a joke 🤣
"We're all outside an aeroplane now and it's not that cold"
czcams.com/video/C91gKuxutTU/video.html
mathsgear.co.uk/products/its-not-that-cold-t-shirt
you must be Canadian to be affected by this. Sorry John, you ain't true Canadian
But it is still 3 times colder than inside.
cheers mate, had no idea what his shirt said.
For anyone new wondering: It's from a stand-up routine of his where he talks about "bad science", and in that case a book about "facts"; one of them was "The temperature outside of an airplane is six times colder than in a freezer"
The high power laser internal reflections in the bubbles reminded me a lot of how double/triple rainbows work. Might be worth revisiting this from that direction because you can actually see the angles at which light is able to make its way back out of the bubble. That was pretty rad.
I'm imagining a scenario where while you were focusing on the bubbles in the laser, the laser scorched a hole into the wall.
Yup - Done that! My living room wall has a few burn holes on it.
That's why they pointed it at the brick.
The way his laptop is set on the floor in the first bit brings me incredible amounts of anxiety.
I need a laser friend
We all need a laser friend....
I got a Lazer cutting uncle, it has advantages.
I need a friend
Don't we all
That was the immediate takeaway from this video
I just stumbled upon your channel yesterday, it is incredible, it is a gem, I'm out of adjectives, I just love it. Keep it up!
I like how they changed the subreddit name to blackmagicflippery.
Looks like a creatively well-lit string, or string-like materials, are held taunt between two spots and then maneuvered to create an effect.
That is my guess. Like a really low test fishing line tied to the laser and a spot on the wall then held taught.
The Sun is a deadly lazer
*NoT aNyMoRe, ThErE's A bLaNkET*
No it's not
@liltonyabc It’s from the video “The History of the Entire World, I Guess” by Bill Wurst on CZcams
Now the animals can go on land
and they died in a tornado
@@liltonyabc *woosh*
Gotta say the most amazing thing was hearing the guy talking about the actual death ray he is planning to use to make a light show
9:35 look at this still frame and tell me that isn't PEAK Dad energy.
people at home remember to get yourself some laser protection glasses if you are going to try this 0:54
So if you brought a bubble blowing kit as a spy you could easily detect all the hidden lasers
Edit: Ack! I didn't actually watch the full video before commenting I thought it would work! Say goodbye to my spy days, I'd die in 20 seconds
You'll still detect them. It'll just be the blinding reflected laser light that tips you off rather than the bouncing bubbles. ;)
@Cryonic Family ?? Why are you commenting this repeatedly
@@yeetusfetus8687 i had this same thought.. it confused me to heck
technically still not wrong because they would make reflections and refractions
You would've technically been right if you had said hairspray or baby powder!
Your so great at making videos. I love all the fun topics and explanations you provide. I'm in school for the course electromechanical technician. I share your videos all the time.
You know, I thought about how solar sails on certain spacecraft work and thought it might be doing something like that and so I sort of disappointed myself when it didn't work haha! Great video though! 👍
Dang, I was thinking of exactly the same thing.
In this video's title "Can You Bounce A Bubble Off a Laser?" why is the first A capital, but not the second?
You will get the answer in Seb's revelation video!
Love this one, great duo! Thanks!
Love it more now I see you as the Detectorists guys 😊
Hidden gem of a show!
I hope you two are the best of friends. I loved your discourses, really enjoyed this video
6:35 "Don't try this at home". Exactly my thoughts. I have persistent floaties in my vision from unprotected laser exposure in a lab at college years ago. That was a controlled environment where the laser path was protected and controlled, but my lab partner briefly fired laser while my protective glasses were off, and the black curtain that was intended to absorb the laser was down, and I caught some specula reflections off the wall. Watching these laser beams all around the room uncontrolled makes me panic a little bit.
have you tried any treatment for your floaties? i have one too, and rather noticable because it has dark color. i think it was also because i looked into laser keychain directly for long period when i was younger :(
i sometimes work with lasers professionally at my second job and the highest i've ever encountered was 10w and it's crazy seeing ones even above that. but to be honest, when i first saw the video at the beginning i really thought it could be real
You can now buy a single chip with 100w *output* for 300 bucks.
rating lasers in Watts is always a bit misleading. I work with pulse laser systems that are technically 1 W, but because they are nanosecond pulses it corresponds to 100 Megawatts during the actual irradiation. And that's still pretty low by laser standards, the really cutting edge high powered lasers are now operating on the Petawatt scale.
@@Neokretai i was talking about "consumer grade" lasershows and stuff, not industrial lasers. those are usually not pulsed but turned on continuously ^^
9:47 what if you would put some food colouring in the water for your bubble, and maybe absorbs a bit more light. My hypothesis is that heating one spot will cause the pressure to increase in that specific area. Whether it will bounce off the laser or even stick to it could be found out through experimenting. Crank up the amount of different colours of food colouring as you go. Hopefully this effect will be noticeable before the bubble pops. Great video man! Nice collaboration
Next vid: Steve and his laser friend on LSD testings soap bubbles.
"Whoa, look at the colours!"
😮
Damn, you really got me there in the beginning
my intuition was that it could work for some reasons, if the laser was strong enough:
1. The photons of the beam could transfer an impact on the bubble if absorbed or reflected
2. The light could heat the bubble up which would cause it to go up again because of bojency
3. The laser could heat the bubbles downside up, causing it to vaporize and this vaporized water might be able to push the bubble up, also.
Now to calculate how strong the laser had to be to move the bubble with its impact:
P=m*V=5*10^-6Kg*0.01m/s=5*10^-8Ns
The impact should be transferred in 0.01seconds
P=h/l=6.626*10^-34Js/500*10^-9m=1.3*10^-27Ns
If one percent of the light hitting the bubble is reflected or absorbed, transferring its full impact to the bubble, then the impact of the 0.01 seconds long photostorm should have an impact of 5*10^-6Ns
5*10^-6Ns/1.3*10^-27Ns=3.8*10^21 (Photons)
These Photons would have an Energy of
E=N*h*c/l=3.8*10^21*6.626*10^-34Js*3*10^8m/s/500*10^-9m=1511J
So the laser would have to have a power of P=E/t=1511J/0.01s=151100W
This is the power, the laser would need to push a 5*10^-6 Kg bubble with a speed of 1cm/s
It seems at that energy the water would vaporise explosively and cause a small pressure wave which breaks the surface tension and pops the bubble.
If you had a near 100% reflective surface, or reflective enough that at the duration of the pulse and the given energy level it won't vaporise the material, it would work.
It works for the same reason why solar sails work, doesn't it.
@@CaelanStewartThePhpGuy yes what i didnt calculate with is, that the impact change of the bubble is double as high, if the light gets reflected, as it is, when the light gets absorbed. That is, because of in the case of a reflection the photon has got -P after the reflection , what ends in a delta P of 2P (P-(-)P=2P)
Except that none of this works or matters because the bubble is transparent.
Now, if you put some dye in the water you were using, it might very well work indeed.
@@Hallowed_Ground not fully transparent. In the vid you could see, that it was also reflected in some way.Also you can see that a bubble is shimming red yellow ... . So because of intefferation (some light is reflected at the inside of the bubblelayer and some of it at the outside of the bubble layer and if the thickness is some (k+0.5)*k*Lamda it is destructive inteferrence. ) So this causes the photon to be absorbed. So there is indeed some kind of reflection and absorbption.
@@Hallowed_Ground It is not 100% transparent. That means that there is always some quantity reflected, and some absorbed. It's why you can see the bubble at all.
Heck yeah, I met Seb at Smashing Conf. Really cool fella and had a sweet live-coding talk. I love to see two creators I enjoy collaborating.
Also thanks Steve for all the fizzy brain feelings you've provided 😁
I think you could get it to work: with colour in the bubble (maybe from coloured soap) and a laser in a color that gets absorbed by the pigments in the bubble.
Part of the contract is always: No air quotes around "laser" ;)
It's Mulder ("I Want To Believe") versus Scully in Steve's brain!
Thank you for the footage, it is so pretty!
Good to know! Our future battleships will have bubble generators to distort incoming lasers. Thank you for saving us from future alien invasions.
This was pretty fun. Good work.
PLEASE do a video about the clicking sound that lasers make, I would love to see a video from you about the photoacoustic effect!
It's super fascinating and I know you would do it justice.
"The photoacoustic effect or optoacoustic effect is the formation of sound waves following light absorption in a material sample. In order to obtain this effect the light intensity must vary, either periodically (modulated light) or as a single flash (pulsed light)."
9:09 You know you have to explain those now, Steve :p
they had a glitter ball just above where the bubble was.
@@benjaminq3226 A glitter ball? What? Can you explain what you mean?
It seems maybe the reflected light is bouncing off something but considering the reflective light is a total blur of colours I don't understand how that happened?
Those are caused by constructive and destructive interference.
5:37I was surprised that you didn't embark on another project even though you saw the fantastic reflections on the ground. I've always been fascinated by the surface of bubbles and those reflections on the ground could have given you a good opportunity to study them.
This video taught me that the visual effects lasers used for concerts are terrifyingly powerful. I have a 5.5W diode laser that I use for laser cutting and engraving and it burns through 3mm plywood in less than a second when at the focal point. Seb said he's going to do a project with a 30W laser which is up into the CO2 laser power range which are used for industrial laser cutting of thick wood and plastic.
Just as a piece of logic in the intro: “If it pops it was never going to bounce”. Not necessarily true. There is an effect with molten metal where you can briefly dip finger (obvious hazards here.... if you try and it goes wrong... it’s on you). Modest temps don’t give a protective vapour layer and burn, higher temps can work. Not all effects are linear.
However, in this case, my intuition matched yours, I’m just being pedantic.
The Leidenfrost effect, where a high thermal differential creates an insulating vapor barrier between hot and cold surfaces. You can also see the effect in action by placing drops of water onto the surface of a very hot griddle and watching them skitter about on a cushion of vapor. It's definitely a much safer demonstration, though not as badass as dipping your hand in molten metal.
You had some rather serious secondary emissions going on there.
When I saw the rainbow colors reflected onto the floor I was confused, "lasers are monochromatic, wtf is going in here!?". I think the laser they were using has multiple laser sources inside and combines them into a single beam. So probably not secondary emissions, rather, 3 primary emissions.
@@dennisdavis6943 The bubble is Refracting the Light. Shifting the Wave Length.
I was thinking they proved light has mass.
@@pulesjet yeah, I should have said "refracted onto the floor". But still, lasers are (mostly) monochromatic, so refraction won't create a rainbow like full spectrum white light would
Refraction does not shift the wavelength
@@dennisdavis6943 Sure it can. The refraction bending the wave would generate shifted light
The multi colors are because of the varying thickness of the bubble cell. I don't think it would be vary prominent using Red light. The shift being none linear ..
I absolutely love these kind of videos.
I love that you don't put things like this away because they seem not logic. Most thing's we still don't know, so getting into it is not to blame even if it doesn't make sense. Knowing it's fake is education too and to proove it's fake, helps against people who will say:" did you know lasers can bounce a bubble" "I saw it". Also people will remind more, that not to trust everything only because it's a popular video... ! Great impressions and wonderfull color play. Greetings from germany
And here I am with a 150w CO2 laser I bought from china just chillin' in the other room like it's nbd. It's a 7ft water cooled glass tube.
I wish I had a laser friend.
My speculation regarding the bouncing effect toward the end is that there is a very thin colorless wire (like fishing line) connected to the laser to the wall, and it's actually the line that bounce the bubble. This is because the position that they are pointing the laser at seem to be a fixed position on the wall, which is where the wire is mounted. There are some weird glaring effect when they move it around even without hitting the bubble (around 10:33), which is the effect of laser diffracting though the transparent wire (while dust can have similar effect, it just seems a bit unnatural).
By the way, I haven't watch the other video yet, and this is only my speculation.
in theory, it's possible to use a laser to move transparent particles. But they need to be much smaller and lighter than a bubble of water, and they need to have a high enough refractive index (which bubbles don't have, because they contain mostly air).
the way the laser bounces in the particle can create a force strong enough to move it and prevent it from escaping the laser.
It's calles an "optical trap" and there are scientific papers about it.
You can’t just put a “WTF” in the middle of the video and then not talk about it
Explained in Seb's video :)
Steve Mould God, I laughed so hard when he explained it. I love it when I find genuinely scientifically curious people. Sometimes it’s just a joke or a disco ball, but what’s the fun in that right?
Haha, I love that the answer to the WTF diffraction pattern thing was just a disco ball! czcams.com/video/tjAZbo0jb8Q/video.html
It was?
@@jskullheisenberg5227 Yeah, they reveal it in Seb's video czcams.com/video/tjAZbo0jb8Q/video.html
How much does the bubble weigh? What is its pressure on the beam? How large is the beam and what is the power density?
The energy density for the beam is (powerdensity Watts/m2)/(velocity m/s)
The pressure on the beam is mg/A where A is the area of contact.
Yes the beam power varies with distance from the center of the beam. Yes, if the beam has frequencies that match absorption in the components of air it will heat the air. But if the bubble is too heavy, it won't bounce. The laser will heat the bubble if the spectrum of the laser includes absorption in the bubble materials.
If you use a steady stream of air to form the bubbles - blow through a tube or inject fixed volume of air - it is easier to quantify the size of the bubble. If the air to blow the bubble is much warmer than the air around you get to play with balloon buoyancy.
Put all that in a spreadsheet and keep adjusting for likely places where the conditions match, and you have a better chance to reproduce that earlier video. You can model most all the variables and gather them together. No matter how many pieces you can think of. Put them into quantitative form. Measure as many things as you can - the videos are quantifiable. They give you things like size, estimated mass, surface tension (the "give" when you move the bubble), velocity and acceleration. If you try to do this all in your head the time it will take you is a long time. Unless you have already spent years playing with bubbles.
en.wikipedia.org/wiki/Photon and jump down to 'spin angular momentum'. Just above that it say momentum (p) is PlancksConstant (h) divided by the wavelength. That is kg*meter/second
Go to en.wikipedia.org/wiki/Radiation_pressure#Radiation_pressure_from_momentum_of_an_electromagnetic_wave and see that the radiation pressure is just the "irradiance" (Watts/meter2) or power density (Watts/meter2). I just say (Watts/Meter^2) and don't care what the name is.
So that cos^2(angle) just below is for grazing incidence. Then it is vectors for working out the forces. These are macroscopic things you can measure.
When I face a new and complicated problem (magnetic levitation, magnet motors, formation of clouds, gravitational sensors, whatever) I focus on the units that people are using, I memorize the names and write them down. I keep track of all the links because sure as shoot'in you will have to go back again or want to tell someone.
Without measuring anything, this bouncing bubble thing could take a long time to get right.
I wonder if you can see the laser bend the surface of the bubble?
The use of lasers to move things around has engaged many tens of thousands of people. It is important in many fields and growing in sophistication and value. Take a look at "Optical tweezers" on google. There are 984,000 entry points for that exact phrase (if google is not fudging their numbers).
en.wikipedia.org/wiki/Optical_tweezers is much harder than it needs to be. Those equations are all images so you can't even copy them into a decent symbolic math program to use them. Not a single calculator on the page. But search for "typical photon radiation pressure" and then read "counters the downward force of gravity". So if you start measuring the waist size of the beam, or learning how to measure the beam power profile or the detailed spectrum (any light will do, any mixture of light will do, just do the numbers)
On the Internet as a whole every tiny piece of science, technology, math and all knowledge is massively duplicated, repeated without links and supporting information and tools. I have been studying the growth and diffusion of topics and methods on the Internet every day for the last 23 years. I like what the Internet could become, but right not all I can say is that it is a sad mess. Here as I read there are 361,990 views of this 13 minute video. If everyone only watch half, that is 39,215.6 hours of human time spent. The value of human time that I use for estimating on the Internet is $32 per hour. So the time spent on this video is roughly $1.25 Million worth of human time. And if all the people who watch were serious about wanting to know, then perhaps it should be worth that much to find a decent answer. Some of the people on CZcams who ask for support invest in learning and measuring. Some very popular ones just stay at entertainment and wonder.
Richard Collins, Director, The Internet Foundation
The bit with you two at the end was wonderful
If I may, You should Colab with styropyro for anything related to laser or electricity in general.
Adil Nadaf 🤜🏿⚡️🤛🏼
my first thought of that video that was sent to you was that that guy should 100% be wearing laser safety goggles. my second thought was that maaaaybe it was a high enough power to heat up the bubble and get it to rise or something to that effect...in which case wait, he should 110% be wearing laser safety goggles! or maaaaybe the composition of the bobble and the laser wavelength interacted just right?? probably faked
I haven't watched their explanation yet, but holy f I totally agree with you on the glasses. You can actually see green light refracting onto his face several times and that green laser looks way above 25mW, so serious eye threat territory!
Here hoping to he faked the laser, otherwise this is some serious stupid handling of lasers O.o
before the test, my theory is that the surface is being evaporated and that would be the force to lift it back up
That's what I was hoping for too
You put so much effort into your shows. No wonder your a success. Leaving brain teasers in, just the subtle stuff nothing too overt. No wonder i keep coming back for more. Thinking of how you bounced the bubble off the lazer was an interesting 2 minute brain twister. That was stimulating. ..
Not giving the answers away is just as fun. Heres a clue though. If you look carefully you'll notice that in every one of the shots some of the bubbles were effected by the lazer. Catching hold of it and spinning around it. I bet you guys had to remake that solution a bunch just so that didn't happen lol.
9:08 they almost broke the Matrix
xd
"Don't try this at home!"
-- Nope, just try it at Steve's house.
5:30 Seeing this, I'm going to need bubble machines for my rave
5:30 the reflected colors on the floor are amazing
The WTF pattern can’t be diffraction right? Because different colours show up at the same spot.
They explain it in Sebs video, it's not diffraction
I'll be honest, the conclusion of this video made me mad at you, Steve Mould. I came in here, honestly curious at the question in the video title, but even at the end of it, I'm no closer to an answer. If this was supposed to be a riff on how 'bad science' is done, I failed to clue into it until reading the other comments. if it wasn't, then this is a cheep (in the worst meaning of the word) way to share views between your video and Seb's.
Down voted for, if nothing else, a clickbait title.
You blew my mind more than usual with this one! 😲😲😲
Here's one thing I discovered. If I shine a very bright flashlight (in my case, a Rovyvon Aurora A3) onto a piece of aluminum foil, I would hear a faint humming sound. I tried wrapping the aluminum foil around a piece of metal, then putting it over a flame to deposit a very thin layer of soot, essentially making poor man's VantaBlack. This made the humming significantly louder. The humming would only appear with the flashlight in the low or medium brightness settings, since at full brightness the LED is lit 100% of the time, but a lower brightness levels the led is illuminated using pulse width modulation
Laser dude: imma use dis worlds most powerful 30W laser
*angry styropyro noises*
I was skeptical but i figured that if it *did* happen it would be a phenomenon like water droplets skittering on a hotplate - the laser would vaporize a tiny bit of the bottom of the bubble, which would fire off a tiny bit of steam which would propel the bubble up and away. But on further thought A) that sure seems like it would be more likely to pop the bubble than to do the cool thing we want, and B) there's no way a soap bubble (mostly transparent) would absorb enough energy fast enough from visible light to vaporize anything without *absurd* power densities.
So a "no" answer makes a ton more sense.
Gotta love the guy in the video just standing there without any eye protection as that laser scatters into a clusterf of small laserbeams in his face
One super neat detail is how the bubbles don't have any dust in them. The beam has a slight fuzzy look when going through the air outside the bubble, but the laser beam inside the bubble is perfectly coherent.
I’m a little foolish for mentioning this (because you guys were so definitive). Being MythBuster-minded, I really wanted it to work.
There is a soap bubble artist/performer that uses different recipes depending on the performance or even the humidity of the environment. This wasn’t explored at all in this video.
But u guys were so definitive 😆
Well, hey. If someone could just mention below how a soap bubble’s makeup wouldn’t matter neither, I guess I’d be satisfied 🙂
The fact that a soap bubble is transparent to the frequencies of the laser light means that the light and the bubble do not really interact. If there is very little interaction, there is very little opportunity for the energy of the laser to be transferred to the bubble. As long as the bubble is transparent (no matter what the ingredients are) the laser cannot 'push' on it hard enough.
@@mokopa Thank you for finding my comment 😄. Rewatching and feeling foolish all over again. Solid answer!
remember the dual nature of light. it can behave as both a wave and a particle. perhaps as a particle in can collide with a surface or something. an inelastic collision which results in the sound/clicky sound heard
Great video, you just answered the question in the first 10 seconds love it
While inconclusive experiments or videos where a cool thing didn’t happen, I’m glad you put this up. Just like rigorous scientific studies with mundane studies don’t get published, we need to see more of them to benefit the scientific method. If for example a certain diet or drug is shown by three major studies to be effective, but maybe ten other studies were inconclusive, we might be better informed overall. I know this isn’t how studies work exactly, but with more data from multiple studies, maybe the composite data would be inconclusive also cutting through the noise of confirmation bias.
A bubble COULD, in theory, be pushed by a laser, photons do have momentum, but only would be pushed if said bubble were in a vacuum, say the vacuum of space.
The momentum of a photon of visible light is about 1.47 * 10^-27 KgM/s (this being specific to a certain frequency of green light, around 550nm to 570nm). A bubble is around 160 micrograms and it falls at about 0.495 m/s, giving it a momentum of 7.92×10^-8 KgM/s which is about 5.4 × 10^19 times (54000000000000000000) the momentum of a photon (keep in mind I'm assuming a single photon and a single bubble, a laser has a lot of photons, obviously).
In a vacuum, with enough time, you could noticeably push the bubble with the laser. The bubble, whilst transparent, is not completely so and as such would get affected by the laser.
So yes, you could push a bubble with a laser, but not under an atmosphere, and certainly not within a reasonable time frame.
Remember those floating faucets that would keep pouring water.
Thank you for answering the question at the start of the vid.
It's so funny to me how strong my instinct to look away from things that would IRL be vision hazards even though I know the brightest it can get is no brighter than the white pixels around the video (get this any time I watch a video with a welding arc visible, too)
My first guess was 'maybe if the laser has just the right level of power, it could be ablating the bubble and causing just a tiny bit of thrust', in the same vane that you can use lasers to shove space debris around. Kind of disappointing that even with a stupid-powerful laser, nothing happened still. I can't help but remain curious if there _is_ a sweet spot where a bubble can be gently ablated and pushed around with a laser, but not instantly burst.
Hi Steve, interesting video! Did you consider adding a dye to the bubble liquid, to cause local light absorption and perhaps some convective air current? Or perhaps filling the bubble with something absorbing smoke or iodine gas as the two safest alternatives, not many gases are both coloured and safe to use, unfortunately). Another alternative might be using an infrared laser and exploit the natural absorbance of atmospheric gases. In any of these cases, I would expect the bubble to burst rather than to lift, honestly.
Looks like you used fishing line or "invisible thread" (like the clear plastic stuff) for the effect. In some of the last bounces it seems like the far end of the "beam" lags behind the laser pointer's motion, as though someone is holding the other end trying to mimic his movement. To make the string look like a laser you could have easily just put a light at the far end (or the laser itself if you could line it up well enough) and used it like a fiber-optic line. Cool effect none the less, and of course that's all just a theory.
Maybe wavelength could be important?
Otherwise though I'm looking to make it work, so maybe you could make hot air bubbles by putting a smoke in to make the air inside them heat up? I know it'll expand the bubble but I just hope or wish it would work for a moment.
If only the light could bounce off of the edge while it is still reflecting
Great, now I want to run a pair of projectors, shoot some sheets with them, and cover them with a bubble machine. Would be an even cooler glitter than projecting onto a disco ball!
There was a colourant in the original soap bubble that is hidden by the dark background. The colourant transfers the energy into the bubble instead of allowing the light to pass thru.
Lights beams and bubbles...
Sounds like the perfect way to defeat some ancient aztec body builder
Steve, if this weird pattern (looked like almost like a diffraction grating pattern) at around 9:10 was really from the bubble, then you should definitly look closer into it. You might end up with your second effect named after you. Two things which are weird about the pattern -it was not moving/not connected to any movement of the bubble -the three colores where in the same place, which is not how gratings work. But as I think your brain works, you would have thought already about it. Or it was fake otherwise, if not I order myself a 30 Watt Laser :).
Cheers
Johnny
haha it's funny when I first discovered it in the footage I had already decided it would be the Lee-Delisle effect 😊 We figure out what causes it my counterpart video.
Just some thin transparent fishing line. One end fixed just under the output of the laser, and the other end fixed to a wall outside of the video frame. String should be always tense, hence the strange handling of the laser.
Those strange spots looked a lot like a diffraction pattern. I believe you can diffract a laser pointer with the weave of some fabrics. Perhaps some particulate with the appropriate spacing popped into the beam.
My random wild (and entirely not-thought-through) hypothesis at the start of the video was some sort of leidenfrost-effect-ish thing, where the laser light would get absorbed-enough if it's just skimming the edge of the bubble to rapidly heat the liquid there - somehow enough to cause the tiny-steam leidenfrost thing but not cooking the bubble film enough to pop it.
Steve describing learning like it's the hardest drug with the longest-tailed dragon to chase....
(I kinda love it tbh)
It would be neat to try that with an IR laser. I have a 35W 12.6um laser. If I ever have it running outside of the enclosure for some stupid reason I will have to give the bouncing bubble a shot. I would think it would instantly pop it though as water absorbs IR very well in that wavelength (in the past I have pointed it into a cup of water to have that sink the laser output, and I could get an idea of the power by looking at how far down the water is boiling).
9:03 "yeah it's just doing nothing" as a light show is dancing on the floor and the walls!! haha
My first thought was "why isn't he wearing protective goggles?"
Watching this video after watching Walter Lewin's lecture on the Hidden Beauty of Rainbows and seeing the physics of light reflection within a water droplet (in this case, a soap bubble) being demonstrated in real time is just amazingly cool.