Thanks for watching! I mentioned the wrong Japanese scientist - Mototarô Eguchi was the man. Use code 50PLASMA to get 50% OFF plus free shipping on your first Factor box at bit.ly/4eHXfxx! Also, here are the links to Onshape ( Onshape.pro/PlasmaChannel ) and the custom transformer video: ua-cam.com/video/DkhpuuPljS4/v-deo.html . Let me know what you think about these really cool mysteries called Electrets!
Being able to do that but in reverse would be fantastic, it would have a real application for space suit design too. A space suit that can repel lunar dust via permanent static charge would be a truly useful invention.
@@Alfred-Neuman The difference is that the balloon eventually loses its charge, but this keeps it for a long time. As an analogy: a magnetized nail is to a permanent magnet as the balloon is to an electret
They're used all the time in microphones. They sandwich an electret between two metal plates, the electret vibrates and the capacitance is measured after the signal is amplified by a JFET which is usually included in the actual microphone module. It is a real treat to learn such esoteric knowledge and to see experiments that very few, if any people have ever seen. And just 200 years ago if you lived on a farm all your life, you wouldn't even know what the ocean looks like. It's easy to take things like that for granted. But it's nice to take a moment to think about it.
Set the electret on a fixed stand. Take the detector and move it around behind it on a fixed distance. Now set your camera to a long-exposure and you will get an image of the complete electric field in high resolution..
Even better, put a detector on a gantry that can trace out many points in a circle around the electret, and let the detector feed a microcontroller. Then you can model a digital representation of the field
Similarly, spin the sensor on a lazy Susan to get a far higher resolution image with a faster frame rate, with the same sensor and very little complexity.
A little higher resolution with a little more complexity could be had by spinning the sensor on two parallel axes where one is slightly offset from the other, so the LEDs trace spirograph patterns that cover most of the surface area. With a little clever counterweighting this could be done completely passively (no motors, just hand powered) with two lazy susans.
Diffusers in front of the leds would be easier to see the field and maybe it would work better mounted on a proper pcb instead of free floating solder joints
Dagnabbit. I was going to suggest something similar. Bipolar sensors and dichromatic lights to indicate electric field polarity and intensity simultaneously.
You can use the electret to test the Poynting Vector if you'd like a follow-up video. A moving electret is a current of sorts. It should resist a change in position with a tiny force. A moving charge also generates a far field, a radio field. So, spinning one fast enough should generate a radio wave. (Due to Special Relativity, look for the relevant equations in a Physics book. Breaking Radiation.)
@@PlasmaChannel According to relativity, a magnetic field is just an electrostatic field seen from a different frame of reference, so yes, it should generate a radio wave, but you'd have to spin the thing pretty damn fast to get a decent frequency.
Everytime I start to believe that i know everything in fundamental sciences these very intelligent science youtubers come up with videos about things that are not taught or available mainstream. I love your videos plasma man. I've always used electret microphones in my electronic projects always thought that electret is some trade name or something this video proved me wrong and made me Learn something new. Wonderful! Thanks.
@thekaxmax what undergraduate engineering school has "electrets" in the syllabus? I have a BE in electronics. I think maybe materiel science and engineering but electrets are surely some advanced pg or phd level stuff...
So permanent Realy means permanent? Dosent lose the proprities? This looked like a cool way to do a puzzle for a escape room. Is there anyway I could buy one of these?
Rather than making a 10 by 10 sensor field: Mount your current sensor field on a jig that you can move both horizontally and vertically, either manually or by stepper motors with belts. Then you can mount your electret in front of the sensor field and move the field about while recording the results with a static (non moving in this case) camera on a tripod. That should give you an immense amount of data if you overlay the frames additively. I'd love to see this in action if you have a chance.
Quick note, but when melting wax, candle makers use a bain-marie. A water bath. You fill the pan with water then put another container within, stood up on a couple of blocks. The wax goes in that. That way the temperature can never get above 100C. It's fine for wax (and also chocolate come to think of it), and it won't get high enough that the wax might ignite or char.
If you look at electret papers its actually common to heat the wax above 100C to drive off water. A water bath is typically not used for this reason. Some of the papers I read used a temperature controlled oven for this.
@@carpdog42 I can see that, but when doing it at home on a cooker, there's a fair chance that, if the wax vapourises, it can catch light, particularly if it's a gas cooker. Not just catch light, but explode and send burning bits of wax all over the place. It's dangerous, and a bain marie (AKA double boiler, thanks @thezfunk) is what candle makers use. Perhaps steam might affect the dielectric strength of the wax. In that case it might be good just to have a non-water fire extinguisher ready, because water would do what it does with burning fat in another common way to burn your house down. That is, if a pan of oil or fat catches fire, and you add water, the water sinks underneath, since it's more dense than oil or fat. The water sinks, then immediately heats up and boils, almost instantly, causing steam to fly out everywhere, throwing burning fat all over the place with it. It looks like setting off a pan of petrol, fire brigades will sometimes demonstrate that to the public, you can find video of it. Huge explosion! Starts lots of house fires. So from that point of view maybe use a bain marie. If it buggers up the dielectric, then instead have a non-water fire extinguisher suitable for putting out burning fats or fuels. Usually, I think, that means the powder type.
Makes for a very good filter for the smallest particles doesn't it? I have used a few metallic static charged filters but they lose their charge with time
@@Technichian462 3M bought the technology from a Dutch firm decades ago. It's really interesting how they make charged fibres, but I'm uncertain how much is a trade secret: it's enough to know that once the fibres have been formed into a non-woven fabric that the overall charge is zero (as measured form the outside), and yet individual fibres retain their charge like little capacitors.
@@DarkAttack14 Unlike HEPA filters, which use physical restriction to block particles, Electret fibres actually pull particulates from the airstream. Did you know that the masks used by most folks during the PN-demic were actually useless in thwarting viruses by the way?
For the high-res version, I think you'll have an easier time designing a PCB and having it assembled for you by JLCPCB or PCBWay. You might even be able to have the sponsor the video, I've seen them sponsor quite a few maker videos featuring their PCBs
Beat me to it! MM resolution on the sensors and the whole thing assembled for you. They'd probably do it for free for a sponsor bit, too, which I'm okay with.
These are also used in commercial radon detection systems as well. A small disc electret (with both plates permanently attached) is charged (by the manufacturer) to a known static voltage, sent out to vendors, which take them the locations (to be evaluated for radon) and placed in a reusable chamber with known air volume exposed to its surface. To activate the detector you simply expose opening of the chamber to the location air. After x number of hours (or days) the electrets charge voltage is read out on a handheld device, and the amount of radon it was exposed to is calculated based in the size of the container and the net decrease in the electrets charge voltage. The principal of these systems is Radon's decay products (in the air) will slowly strip the electret of its charge, and can be easily read out with a static detector (in the handheld device). After several exposures the electret will no longer have enough charge for the reader to detect and you will have to send your electrets back to the manufacture for "refurbishment" I think I'm going to try to remelt them (after they are fully discharged from use) and cool under a high voltage source and see if I can find out the range needed to "refurbish" them myself!😁
Are you sure it is an electret? If I understand the concept, like a magnet, once charged, they don't discharge. Otherwise, it would be a capacitor that can be charged and discharged. An electret has the molecules arranged in the body of the material, where it remains, until you melt the material and allow the molecules to discharge, which is why they can have a permanent charge. A device that detects radiation by losing a voltage charge is called a dosimeter, and it works by having the radiation discharge the material over time, and the faster the discharge, the higher the radiation. But it works with materials that are not permanently charged, but are charged before use.
@@MadScientist267 Correct, radon gas is everywhere, and it is worse underground, which is why some people report feeling better underground. Mammoth Caves had a village built underground for some people, and they lived there until they discovered the radon gas phenomena, and the damage it causes, is very bad. Which is why they have radon gas detectors.
The word electret sounded vaguely familiar but I couldn't place it until the last frame when you mentioned microphones. I remember the word from electronics kits and tape recorders when i was a kid back in the 70s and 80s "electret microphone." It was just a word back then. I had no idea what it meant. Interesting video, thanks.
Same here! The first thing that came to my mind when I saw the title was - a microphone. My young self heard from dad that it was "capacitive", as opposed to 'dynamic' that were "inductive" because they were based on a coil and a magnet, just like every single speaker we've had. I remember wondering, if that's possible, then why don't we have capacitive speakers then? Imagine my grin when I understood how piezo-speakers from cheap toys exactly worked :D
Well done Bro. Dielectric Fields are fascinating. I am glad you are into electrets. Thomas Townsend Brown made the best ones his unreleased patents are on the TT Brown Family website. Using Heavy elements like Tungsten Carbonate ans Carnauba Wax making an tuned potential battery
@@AdrianBoyko For example mount the sensor on the head of a 3d printer. If you could move that freely to any position you could take a picture each time and at the end merge them together
"Thumb - Power and influence. Men wearing a ring on their thumb has long been viewed as a symbol of power or influence. It has also been associated with high-class society and royalty."
This is how face mask filter media can be higher filtration efficiency than just the fabric itself. The material is made from polypropylene and is charged between charged bars.
Not just face masks. It is used much more in furnace filters! They are really effective when combined with a box fan. I had a 20 inch box fan and then used 5 furnace filters to create a big whole apartment air filter setup. The downside is 5 high merv furnace filters can cost up to 80 bucks and they only last around 3ish months depending on use time
You just gained a sub. As a science enthusiast, I have never heard of this concept. I'm truly excited to see the practical applications of electrets in action.
Honestly this video was perfectly timed. I was about to put some money down this week and buy what I've learned now the wrong materials to build this exact electret. Thank you so so much for making this video right now. You saved me days and days of work :-)!!
My biggest note would be that as I went over the papers on this subject, some of the more "recent" ones on using wax (1960s I think) talked about how it was safer and more reliable to create the wax disks first, and then electrify them while solid. There is a solid phase change in the carnuba wax somewhere around 70C which is the sweet spot. Also, of note your wax had some large stress fractures, which can be minimized by adding some bees wax and/or cooling more slowly. You really beat me to my own project here, but you also solved a lot of the issues slowing me down. I wasn't confident at using 3d printed materials as a mold due to temperatures involved, and so I designed molds to pour silicone molds. My first attempt failed the same way except since my plates were well insulated the sparking happened right down the side of the solid wax and left tracks down the inside of the mold and on the wax.
I don't know if this will help, but I did a study on why high voltage wires have ribbed insulators. Turns out the ribs increase the length of the path needed for the original contact. Hard to mold ribs in the substance without a four part mold, but I would want to pour that object from the side anyway to make better contact with the plates.
I did indeed learn a lot. I already knew about Electret condenser microphones... I did not know how they differed from regular condenser mics aside from not needing phantom power, but very early in the video I finally understood where they got their names, and why they don't need power :D
Most people think science is for nerds... while using hundreds of modern inventions a day that eould not exist without science... Then they voted for Trump. Most people are pretty freaking stupid and uncurious.
I love the way you show your process, starting with incomplete design and then refining. Helps the viewer understand principals of electricity by first doing things wrong then showing how to do the correctly and why. Discovery method of teaching is very good.
imagine how strong it would be charged if you apply a voltage across thats at 95% of the dielectric breakdown for that thickness. 40kv for PE this thick is nothing. 1 inch would be able to withstand at least half a megavolt. (>19MV/m for solid PE) you could stick two electret discs together with this field strength theres a method of forming lichtenberg figures inside clear acrylic plastic by bombarding it with a electron accelerator to charge it up massively and then ram a grounded spike into it to discharge it in one snap.
What would be the lifting force for something like this? Like how powerfull could we make these if we REALLY tried? Enough to lift a kilogram? Several kilograms?
You'd have to make a big slab of material with the field applied only in the middle, that's the only way to avoid breakdown of the surrounding air. Then cut out the electret bit. But yet, if you build it that way to solve the breakdown problem, you could turn the voltage way, way, way up. But there is a limit: Once you have most of the molecules lined up, no amount of extra voltage will give a stronger electret.
Ya know... since water molecules have a posituve/negative orientation... it would be tricky... but I bet you could make an electret out of ice...? You would have to freeze the water while it was being exposed to the external charge...
@@johnharris5786 also you would probley need to cool the water very quickly so it cant crystalize as during the crystallization the dipoles will align preventing the effect
@@a.kjfhkziujsfdgbskjxfyhgfl2332 Two good points. I guess you would have to work out if the amount of power dissipated by the water is enough to stop cooling in the first place. If the current is small enough it shouldn't matter too much? As to the second point, would it be possible to cool the water down to zero or even sub zero and keep it a liquid by agitating it maybe? You then only need to apply the electric field just before it freezes.
You should try your hand at making a Birkland Eyed generator, making nitric acid from air using a plasma arc. Some designs used magnets or electromagnets to force the arc into a disc, donut shape or others to increase efficiency.
please try this "weird" phenomenon using your electret : When a magnet and an electret are near one another, a rather unusual phenomenon occurs: while stationary, neither has any effect on one another. However, when an electret is moved with respect to a magnetic pole, a force is felt which acts perpendicular to the magnetic field, pushing the electret along a path 90 degrees to the expected direction of "push" as would be felt with another magnet.
When you point your finger at your Van de Graaff generator, it doesn't actually lose charge, or at least not a lot. The static electric field from the generator causes the electrons in your finger to be either attracted on pushed away, depending on charge of the sphere. The result is a charged finger, which creates it's own electric field, which is opposite to the primary field and completely offsets it within your finger. But this field extends beyond your finger, weakening the primary field. If you get your finger close enough to the generator, it's field becomes strong enough to reduce the field at the detector below the detection threshold.
Puzzle for me too. Either that was wireless current to ground (finger lightning rod facilitating cloud discharge) or the space between the battery/antenna plate and the Jay/tesla plate was being made a polarized dielectric (capacitor?), and I'm not sure it's not both.
@@cherylm2C6671 Same, I think. Even a capacitor is a conductor with high dielectric resistance. Sparks/lightning are dielectric breakdown, but there is also less violent transfer of charge, which accumulates gradually. In this case, charge was diverted away from the sensor to his finger. Likely, if the finger was insulated, once it accumulated enough charge, the diversion would cease and the sensor would light up again.
Love all your videos. You are definitely among the youtubers that convinced me to finally get into electronics and I am now working on my first project (as an adult, I took electronics in high school)
In theory any insulating material can demonstrate the phenomenon, however the melting is the key. In the liquid state, the molecules are influenced by the external electric field. As it solidifies, the molecules retain their physical orientation, and so a permanent field. It's very similar to how a permanent magnet is formed... the alloy doesn't need to "melt" but it is heated above its curie point and exposed to a strong external magnetic field as it cools. When it is crystalline again, the grains are all oriented and locked in with the original field, and a permanent magnet is created. It wouldn't make sense for this to not be possible... it would break the idea that magnetism and electric fields are two sides of the same coin.
@@janhemmer8181 Good question, and while I don't know for sure, it likely doesn't affect it much if at all. There's nothing intrinsic to ionized air that should have an effect far as I'm aware. Elevated temperatures and ionizing *radiation* would degrade it however, by causing mechanical/physical effects that disturb the ability of the material to maintain its polarization at the molecular level.
@MadScientist267 My reason for asking is because i know this is what happens with a plastic surface that has been rubbed with a cloth. Hovering above it with a grounded spiked metal rod will instantly transfer ionized air molecules of opposite charge to that surface and cancel the electric field. I cannot see how this case will be any different. The material of course will stay polarized but no outside effect of that polarization will be noticable.
@@janhemmer8181 The key difference is where the charges are in the material. When you rub dissimilar materials together, the charges that are created are held only on the surface of the material(s). In the case of the electret, these charges are trapped within the entire bulk of the material. They aren't able to freely "escape" as they are in a material that has simply been rubbed.
Another idea for mapping the field. Have just one sensor, or a row of them and move the sensors across smoothly while using a long camera exposure. Not sure how well it would work but might be easier than creating a huge grid. A challenge there would be ensuring it moves at a constant speed.
Hmm... if you cut a magnet in half, you'll get 2 magnets - both with north and south poles. However, what happens if you cut an electret in half? Would you have one positively charged and one negatively charged, or will you have 2 with both types of charges?
Not really, electrets can be one single charge. The way this one is made its basically a fixed gradient. You could cut it and put it back together, it won't change when cut apart like magnets do.
They work differently on a fundamental level, so you wouldn't expect the same behaviour. Magnets create two magnets when cut in half because magnetic monopoles don't exist (a magnet is a magnetic dipole). Electric monopoles do exist though, so you it is theoretically possible to cut an electret in half and get two electric monopoles (rather than another electret/dipole).
Yes it would behave similar to a magnet, maintaining a positive and negative pole no matter where you slice it. That is due to the way he is making these. He applies a polarized field while it is cooling leading to polarized molecules lining up along the field. If instead he bombarded a wax or plastic brick with an electron gun, he could in theory create a uniform distribution of excess electrons such that when sliced the two halves would not be polarized but simply uniformly negatively charged.
Yes. The system essentially aligns electric dipoles rather than storing charge. When in liquid form, dielectric dipoles align, and as the material solidifies, the dipoles remain in place. This creates an electric field. When you cut this material, you will still have an electret with aligned dipoles in your hands.
No, magnet rules apply here. The effect is due to molecular alignments, so it works the same as domains in a magnet - cut it in half, get two electrets, though weaker ones.
That detector array seems like a perfect candidate for some creative PCB design. Make a 5x5 array on a maybe 50mm square board with strategically located power pads around the edges and solder as many as you want into a plane.
A moving magnetic field induces an electric field (e.g. magnet dropped through a copper pipe). And dually, a moving electric field induces... a magnetic field! So dropping the electret through an iron pipe will induce magnetic flux in the pipe. When dropping a magnet through the copper pipe, a back-mmf is produced by the eddy currents, which counteract the force of gravity and slow the magnet down. So the magnetic flux induced by an electret dropped through an iron pipe should likewise induce a back-emf and slow down the electret's fall. (It would be best for the demo if the iron pipe was insulated so that the electret doesn't contact it, since the iron is conductive as well as ferromagnetic.)
Das zeigt den wahren Charakter und wer die Größe hat den ersten Schritt zu machen. Das zeigt den Charakter der Person.. ..nun wird es sich bei der anderen Person zeigen.... Gut gemacht! Lg
I’m guessing the van de graff generator produces a positive charge on its dome, pointing your finger at it gives a spiky shape for electrons to bunch up on and more easily get attracted through the air back across to the dome. I think it’s because the electric field density is much higher pointing into sharper shapes, making it easier to ionise the air. Also electrets are really cool, I’ve wanted to make one myself for ages. It would be really cool to see you make a capacitive motor using electrets and plates.
The adhesive on the aluminum doesn't conduct electricity. You can get copper tape with an adhesive that does conduct electricity. I used the copper tape to shield my guitar from outside interference. I don't know if this will affect the charging of the Electret but I did see some arcing between the layers of aluminum tape. You can solder to the copper.
I tried maximizing potential using some of the same ideas and added a few.. Composition Best Option: Fluoropolymers (e.g., PTFE-based liquid precursors) for their high dielectric constant and stability. Additives: Nanoparticles like barium titanate (BaTiO₃) or silica for enhanced dipole alignment and retention. Electric Field Application Optimal Field Strength: 10-50 kV/cm for uniform polarization without dielectric breakdown. Electrode Geometry: Tapered edge electrodes to prevent charge concentration at the edges and ensure field uniformity. Mold Design Tapered Edges: Narrow tapering at edges (15-30°) to reduce charge concentration. Material: Non-conductive ceramic molds with low thermal conductivity to minimize leakage. Cooling Dynamics Controlled Cooling: Gradual cooling rate (~1-3°C/min) to lock dipoles while avoiding stress. Thermal Gradient: Even temperature distribution across the liquid volume. Separation Plate Material: Thin polyimide film for insulation, coated with a fluoropolymer layer for high dielectric performance. Thickness: ~100 microns to maintain separation without significant loss of field strength. Environmental Controls Humidity:
Electret Condenser mics also have the advantage of not needing external power supplies. Normal non-electret condenser mics require external power supplies. Either batteries in the mic housing or an actual external supply which send DC up to the mic in the same cable the sound comes back down from. But because of lower current potential, they have lower voltage out and are typically lower end models.
Electrets do need an external power, they have a jfet inside that needs current. This current can be provided by the input, there is always some leakage. Electret is usually too weak to do anything but to drive a jfet gate. So a lot of electret mics do have a battery but those batteries tend to last very long time. It is possible for battery to simply go old sooner than it drains. Basic omnidirectional electret capsules are surprisingly accurate and consistent. Panasonic WM61-A costs pennies and is inside a lot of measurement mics, like ECM-8000. I have few dozen of those somewhere, and about a hundred of another similar models.. Really simple things to play around with, take op-amp and battery, bias the input to half the PSU and connect the capsule between input and output, slap capacitors to input to the opamp input&output, feedback/gain resistor and it is about done. In a lot of applications you don't even need to be careful what components and sizes to use..
@@squidcaps4308 Wrong! The additional circuitry requires power. such as the jfet yes. The mic capsule itself does not. Unlike a regular capacitance mic which requires an external DC potential applied across the plates.
Wow.. I absolutely learned something new today from you. That is quite amazing. A permanent static electric charge from a piece of plastic or what looked like a chunk of wax.
Can't believe I've never heard of this effect before. This might be the coolest thing I've seen all year, and I spend an unhealthy amount of time watching interesting science on UA-cam. How permanent is that electret?
It is also used for so called "poling" of plastic films... this whole process takes place in a giant oven with rollers and a corona brush... he's not quite accurate in the idea that it needs to be directly connected, although this will improve efficiency. Later, rolls of the stuff can be hazardous to work with, particularly if it has been metallized on only one side... I've seen lightning bolts jump between the layers as it is pulled off the roll. Both sides have less an effect there but take on a piezoelectric effect, and flexing a cut off piece of film can develop quite the surprise for the beholder under the right circumstances.
I saw a demonstration of a laden jar consisting of a glass cup sandwiched between 2 metal cups. It would burn a hole through a deck of cards when charged with a Vandegraph generator. Amazingly, you could remove the 2 metal cups and they held no charge but when placed back in/on the glass isulator the powerful charge returned.
If you want to bulk solder, grab some high density organic flouridated hydrocarbon with a high boiling point, make your arrays, coat them with paste-solder, just look for soldering gel or liquid solder or tin paste or atomic tin paste, then put whatever you are soldering into a catering tray, the ones they use at buffets or dinners for events, with a lid on it, a glass lid works better with a silicone seal so you don't gas yourself, then heat it up over some candles or something and you'll make a soldering environment that'll melt the solder and you won't have to do them all 1 by 1. There are a few videos on youtube of course but I have no idea what you'd have to search to find them.
the non crackhead version of this is called vapor soldering and you need to be careful with temperatures since the flourinated hydrocarbons will readily decompose into hydroflouric acid at a certain temperature.
You have finally put yourself into top tier tech UA-camrs. Your delivery is still a bit stilted but it's just my opinion. This video not only super educational but genuinely made me so curious
Seems that's a myth. Turns out the difference of sides comes from the fabrication process and serves no practical purpose. Not 100% sure, tho... Just what I was told.
Here's a thought. Does it repel dust? If a layer of material that repelled dust could be built into furniture or floors, etc. people would really go for that.
Holy cow, I just realized I was not subscribed to your channel!! Fixed that problem ASAP. I love your channel and all the cool things you teach and share in your journey!
always known of them, but never knowing theyre so easily made and so intriguing when made... by far your best video. youve grown :) could always go PCB and run 50x50 detectors, more! bicolour LEDs and a pnp/npn based detector? positive and negative? or... small slugs of PE electrets mounted like compasses on little gimbals... on water? these just raise more questions than they answer... can they discharge if shorted for long enough? or if used in a "wimshurst" type affair? perform the 'faraday ice pail" with one... shorted out pair of conductive plates? what if you make a bunch that are tapered, to clip together into a ring? do they attract the same material from both ends, or is there a triboelectric order? "field lines"? a loop of static charge, but what if its spun? near a magnet? can also see the benefit of a pressure vessel? increase the breakdown voltage... easier than pulling silly high vacuum...
So cool. I'd always heard of electrets in the context of electret microphones, and so always associated them with capacitance. But, it was one of those things I'd always heard, but never really looked into. Probably much like yourself before diving into this rabbit hole. Thanks for sharing your experiences and this amazing and unique footage of things most people couldn't even imagine. You're a true legend.
Would be very interesting to see the effects of electrets and magnets with their fields perpendicular and/or moving relative to each other, moving conductors through those fields
Static Field Detector: The problem can be modeled in many ways, but the way I chose to see it for this explanation is by modeling both the resistor and your finger as charged particles approaching the source, modeled as another charged particle. Your finger has a charge closer to the one of the source, but is much closer when you approach it, so the the electrically charged "particles" that were going to the resistor are pulled away to go to your skin and vice-versa.
As a furniture maker I'd love to see that grid of LEDs built into something like a coffee table top with a translucent material as the top to diffuse the light. With a set of coasters made out of the same material as the puck you could create a really cool effect wherever someone is resting their cup.
I have to admit I was thinking would be amazing to make a detector that has more ‘pixel density’. (And or- I don’t know if this is possible but- ‘intensity modulation’ so it glows brighter or dimmer at the center and edges of the field..)
I made one of those detectors to warn me if I might zap electronic components while soldering. Mine was stupidly sensitive though because it could detect me from 8 or 10 feet. It used a 9V battery and I think a JFET. It was useless as a warning but fun to play with. Thanks for showing how an electret is made. I kept coming across the word when making a crazy big condenser microphone with a 5" diaphragm for making infra-sound recordings.
Our finger becomes a POINTY electrode, aaand a path to ground, this means that the charges can now flow to ground.Tis essentially forms a short circuit and less charge.Also, your circuit seems to be the classic darlington pair....which I agree is more simpler than using an op amp, but an op amp has more "controls" per se. When you first said "electrets" I thought you meant the microphone......boy was I wrong.......
Try the resin mixed with white quartz sand, quartz and glass are the best dielectrics, the difference is that quartz is piezoelectric, and provides a plus ;), basically a static energy battery, now you can understand the cases of Viktor Grebennikov and Edward Leedskalnin.
Thanks for watching! I mentioned the wrong Japanese scientist - Mototarô Eguchi was the man. Use code 50PLASMA to get 50% OFF plus free shipping on your first Factor box at bit.ly/4eHXfxx! Also, here are the links to Onshape ( Onshape.pro/PlasmaChannel ) and the custom transformer video: ua-cam.com/video/DkhpuuPljS4/v-deo.html . Let me know what you think about these really cool mysteries called Electrets!
how are they mysteries? lol they are well understood but i guess thats typical youtuber engagement bait
2nd reply second like
Being able to do that but in reverse would be fantastic, it would have a real application for space suit design too. A space suit that can repel lunar dust via permanent static charge would be a truly useful invention.
lol putting the plate contacts on the outside hahhaha!!!
Not an "antimagnet" then.
Do not recommend channel. Congrats.
I never even knew what an electret was until less than 20 minutes ago. What a crazy concept, I love it
I wish he explained it a bit better, from what I understood it's just like a balloon that you rob on your air... (?)
@@Alfred-NeumanI think it's like the balloon but if you melt it and the solidify the way the molecules point.
There is an electret microphone in your phone. Headsets also use them quite commonly. They are cheap and surprisingly accurate.
@@Alfred-Neuman The difference is that the balloon eventually loses its charge, but this keeps it for a long time. As an analogy: a magnetized nail is to a permanent magnet as the balloon is to an electret
They're used all the time in microphones. They sandwich an electret between two metal plates, the electret vibrates and the capacitance is measured after the signal is amplified by a JFET which is usually included in the actual microphone module. It is a real treat to learn such esoteric knowledge and to see experiments that very few, if any people have ever seen. And just 200 years ago if you lived on a farm all your life, you wouldn't even know what the ocean looks like. It's easy to take things like that for granted. But it's nice to take a moment to think about it.
Set the electret on a fixed stand. Take the detector and move it around behind it on a fixed distance. Now set your camera to a long-exposure and you will get an image of the complete electric field in high resolution..
That's a cool idea!
Even better, put a detector on a gantry that can trace out many points in a circle around the electret, and let the detector feed a microcontroller. Then you can model a digital representation of the field
Similarly, spin the sensor on a lazy Susan to get a far higher resolution image with a faster frame rate, with the same sensor and very little complexity.
A little higher resolution with a little more complexity could be had by spinning the sensor on two parallel axes where one is slightly offset from the other, so the LEDs trace spirograph patterns that cover most of the surface area. With a little clever counterweighting this could be done completely passively (no motors, just hand powered) with two lazy susans.
@@TimBlack1 are you a Lazy Susan sales person by any chance? 😆
How about using a pair of N- and P-channel MOSFETS for the sensing, with red and green LEDs to show the polarity.
Better idea: make lots of tiny electrit compasses that can turn to show the directions like a magnetic compass.
More specifically Bi-color Red/Green LEDs.
Came here to say the same 😅❤
Edit: would use npn/pnp bjt of course 😅
Diffusers in front of the leds would be easier to see the field and maybe it would work better mounted on a proper pcb instead of free floating solder joints
Dagnabbit. I was going to suggest something similar. Bipolar sensors and dichromatic lights to indicate electric field polarity and intensity simultaneously.
You can use the electret to test the Poynting Vector if you'd like a follow-up video. A moving electret is a current of sorts. It should resist a change in position with a tiny force. A moving charge also generates a far field, a radio field. So, spinning one fast enough should generate a radio wave. (Due to Special Relativity, look for the relevant equations in a Physics book. Breaking Radiation.)
okay what?! thats really interesting. I'll look into this.
Super interesting point! I’d love to seem him test your idea.
I do wonder how this would interact with a regular magnet, or any type of magnetic field
@@PlasmaChannel According to relativity, a magnetic field is just an electrostatic field seen from a different frame of reference, so yes, it should generate a radio wave, but you'd have to spin the thing pretty damn fast to get a decent frequency.
You'd have to spin it at the desired frequency right? So like 60 million + rpm...
Everytime I start to believe that i know everything in fundamental sciences these very intelligent science youtubers come up with videos about things that are not taught or available mainstream. I love your videos plasma man. I've always used electret microphones in my electronic projects always thought that electret is some trade name or something this video proved me wrong and made me Learn something new. Wonderful! Thanks.
Maaaan, diggin into 60's patents and inventions bring up topics of science you think its crazy, yet there's always a simple ass reason
Do engineering as well as high school science, easy. ;)
Stuff like this is mainstream, just not school level.
@thekaxmax what undergraduate engineering school has "electrets" in the syllabus? I have a BE in electronics. I think maybe materiel science and engineering but electrets are surely some advanced pg or phd level stuff...
So permanent Realy means permanent? Dosent lose the proprities? This looked like a cool way to do a puzzle for a escape room. Is there anyway I could buy one of these?
@vaibhavhayaran they are very new, and only covered in tertiary level courses. 'Not high school' is the important point here.
Rather than making a 10 by 10 sensor field: Mount your current sensor field on a jig that you can move both horizontally and vertically, either manually or by stepper motors with belts. Then you can mount your electret in front of the sensor field and move the field about while recording the results with a static (non moving in this case) camera on a tripod.
That should give you an immense amount of data if you overlay the frames additively.
I'd love to see this in action if you have a chance.
I was thinking the same. He could mount his detector on his 3D printer and just use some g-code sent through the usb port to move it around.
Quick note, but when melting wax, candle makers use a bain-marie. A water bath. You fill the pan with water then put another container within, stood up on a couple of blocks. The wax goes in that. That way the temperature can never get above 100C. It's fine for wax (and also chocolate come to think of it), and it won't get high enough that the wax might ignite or char.
You also melt hide glue that way. It's used to construct stringed instruments.
If you look at electret papers its actually common to heat the wax above 100C to drive off water. A water bath is typically not used for this reason. Some of the papers I read used a temperature controlled oven for this.
Double boiler
@@carpdog42 I can see that, but when doing it at home on a cooker, there's a fair chance that, if the wax vapourises, it can catch light, particularly if it's a gas cooker. Not just catch light, but explode and send burning bits of wax all over the place.
It's dangerous, and a bain marie (AKA double boiler, thanks @thezfunk) is what candle makers use. Perhaps steam might affect the dielectric strength of the wax. In that case it might be good just to have a non-water fire extinguisher ready, because water would do what it does with burning fat in another common way to burn your house down.
That is, if a pan of oil or fat catches fire, and you add water, the water sinks underneath, since it's more dense than oil or fat. The water sinks, then immediately heats up and boils, almost instantly, causing steam to fly out everywhere, throwing burning fat all over the place with it.
It looks like setting off a pan of petrol, fire brigades will sometimes demonstrate that to the public, you can find video of it. Huge explosion! Starts lots of house fires.
So from that point of view maybe use a bain marie. If it buggers up the dielectric, then instead have a non-water fire extinguisher suitable for putting out burning fats or fuels. Usually, I think, that means the powder type.
@@greenaumit's just oil in a pot. If you can work a deep frier you can melt wax without a water bath.
This is the kind of happiness social media can't buy
I know we are on social media.
I used to work for 3M. We used Electret fibres for air filters.
I have two of those in my house.
And in the 1990's, I bought a couple for the house I owned then too.
Makes for a very good filter for the smallest particles doesn't it? I have used a few metallic static charged filters but they lose their charge with time
@@Technichian462 3M bought the technology from a Dutch firm decades ago. It's really interesting how they make charged fibres, but I'm uncertain how much is a trade secret: it's enough to know that once the fibres have been formed into a non-woven fabric that the overall charge is zero (as measured form the outside), and yet individual fibres retain their charge like little capacitors.
@@DarkAttack14 Unlike HEPA filters, which use physical restriction to block particles, Electret fibres actually pull particulates from the airstream. Did you know that the masks used by most folks during the PN-demic were actually useless in thwarting viruses by the way?
@@chriscarter2101 That's really interesting!
Would that be the same kind of tech in like a 3M respirator?
Thanks! I learned something new!
For the high-res version, I think you'll have an easier time designing a PCB and having it assembled for you by JLCPCB or PCBWay. You might even be able to have the sponsor the video, I've seen them sponsor quite a few maker videos featuring their PCBs
This! And that way you can make it even higher than 10x10.
Beat me to it! MM resolution on the sensors and the whole thing assembled for you. They'd probably do it for free for a sponsor bit, too, which I'm okay with.
Beat me to this. Super happy to help you design it.
The use of some neopixels or something would be awesome too, can use a variety of colors depending on how far it is
+ Some are small enough to allow a muchhhh greater density so you can see so much more of the field
These are also used in commercial radon detection systems as well. A small disc electret (with both plates permanently attached) is charged (by the manufacturer) to a known static voltage, sent out to vendors, which take them the locations (to be evaluated for radon) and placed in a reusable chamber with known air volume exposed to its surface. To activate the detector you simply expose opening of the chamber to the location air. After x number of hours (or days) the electrets charge voltage is read out on a handheld device, and the amount of radon it was exposed to is calculated based in the size of the container and the net decrease in the electrets charge voltage. The principal of these systems is Radon's decay products (in the air) will slowly strip the electret of its charge, and can be easily read out with a static detector (in the handheld device). After several exposures the electret will no longer have enough charge for the reader to detect and you will have to send your electrets back to the manufacture for "refurbishment" I think I'm going to try to remelt them (after they are fully discharged from use) and cool under a high voltage source and see if I can find out the range needed to "refurbish" them myself!😁
Are you sure it is an electret? If I understand the concept, like a magnet, once charged, they don't discharge. Otherwise, it would be a capacitor that can be charged and discharged.
An electret has the molecules arranged in the body of the material, where it remains, until you melt the material and allow the molecules to discharge, which is why they can have a permanent charge.
A device that detects radiation by losing a voltage charge is called a dosimeter, and it works by having the radiation discharge the material over time, and the faster the discharge, the higher the radiation. But it works with materials that are not permanently charged, but are charged before use.
Wild. Inside out smoke detector lol
@@MadScientist267 Correct, radon gas is everywhere, and it is worse underground, which is why some people report feeling better underground. Mammoth Caves had a village built underground for some people, and they lived there until they discovered the radon gas phenomena, and the damage it causes, is very bad. Which is why they have radon gas detectors.
The word electret sounded vaguely familiar but I couldn't place it until the last frame when you mentioned microphones. I remember the word from electronics kits and tape recorders when i was a kid back in the 70s and 80s "electret microphone." It was just a word back then. I had no idea what it meant. Interesting video, thanks.
Thanks for that connection, I think most of us (old enough) vaguely remember that too
Same here! The first thing that came to my mind when I saw the title was - a microphone. My young self heard from dad that it was "capacitive", as opposed to 'dynamic' that were "inductive" because they were based on a coil and a magnet, just like every single speaker we've had. I remember wondering, if that's possible, then why don't we have capacitive speakers then? Imagine my grin when I understood how piezo-speakers from cheap toys exactly worked :D
I am extremely happy to have learned of this. Thank you for sharing your knowledge.
You should try some grass seeds on top of water. Halliday Resnick had many pictures showing them to work similar to iron filings for electric field
I love how you revel in your failures. So authentic. So reassuring. Keep up the great work
Well done Bro. Dielectric Fields are fascinating. I am glad you are into electrets. Thomas Townsend Brown made the best ones his unreleased patents are on the TT Brown Family website. Using Heavy elements like Tungsten Carbonate ans Carnauba Wax making an tuned potential battery
This is super cool! I’m glad you made it work. You made it look easy
It would be cool if you made a 3-dimensional array and plotted the field strength in 3D. You could streamline the processes using PCBs.
Great ideal, same as in my comment. That would be awsome.
I can imagine something like GreatScott's 3D led matrix
Or you could try one sensor on a 2D or 3D positioning system
@@AdrianBoyko For example mount the sensor on the head of a 3d printer. If you could move that freely to any position you could take a picture each time and at the end merge them together
Really cool project Jay! And the detector too! And I love your workshop with the backlit plants 🪴
This guy deserves more
More what? More bots?
@@plotholedetective4166 More Like Praises Brother
@@plotholedetective4166 definetly more volts. he'd like that
"Thumb - Power and influence. Men wearing a ring on their thumb has long been viewed as a symbol of power or influence. It has also been associated with high-class society and royalty."
he's got 900,000 subs, what more?
That was a very cool thing you explained. Much food for thought.
This is how face mask filter media can be higher filtration efficiency than just the fabric itself. The material is made from polypropylene and is charged between charged bars.
Not just face masks. It is used much more in furnace filters! They are really effective when combined with a box fan. I had a 20 inch box fan and then used 5 furnace filters to create a big whole apartment air filter setup. The downside is 5 high merv furnace filters can cost up to 80 bucks and they only last around 3ish months depending on use time
@@DarkAttack14 Reminds me of the old electrostatic filters, I had one on my furnace, but they need constant maintenance.
You just gained a sub. As a science enthusiast, I have never heard of this concept. I'm truly excited to see the practical applications of electrets in action.
This was extremely interesting. Thank you!
I've been fascinated by electrets for a little while now. So cool that you made a video on making one!
Honestly this video was perfectly timed. I was about to put some money down this week and buy what I've learned now the wrong materials to build this exact electret. Thank you so so much for making this video right now. You saved me days and days of work :-)!!
Jay Bowles you're such a modern genius it's amazing to watch your videos! All the best!
Thank you, I strive to be as original as I can be with my projects!
5:24 You made a finger gun.
And with the contents of this channel, it's obvious that your finger guns would be electron ray guns.
He needs a permit for that finger gun...
I really enjoyed this video. Perfect example of persistence pays off!
My biggest note would be that as I went over the papers on this subject, some of the more "recent" ones on using wax (1960s I think) talked about how it was safer and more reliable to create the wax disks first, and then electrify them while solid. There is a solid phase change in the carnuba wax somewhere around 70C which is the sweet spot. Also, of note your wax had some large stress fractures, which can be minimized by adding some bees wax and/or cooling more slowly.
You really beat me to my own project here, but you also solved a lot of the issues slowing me down. I wasn't confident at using 3d printed materials as a mold due to temperatures involved, and so I designed molds to pour silicone molds. My first attempt failed the same way except since my plates were well insulated the sparking happened right down the side of the solid wax and left tracks down the inside of the mold and on the wax.
I don't know if this will help, but I did a study on why high voltage wires have ribbed insulators. Turns out the ribs increase the length of the path needed for the original contact. Hard to mold ribs in the substance without a four part mold, but I would want to pour that object from the side anyway to make better contact with the plates.
Resin materials can support higher temperatures. use a resin 3D printer.
I did indeed learn a lot. I already knew about Electret condenser microphones... I did not know how they differed from regular condenser mics aside from not needing phantom power, but very early in the video I finally understood where they got their names, and why they don't need power :D
Wow! I don't know those exist. Why don't people talk about it more?
Especially considering that those can be just chunks of plastic. Should be pretty easy to mass-manufacture
Most people think science is for nerds... while using hundreds of modern inventions a day that eould not exist without science... Then they voted for Trump.
Most people are pretty freaking stupid and uncurious.
I love the way you show your process, starting with incomplete design and then refining. Helps the viewer understand principals of electricity by first doing things wrong then showing how to do the correctly and why. Discovery method of teaching is very good.
imagine how strong it would be charged if you apply a voltage across thats at 95% of the dielectric breakdown for that thickness.
40kv for PE this thick is nothing. 1 inch would be able to withstand at least half a megavolt. (>19MV/m for solid PE)
you could stick two electret discs together with this field strength
theres a method of forming lichtenberg figures inside clear acrylic plastic by bombarding it with a electron accelerator to charge it up massively and then ram a grounded spike into it to discharge it in one snap.
The pattern will change depending on polarity too, negative has some truly beautiful fern like patterns.
Would it be dangerous if it was charged to that level?
What if he just made it thinner, would that be equivalent?
What would be the lifting force for something like this? Like how powerfull could we make these if we REALLY tried? Enough to lift a kilogram? Several kilograms?
You'd have to make a big slab of material with the field applied only in the middle, that's the only way to avoid breakdown of the surrounding air. Then cut out the electret bit. But yet, if you build it that way to solve the breakdown problem, you could turn the voltage way, way, way up. But there is a limit: Once you have most of the molecules lined up, no amount of extra voltage will give a stronger electret.
Ya know... since water molecules have a posituve/negative orientation... it would be tricky... but I bet you could make an electret out of ice...? You would have to freeze the water while it was being exposed to the external charge...
I'm not sure that it would be all that tricky as long as you use pure distilled water. Pure water doesn't conduct electricity.
@@johnharris5786 you do get some current tho as water will dissolute into hydroxide and hydronium ions
@@johnharris5786 also you would probley need to cool the water very quickly so it cant crystalize as during the crystallization the dipoles will align preventing the effect
@@a.kjfhkziujsfdgbskjxfyhgfl2332 Two good points. I guess you would have to work out if the amount of power dissipated by the water is enough to stop cooling in the first place. If the current is small enough it shouldn't matter too much? As to the second point, would it be possible to cool the water down to zero or even sub zero and keep it a liquid by agitating it maybe? You then only need to apply the electric field just before it freezes.
You should try your hand at making a Birkland Eyed generator, making nitric acid from air using a plasma arc. Some designs used magnets or electromagnets to force the arc into a disc, donut shape or others to increase efficiency.
please try this "weird" phenomenon using your electret :
When a magnet and an electret are near one another, a rather unusual phenomenon occurs: while stationary, neither has any effect on one another. However, when an electret is moved with respect to a magnetic pole, a force is felt which acts perpendicular to the magnetic field, pushing the electret along a path 90 degrees to the expected direction of "push" as would be felt with another magnet.
Agree ! please do it
I WOULD ALSO LIKE TO SEE THIS!!!!
couldn't this be used for midair turning
This is SO FRICKING COOOLL!!! Jay i love you, one of my favorite youtubers.
When you point your finger at your Van de Graaff generator, it doesn't actually lose charge, or at least not a lot. The static electric field from the generator causes the electrons in your finger to be either attracted on pushed away, depending on charge of the sphere. The result is a charged finger, which creates it's own electric field, which is opposite to the primary field and completely offsets it within your finger. But this field extends beyond your finger, weakening the primary field. If you get your finger close enough to the generator, it's field becomes strong enough to reduce the field at the detector below the detection threshold.
This is the kind of shit we need. Freaking Awesome.
Very bien , félicitations pour votre démonstration.
I think your finger was acting as a ground for the Van De Graffe electric field.
Puzzle for me too. Either that was wireless current to ground (finger lightning rod facilitating cloud discharge) or the space between the battery/antenna plate and the Jay/tesla plate was being made a polarized dielectric (capacitor?), and I'm not sure it's not both.
@@cherylm2C6671 Same, I think. Even a capacitor is a conductor with high dielectric resistance. Sparks/lightning are dielectric breakdown, but there is also less violent transfer of charge, which accumulates gradually. In this case, charge was diverted away from the sensor to his finger. Likely, if the finger was insulated, once it accumulated enough charge, the diversion would cease and the sensor would light up again.
He was grounded, for not wanting to give an explanation !
Love all your videos. You are definitely among the youtubers that convinced me to finally get into electronics and I am now working on my first project (as an adult, I took electronics in high school)
I had no idea that a material could have a permanent static charge. Very cool video. Thank you for sharing with us.
In theory any insulating material can demonstrate the phenomenon, however the melting is the key. In the liquid state, the molecules are influenced by the external electric field. As it solidifies, the molecules retain their physical orientation, and so a permanent field. It's very similar to how a permanent magnet is formed... the alloy doesn't need to "melt" but it is heated above its curie point and exposed to a strong external magnetic field as it cools. When it is crystalline again, the grains are all oriented and locked in with the original field, and a permanent magnet is created.
It wouldn't make sense for this to not be possible... it would break the idea that magnetism and electric fields are two sides of the same coin.
My question: Does an electret retain its polarization when exposed to ionized air?
@@janhemmer8181 Good question, and while I don't know for sure, it likely doesn't affect it much if at all. There's nothing intrinsic to ionized air that should have an effect far as I'm aware. Elevated temperatures and ionizing *radiation* would degrade it however, by causing mechanical/physical effects that disturb the ability of the material to maintain its polarization at the molecular level.
@MadScientist267 My reason for asking is because i know this is what happens with a plastic surface that has been rubbed with a cloth.
Hovering above it with a grounded spiked metal rod will instantly transfer ionized air molecules of opposite charge to that surface and cancel the electric field.
I cannot see how this case will be any different.
The material of course will stay polarized but no outside effect of that polarization will be noticable.
@@janhemmer8181 The key difference is where the charges are in the material. When you rub dissimilar materials together, the charges that are created are held only on the surface of the material(s). In the case of the electret, these charges are trapped within the entire bulk of the material. They aren't able to freely "escape" as they are in a material that has simply been rubbed.
They weren't lying about how the static charge in N95 masks actually attracts even smaller particles (like that one particle).
That is a Cool material!
You know what would be even more cool? Building two of them and then show us how they attract/repel just like we are used to do with common magnets ❤
Another idea for mapping the field. Have just one sensor, or a row of them and move the sensors across smoothly while using a long camera exposure. Not sure how well it would work but might be easier than creating a huge grid. A challenge there would be ensuring it moves at a constant speed.
Or. POV array of sensors!
this channel is very reminiscent of the old TKOR with Grant, fills a little void in my heart
Hmm... if you cut a magnet in half, you'll get 2 magnets - both with north and south poles. However, what happens if you cut an electret in half? Would you have one positively charged and one negatively charged, or will you have 2 with both types of charges?
Not really, electrets can be one single charge. The way this one is made its basically a fixed gradient. You could cut it and put it back together, it won't change when cut apart like magnets do.
They work differently on a fundamental level, so you wouldn't expect the same behaviour. Magnets create two magnets when cut in half because magnetic monopoles don't exist (a magnet is a magnetic dipole). Electric monopoles do exist though, so you it is theoretically possible to cut an electret in half and get two electric monopoles (rather than another electret/dipole).
Yes it would behave similar to a magnet, maintaining a positive and negative pole no matter where you slice it. That is due to the way he is making these. He applies a polarized field while it is cooling leading to polarized molecules lining up along the field. If instead he bombarded a wax or plastic brick with an electron gun, he could in theory create a uniform distribution of excess electrons such that when sliced the two halves would not be polarized but simply uniformly negatively charged.
Yes. The system essentially aligns electric dipoles rather than storing charge. When in liquid form, dielectric dipoles align, and as the material solidifies, the dipoles remain in place. This creates an electric field. When you cut this material, you will still have an electret with aligned dipoles in your hands.
No, magnet rules apply here. The effect is due to molecular alignments, so it works the same as domains in a magnet - cut it in half, get two electrets, though weaker ones.
That detector array seems like a perfect candidate for some creative PCB design. Make a 5x5 array on a maybe 50mm square board with strategically located power pads around the edges and solder as many as you want into a plane.
What happens if you drop the puck down a copper tube? Does it create eddy currents, like a magnet does?
A moving magnetic field induces an electric field (e.g. magnet dropped through a copper pipe). And dually, a moving electric field induces... a magnetic field! So dropping the electret through an iron pipe will induce magnetic flux in the pipe.
When dropping a magnet through the copper pipe, a back-mmf is produced by the eddy currents, which counteract the force of gravity and slow the magnet down. So the magnetic flux induced by an electret dropped through an iron pipe should likewise induce a back-emf and slow down the electret's fall. (It would be best for the demo if the iron pipe was insulated so that the electret doesn't contact it, since the iron is conductive as well as ferromagnetic.)
magnetic flux or magnetic current? PLEASE DROP THE PUCK DOWN AN IRON PIPE!!!
@johnharris5786 copper pipe.
@@zippythinginvention No, I think the puck should be dropped down an iron pipe or even a coil made of iron. See Jordan's comment.
@johnharris5786 Jordan is wrong. Copper is more conductive.
Das zeigt den wahren Charakter und wer die Größe hat den ersten Schritt zu machen.
Das zeigt den Charakter der Person..
..nun wird es sich bei der anderen Person zeigen....
Gut gemacht!
Lg
I’m guessing the van de graff generator produces a positive charge on its dome, pointing your finger at it gives a spiky shape for electrons to bunch up on and more easily get attracted through the air back across to the dome. I think it’s because the electric field density is much higher pointing into sharper shapes, making it easier to ionise the air.
Also electrets are really cool, I’ve wanted to make one myself for ages. It would be really cool to see you make a capacitive motor using electrets and plates.
I love how eye opening these videos are and I love that he explains things in a way rly anyone can understand and be able to learn new things
The adhesive on the aluminum doesn't conduct electricity. You can get copper tape with an adhesive that does conduct electricity. I used the copper tape to shield my guitar from outside interference. I don't know if this will affect the charging of the Electret but I did see some arcing between the layers of aluminum tape. You can solder to the copper.
I tried maximizing potential using some of the same ideas and added a few..
Composition
Best Option: Fluoropolymers (e.g., PTFE-based liquid precursors) for their high dielectric constant and stability.
Additives: Nanoparticles like barium titanate (BaTiO₃) or silica for enhanced dipole alignment and retention.
Electric Field Application
Optimal Field Strength: 10-50 kV/cm for uniform polarization without dielectric breakdown.
Electrode Geometry: Tapered edge electrodes to prevent charge concentration at the edges and ensure field uniformity.
Mold Design
Tapered Edges: Narrow tapering at edges (15-30°) to reduce charge concentration.
Material: Non-conductive ceramic molds with low thermal conductivity to minimize leakage.
Cooling Dynamics
Controlled Cooling: Gradual cooling rate (~1-3°C/min) to lock dipoles while avoiding stress.
Thermal Gradient: Even temperature distribution across the liquid volume.
Separation Plate
Material: Thin polyimide film for insulation, coated with a fluoropolymer layer for high dielectric performance.
Thickness: ~100 microns to maintain separation without significant loss of field strength.
Environmental Controls
Humidity:
And what was your result?
Electret Condenser mics also have the advantage of not needing external power supplies. Normal non-electret condenser mics require external power supplies. Either batteries in the mic housing or an actual external supply which send DC up to the mic in the same cable the sound comes back down from. But because of lower current potential, they have lower voltage out and are typically lower end models.
Electrets do need an external power, they have a jfet inside that needs current. This current can be provided by the input, there is always some leakage. Electret is usually too weak to do anything but to drive a jfet gate. So a lot of electret mics do have a battery but those batteries tend to last very long time. It is possible for battery to simply go old sooner than it drains.
Basic omnidirectional electret capsules are surprisingly accurate and consistent. Panasonic WM61-A costs pennies and is inside a lot of measurement mics, like ECM-8000. I have few dozen of those somewhere, and about a hundred of another similar models.. Really simple things to play around with, take op-amp and battery, bias the input to half the PSU and connect the capsule between input and output, slap capacitors to input to the opamp input&output, feedback/gain resistor and it is about done. In a lot of applications you don't even need to be careful what components and sizes to use..
@@squidcaps4308 Wrong! The additional circuitry requires power. such as the jfet yes. The mic capsule itself does not. Unlike a regular capacitance mic which requires an external DC potential applied across the plates.
Wow.. I absolutely learned something new today from you. That is quite amazing. A permanent static electric charge from a piece of plastic or what looked like a chunk of wax.
Can't believe I've never heard of this effect before. This might be the coolest thing I've seen all year, and I spend an unhealthy amount of time watching interesting science on UA-cam.
How permanent is that electret?
rule of thumb is that its as permanent as the electret is hard. ceramic electrets last really long time, just a rule of thumb due to factors.
It is also used for so called "poling" of plastic films... this whole process takes place in a giant oven with rollers and a corona brush... he's not quite accurate in the idea that it needs to be directly connected, although this will improve efficiency.
Later, rolls of the stuff can be hazardous to work with, particularly if it has been metallized on only one side... I've seen lightning bolts jump between the layers as it is pulled off the roll. Both sides have less an effect there but take on a piezoelectric effect, and flexing a cut off piece of film can develop quite the surprise for the beholder under the right circumstances.
I saw a demonstration of a laden jar consisting of a glass cup sandwiched between 2 metal cups. It would burn a hole through a deck of cards when charged with a Vandegraph generator. Amazingly, you could remove the 2 metal cups and they held no charge but when placed back in/on the glass isulator the powerful charge returned.
If you want to bulk solder, grab some high density organic flouridated hydrocarbon with a high boiling point, make your arrays, coat them with paste-solder, just look for soldering gel or liquid solder or tin paste or atomic tin paste, then put whatever you are soldering into a catering tray, the ones they use at buffets or dinners for events, with a lid on it, a glass lid works better with a silicone seal so you don't gas yourself, then heat it up over some candles or something and you'll make a soldering environment that'll melt the solder and you won't have to do them all 1 by 1. There are a few videos on youtube of course but I have no idea what you'd have to search to find them.
the non crackhead version of this is called vapor soldering and you need to be careful with temperatures since the flourinated hydrocarbons will readily decompose into hydroflouric acid at a certain temperature.
nah this is AWFUL advice
@@drkastenbrot HF is one of the chemicals that really scares me (and I have some pretty bad chemical burns).
You have finally put yourself into top tier tech UA-camrs. Your delivery is still a bit stilted but it's just my opinion. This video not only super educational but genuinely made me so curious
3:33 I thought you said you can't cook?
I never knew this was a thing and I love science. Thank you very much for sharing this. Crazy cool.
7:57 You should always wrap things in foil shiny side inward.
I learned that from the movie Multiplicity, the nanny clone gave a lot of good advice.
Seems that's a myth.
Turns out the difference of sides comes from the fabrication process and serves no practical purpose.
Not 100% sure, tho... Just what I was told.
bs !
Thanks a million for you experiments. Your works are really inspiring. Stay happy dude
0:15 your mama
That's really interesting! I wonder how it would behave with a magnet embedded in it...
A great demo of Electrets .
Wow I want one so bad! I could come up with so many STEM activities at the library I work at with one. Really cool video!
VERY INTERESTING :)
THANK YOU FOR SHARING :)
THANK YOU FROM ISRAEL :)
The Uncle Lazer of science
That was super cool! Loved it!
I'm honored you enjoyed
Here's a thought. Does it repel dust? If a layer of material that repelled dust could be built into furniture or floors, etc. people would really go for that.
Holy cow, I just realized I was not subscribed to your channel!! Fixed that problem ASAP. I love your channel and all the cool things you teach and share in your journey!
This is fascinating.. it feels like there should bee aome amazing applications to this
always known of them, but never knowing theyre so easily made and so intriguing when made...
by far your best video. youve grown :)
could always go PCB and run 50x50 detectors, more! bicolour LEDs and a pnp/npn based detector? positive and negative?
or... small slugs of PE electrets mounted like compasses on little gimbals...
on water?
these just raise more questions than they answer... can they discharge if shorted for long enough? or if used in a "wimshurst" type affair?
perform the 'faraday ice pail" with one...
shorted out pair of conductive plates?
what if you make a bunch that are tapered, to clip together into a ring?
do they attract the same material from both ends, or is there a triboelectric order?
"field lines"?
a loop of static charge, but what if its spun? near a magnet?
can also see the benefit of a pressure vessel? increase the breakdown voltage... easier than pulling silly high vacuum...
I like all your jewelry that you're always wearing 👏👏❣️❣️❣️
I hope your Facebook page is working well and that format works well for you. 👍👍💟
So cool. I'd always heard of electrets in the context of electret microphones, and so always associated them with capacitance. But, it was one of those things I'd always heard, but never really looked into. Probably much like yourself before diving into this rabbit hole. Thanks for sharing your experiences and this amazing and unique footage of things most people couldn't even imagine. You're a true legend.
Awesome content, thanks for sharing the creative process and trials.
I'm glad I watched this video. It's the first time I have understood what an electret actually is.
Behold: the electret urinal cake! 😄
Fascinating.
Would be very interesting to see the effects of electrets and magnets with their fields perpendicular and/or moving relative to each other, moving conductors through those fields
I see where you are going here.....and I like it.
Fantastic experiment. Thanks for sharing 👌
Static Field Detector:
The problem can be modeled in many ways, but the way I chose to see it for this explanation is by modeling both the resistor and your finger as charged particles approaching the source, modeled as another charged particle. Your finger has a charge closer to the one of the source, but is much closer when you approach it, so the the electrically charged "particles" that were going to the resistor are pulled away to go to your skin and vice-versa.
Really enjoyed this, having a stressful day, was just what i needed ❤
This is by far the coolest video I have seen all year. And we're at the end of the year here. Congrats, instant subscribe from me.
Little do you know your getting closer to the holy grail 😊
As a furniture maker I'd love to see that grid of LEDs built into something like a coffee table top with a translucent material as the top to diffuse the light. With a set of coasters made out of the same material as the puck you could create a really cool effect wherever someone is resting their cup.
Add photophores on nanoelectret, trivial finish fx.
This is neat! Never heard of these before, good stuff mate
That was cool, especially the applications at the end. I have seen “electret microphone” listed on specs or ads, but never knew what it was!
I have to admit I was thinking would be amazing to make a detector that has more ‘pixel density’. (And or- I don’t know if this is possible but- ‘intensity modulation’ so it glows brighter or dimmer at the center and edges of the field..)
Was it that the high energy density of your body and arm were both disrupting the normal field density by acting as kind of a sink
I had no idea electrets existed until this video- what a cool thing! So many interesting possibilities.
I made one of those detectors to warn me if I might zap electronic components while soldering. Mine was stupidly sensitive though because it could detect me from 8 or 10 feet. It used a 9V battery and I think a JFET. It was useless as a warning but fun to play with. Thanks for showing how an electret is made. I kept coming across the word when making a crazy big condenser microphone with a 5" diaphragm for making infra-sound recordings.
Our finger becomes a POINTY electrode, aaand a path to ground, this means that the charges can now flow to ground.Tis essentially forms a short circuit and less charge.Also, your circuit seems to be the classic darlington pair....which I agree is more simpler than using an op amp, but an op amp has more "controls" per se. When you first said "electrets" I thought you meant the microphone......boy was I wrong.......
Try the resin mixed with white quartz sand, quartz and glass are the best dielectrics, the difference is that quartz is piezoelectric, and provides a plus ;), basically a static energy battery, now you can understand the cases of
Viktor Grebennikov and Edward Leedskalnin.