 |
 | Home | Contact Us | FAQ | Search & Site Map | Link to Us |
 | Sign In | Join | Other 45 Sites in Network |
Natural Science Forum / Physics / Acoustics / September 2006Can electricity flow through air w/out sparking?
Hi: Please forgive my persistence on this topic of wireless electricity and diaphragm-less speakers Can electricity flow through air w/out sparking? I guess that it could provided that the voltage is high-enough to break through the resistance of air AND the wattage is low-enough that it does not ionize or incandesce the air. Am I right? If so, could this high-voltage, low-wattage electricity be used to reproduce intelligent sound [e.g. music, speech, etc.] in the air itself? Once again I apologize if my posts seem redundant. Thanks, Radium > Hi: > [quoted text clipped - 13 lines] > > Radium The problem is not that your posts seem redundant, the problem is that your questions are inane. > Can electricity flow through air w/out sparking? I guess that it could > provided that the voltage is high-enough to break through the > resistance of air AND the wattage is low-enough that it does not ionize > or incandesce the air. "Breaking through the resistance of the air" IS ionizing the air. In short, if there's a gas in between two points, a "flow" of current/electrons between those points is going to break that gas down. The only way to avoid that is to not have any gas in the way - why do you think those glowing glass things we used to use were called "VACUUM tubes"? PLEASE learn something about the fundamentals before you ask any more questions like this. Bob M. > > Can electricity flow through air w/out sparking? I guess that it could > > provided that the voltage is high-enough to break through the [quoted text clipped - 13 lines] > > Bob M. Sorry. Ionization causes the ionized object have a number of electrons different from the object's native state. I thought electrons could flow through a substance that is otherwise-resistant w/out causing chemical changes [e.g. ionization] to the substance. My bad. > I thought electrons could > flow through a substance that is otherwise-resistant w/out causing > chemical changes [e.g. ionization] to the substance. What you think is a waste of Usenet bandwidth. Graham > Sorry. Ionization causes the ionized object have a number of electrons > different from the object's native state. I thought electrons could > flow through a substance that is otherwise-resistant w/out causing > chemical changes [e.g. ionization] to the substance. only conductors, when they flow through an insulattor they ionise it,  SignatureBye. Jasen Gee. This radium guy is superb and manufacturing entropy. >> Can electricity flow through air w/out sparking? I guess that it could >> provided that the voltage is high-enough to break through the [quoted text clipped - 13 lines] > > Bob M. Bob, he's a troll, he just asks stupid questions to get a rise out of us. The best thing to do is killfile him, or at least ignore his posts. If you do, hopefully, he'll go away. :-) >>> Can electricity flow through air w/out sparking? I guess that it >>> could provided that the voltage is high-enough to break through the [quoted text clipped - 18 lines] > The best thing to do is killfile him, or at least ignore his posts. If > you do, hopefully, he'll go away. :-) There's a swine mimicking a parrot in the room. > Hi: > > Please forgive my persistence on this topic of wireless electricity and > diaphragm-less speakers > > Can electricity flow through air w/out sparking? You haven't got the concept of electomagnetism yet have you ? DC won't do that but you can sure get AC power through the air. Graham > > Hi: > > [quoted text clipped - 4 lines] > > You haven't got the concept of electomagnetism yet have you ? > DC won't do that but you can sure get AC power through the air. Why can't DC flow through air? Static from touching a TV screen is an example of DC electricity moving through air. > Graham > > > Hi: > > > [quoted text clipped - 8 lines] > > Why can't DC flow through air? Why don't you go learn ? Then you wouldn't have to keep asking stupid questions. Are you simply lazy or just stupid ? > Static from touching a TV screen is an > example of DC electricity moving through air. No it isn't. Graham > Why don't you go learn ? He's trying. Why don't you teach him? > > Why don't you go learn ? > > He's trying. I have seen zero evidence of this. > Why don't you teach him? For a fee presumably ? Graham > > > > Hi: > > > > [quoted text clipped - 18 lines] > > Graham The sparks of a stun gun is another example of DC current traveling through air. > The sparks of a stun gun is another example of DC current traveling > through air. But not without an arc (ionization), which was the whole point in the first place. You apparently can't even follow your own line of reasoning (not surprising, since no once else can follow it either). Bob M. > > The sparks of a stun gun is another example of DC current traveling > > through air. > But not without an arc (ionization), which was the whole > point in the first place. Sorry. I was pointing out to another poster that DC current can flow through air. That poster claimed that only AC can travel through air. Is it possible for "arc" to have ionization thats small enough that it does not glow? If the extent if ionization is enough, then the arc becomes visible. Below that, it is invisible but can it make sound? Can diaphragm-less loudspeaker use low-level ionization to produce sound w/out lighting the air? > You apparently can't even follow your own line of reasoning > (not surprising, since no once else can follow it either). > > Bob M. > > > The sparks of a stun gun is another example of DC current traveling > > > through air. [quoted text clipped - 4 lines] > Sorry. I was pointing out to another poster that DC current can flow > through air. Not without the very ionisation you're seeking to avoid. > That poster claimed that only AC can travel through air. Correct. > Is it possible for "arc" to have ionization thats small enough that it > does not glow? Small enough perhaps not to notice visually in normal lighting. But it'll be there. Try turning the lights out ! Graham Look. For once, Radium actually has a point. It is possible for DC current to flow through air without producing a spark. I have done it myself. Take a variable (~30kV) DC high-voltage source. The one I used was valve- powered, by the way! Take two needles and clamp them so that each point points to the other needle's point, i.e. they're pointing at each other. Set the points 1cm apart. Obviously, the needles will not be electrically connected. Each needle is connected to one output of the high voltage generator. Start the generator at a low voltage. Crank it up, and before it does spark (experiment to find the voltage at which it does, if you like (if you damage your generator if/when it sparks, that's your problem, not mine)), there will be an "ion wind" between the needles. Sometimes you can even hear it, or see bits of dust in the air being blown around. Current is most definitely flowing, yet there is no spark. There is ionisation, but no spark as such. In the dark, you will likely see a blue glow at the needles' points. But it is still not a spark, in that it does connect the needle points. Turn the voltage down a little, and stick a candle flame between the electrodes. Have fun. Don't kill yourselves. Martin Disclaimer: This in no way endorses Radium's other stoopid questions. SignatureM.A.Poyser Manchester, U.K. http://www.livejournal.com/userinfo.bml?user=fleetie > Take a variable (~30kV) DC high-voltage source. The one I used was valve- > powered, by the way! Take two needles and clamp them so that each [quoted text clipped - 13 lines] > Turn the voltage down a little, and stick a candle flame between the > electrodes. A matter of semantics. What do you consider to be the distinguishing feature of a "spark," if not the glow? What you have in the above is a "spark" or "arc" - it's just one that is too feeble to result in a readily-visible ionization trail. Bob M. > "Fleetie" <fleetie@fleetie.demon.co.uk> wrote in message > [quoted text clipped - 13 lines] > > Bob M. I might vote for avalanche breakdown. Also, the current voltage curve for discharges is quite non linear and exhibits negative resistance in the spark region. Later... Ron Capik -- > Why can't DC flow through air? Static from touching a TV screen is an > example of DC electricity moving through air. Not even close. It's an example of an electric field being present, and that's ALL it is. Bob M. > Hi: > [quoted text clipped - 13 lines] > > Radium If you want the troll to say, just keep feeding him. > Can electricity flow through air w/out sparking? Define flow. > > Can electricity flow through air w/out sparking? > > Define flow. Movement of electrons in a current? > Movement of electrons in a current? Define movement > Hi: > [quoted text clipped - 13 lines] > > Radium Yes, electricity can flow through the air. But not in any way that really matters. It's more like a leak than a flow. There's always some ions floating around, and humidity makes it leak faster. Comb your hair and pick up small bits of paper with your comb, and see how long it takes the paper to fall. If electricity didn't leak through the air, the paper would stay stuck. This is different from a spark. When the air sparks, the resistance goes down to basically zero and huge currents can flow. Without the spark, it will only leak. Slowly. >Yes, electricity can flow through the air. But not in any way that >really matters. Oh, dear. Please see: 34c7e2hdkrr532niivoq9q6pbf1o9o0iap@4ax.com >>Yes, electricity can flow through the air. But not in any way that >>really matters. > > Oh, dear. Please see: > > 34c7e2hdkrr532niivoq9q6pbf1o9o0iap@4ax.com The URL seems to be broken. What are you trying to tell me? > The URL seems to be broken. What are you trying to tell me? I think "Radium is a clueless troll" would sum it all up quite nicely. Bob M. >>The URL seems to be broken. What are you trying to tell me? > > I think "Radium is a clueless troll" would sum it all up quite > nicely. > > Bob M. Clueless, maybe. But I think his questions are genuine, and I will continue to assume they are until he proves me wrong to my satisfaction. >>>The URL seems to be broken. What are you trying to tell me? >> [quoted text clipped - 5 lines] > Clueless, maybe. But I think his questions are genuine, and I will > continue to assume they are until he proves me wrong to my satisfaction. A bit of research will prove beyond a doubt that he is indeed a troll. >>>>The URL seems to be broken. What are you trying to tell me? >>> [quoted text clipped - 7 lines] >> > A bit of research will prove beyond a doubt that he is indeed a troll. A bit of research will also prove beyond doubt that you, Mike Rieves (aka Porky) are a technical ignoramus and a contemptible piece of sociopathic human waste who devoid of all commonly accepted moral and ethical standards. More information on this piece of pig sh.t can be found at: http://www.azwebpages.com/porky.htm > > I think "Radium is a clueless troll" would sum it all up quite > > nicely. [quoted text clipped - 3 lines] > Clueless, maybe. But I think his questions are genuine, and I will > continue to assume they are until he proves me wrong to my satisfaction. They might be genuine, but his followups imply that he is unwilling to learn anything and is unable to have any kind of meaningful discourse about technology. All attempts to point out his misconceptions are for naught. Are you really going to spend your time trying to explain things to him? Mark > >>Yes, electricity can flow through the air. But not in any way that > >>really matters. [quoted text clipped - 4 lines] > > The URL seems to be broken. What are you trying to tell me? That isn't a URL, its a link to a USENET message. SignatureService to my country? Been there, Done that, and I've got my DD214 to prove it. Member of DAV #85. Michael A. Terrell Central Florida >>>>Yes, electricity can flow through the air. But not in any way that >>>>really matters. [quoted text clipped - 6 lines] > > That isn't a URL, its a link to a USENET message. Whatever it is, it's not doing me much good. When I click on it, my browser tries to e-mail someone at 4ax.com, and when I paste it into the URL field I'm told that 4ax.com is not found. > >>>>Yes, electricity can flow through the air. But not in any way that > >>>>really matters. [quoted text clipped - 10 lines] > browser tries to e-mail someone at 4ax.com, and when I paste it into the > URL field I'm told that 4ax.com is not found. It has to be a clickable link, and exist on your news server for it to work. Apparently, its a link to this thread, and a message posted by Alan B on Wed 8:05 PM He also left the <> off the link. <34c7e2hdkrr532niivoq9q6pbf1o9o0iap@4ax.com> SignatureService to my country? Been there, Done that, and I've got my DD214 to prove it. Member of DAV #85. Michael A. Terrell Central Florida In alt.sci.physics.acoustics Radium <glucegen1@excite.com> wrote: > Can electricity flow through air w/out sparking? Yes. Tesla and Marconi did some interesting experiments with that phenomenon. SignatureA nation of sheep will beget a government of wolves. --Edward R. Murrow > In alt.sci.physics.acoustics Radium <glucegen1@excite.com> wrote: > > > Can electricity flow through air w/out sparking? > Yes. Tesla and Marconi did some interesting experiments with that > phenomenon. You mean they were able to pass electric current through air w/out arcing, sparking, or coronal discharge? > -- > A nation of sheep will beget a government of wolves. > --Edward R. Murrow >> In alt.sci.physics.acoustics Radium <glucegen1@excite.com> wrote: >> [quoted text clipped - 5 lines] > You mean they were able to pass electric current through air w/out > arcing, sparking, or coronal discharge? Yes. Tesla even had ideas about supplying power to machines that way. In a more modern context, that's how RFID tags are powered: there's no battery in the chip to drive the transmitter, the power for that is extracted from the carrier of the probe signal. Of course, all of this "electricity through the air" is AC, and is in conjunction with associated magnetic fields. Cheers, SignatureAndrew >>> In alt.sci.physics.acoustics Radium <glucegen1@excite.com> wrote: >>> [quoted text clipped - 14 lines] >Of course, all of this "electricity through the air" is AC, and is in >conjunction with associated magnetic fields. Well, there is no movement of charged particles through the air then. The form of energy flowing through the air is not electricity but electromagnetic radiation. That can even flow through a vacuum where there are no charged particles, molecules, atoms, or any of the usual subatomic particles. As for electricity to flow through air without sparking - that can be done, although not often practically, and there is a name for that phenomenon - "ionic current". In an ionic current, charge is carried by movement of ions. Where there are ions, there may also be some free electrons available to move charge. Ionic currents are usually less than 1 microamp. They are hard to target over major distances to anything other than a greatly isolated conductor (such as a target in the middle of a room from closer to the target than to the nearest wall, floor or ceiling). Ionic currents mostly come from corona, although they could flow through air ionized by ionizing radiation. If you experiment with sources of ionizing radiation that are short of very significant health hazard, don't expect 15 volts to push through more than a few nanoamps (and that may be optimistic). And don't expect blacklights or UV LEDs to make air conductive - doing that with UV requires wavelengths below 200 nm, maybe well below (184.9 nm ozone-forming mercury wavelength may not work). - Don Klipstein (don@misty.com) > ?? wrote: > >>> Yes. Tesla and Marconi did some interesting experiments with that [quoted text clipped - 4 lines] > > > >Yes. Tesla even had ideas about supplying power to machines that way. Without a unique definition for the word "electrcity," this discussion makes no sense. > Well, there is no movement of charged particles through the air then. > The form of energy flowing through the air is not electricity but > electromagnetic radiation. In most books the word "electricity" means electrical energy. Or in other words it's 60Hz EM radiation being guided along a 2-wire transmission line. Search google for keywords "KWh of electricity." Then search on "coulombs of electricity." The more common use by far is electricity=energy. Therefore a flow of electricity is *not* an electric current, and a flow of electricity is measured in watts, not amps. > That can even flow through a vacuum where > there are no charged particles, molecules, atoms, or any of the usual > subatomic particles. When electrical energy flows across a circuit from a source to a load, it always flows in the region surrounding the conductors and not inside them. The flow is described by the cross product of the e-field and the b-field outside the wires. Inside the wires the e-field is insignificant, and since the small field is axial, it gives an energy-flow vector which is *inwards.* This makes perfect sense, because wires become warm only because electrical energy is flowing from the surrounding space and into the metal. > As for electricity to flow through air without sparking - that can be > done, although not often practically, and there is a name for that > phenomenon - "ionic current". That's a flow of charge, not a flow of energy or "electricity." Note that scientists have for the most part abandoned use of the word "electricity" to mean charge. Faraday and Maxwell may have used it, but since the early 1900s the textbooks have dropped it. They no longer mention "quantity of electricity" but instead call it "quantity of charge." > In an ionic current, charge is carried by > movement of ions. Where there are ions, there may also be some free > electrons available to move charge. > > Ionic currents are usually less than 1 microamp. Well, it's a current density. So a more appropriate measure would be 1 microamp per square millimeter, or something. If the ion drift is a meter per second, then this implies that a microcoulomb worth of charged air can take the form of a cylinder 1M long and ~1mm in diameter If 1uA/mm^2 were a typical value for non-corona, then we could silently transmit 100uA through a 1cm pipe, or 10mA through a 10cm pipe. Hmmm, sounds a bit large when compared to the current on the belt of a classroom VandeGraaff machine. > They are hard to > target over major distances to anything other than a greatly isolated [quoted text clipped - 8 lines] > conductive - doing that with UV requires wavelengths below 200 nm, maybe > well below (184.9 nm ozone-forming mercury wavelength may not work). Nikola Tesla was putting vacuum bulbs on the top of small Tesla Coils. They produce a fan-shaped visible glowing beam several feet long. Today we would describe this as a pre-ionized path created by x-rays then lit up by a few milliamps of high-freq current. With x-rays involved, we can convert the air into a fluorescent lamp. Use it to light up your bedroom and also light up your internal organs at the same time. What fun! :) ((((((((((((((((((((((( ( ( (o) ) ) ))))))))))))))))))))))) William J. Beaty Research Engineer beaty@chem.washington.edu UW Chem Dept, Bagley Hall RM74 billb@eskimo.com Box 351700, Seattle, WA 98195-1700 ph425-222-5066 http//staff.washington.edu/wbeaty/ In alt.sci.physics.acoustics Radium <glucegen1@excite.com> wrote: > > In alt.sci.physics.acoustics Radium <glucegen1@excite.com> wrote: > > > > > Can electricity flow through air w/out sparking? > > Yes. Tesla and Marconi did some interesting experiments with that > > phenomenon. > You mean they were able to pass electric current through air w/out > arcing, sparking, or coronal discharge? Not precisely. They were, however, able to create an electromagnetic field, which varied at audio frequencies, which was able to pass through the air without arcing, sparking or coronal discharge. Philo Farnsworth built on their work. SignatureA nation of sheep will beget a government of wolves. --Edward R. Murrow > Not precisely. They were, however, able to create an electromagnetic > field, which varied at audio frequencies, which was able to pass through > the air without arcing, sparking or coronal discharge. Philo Farnsworth > built on their work. Didn't the Fane Ionophone used an AF modulated RF discharge to produce a speaker with a very light "cone"? ISTR they needed the quartz-mounted discharge electrode tips replacing every so often. Weren't they mainly used as tweeters? Didn't they need careful shielding to avoid annoying amounts of RFI? A similar "speaking spark" phenomenon is not unheard of close to powerful MW and LW transmitters eg at joints in metal pipes, fences, etc. >In alt.sci.physics.acoustics Radium <glucegen1@excite.com> wrote: > [quoted text clipped - 12 lines] >the air without arcing, sparking or coronal discharge. Philo Farnsworth >built on their work. You are talking about what I think of as capacitive coupling rather than electromagnetic radiation? Yes, that does happen, and is the main mechanism for fluorescent lamps and neon lamps to light up a few feet from a Tesla coil. Source and target are effectively plates of a capacitor, usually a non-ideal capacitor. The air (vacuum also works) is the dielectric. This is normally not an efficient way to move power, although a few exceptions to this could be made as laboratory curiosities - and then optimistically that can transmit power efficiently over a distance maybe the length or the width of the lab, and then probably only to a constant impedance load, and with eficiency still easily exceeded by that of using wire. But with even low efficiency of moving power this way, plenty of audio circuits run into problems with AC line power getting into them that way, and some amplifiers run into trouble with this coupling means transferring a bit of the output to the input. A lot of audio circuits would get easier and a lot of shielding would not be needed if the dielectric constant of air was zero rather than close to 1. However, speed of an electromagnetic wave through a material is C divided by square root of product of permeability and dielectric constant of that material, so it appears to me that air having dielectric constant much below 1 is going to be hard to find! - Don Klipstein (don@misty.com) Each time I see this thread title, I get more upset. Yes! Look up ionization chamber/ Bill In alt.sci.physics.acoustics Don Klipstein <don@manx.misty.com> wrote: > >Not precisely. They were, however, able to create an electromagnetic > >field, which varied at audio frequencies, which was able to pass through > >the air without arcing, sparking or coronal discharge. Philo Farnsworth > >built on their work. > You are talking about what I think of as capacitive coupling rather than > electromagnetic radiation? I'm talking about AM radio - and maybe I'm using terms so loosely that I am using them incorrectly.. SignatureA nation of sheep will beget a government of wolves. --Edward R. Murrow On 9/7/06 3:02 PM, in article edq4t2$bl9$1@reader2.panix.com, > I'm talking about AM radio - and maybe I'm using terms so loosely that I > am using them incorrectly.. I can believe that! Bill -- Ferme le Bush > In alt.sci.physics.acoustics Radium <glucegen1@excite.com> wrote: >>Can electricity flow through air w/out sparkink? HEY; look inside your xerox machine! the fine wires streching across the width if the paper and drum by the paper and he drum. They do it neately and consistently every day! They transfer a charge through the air that lays down a charge onto the drum surface which is then modulated by the light from the copy... the net charge left picks up lampblack (toner) particles which are then transferred to the paper having an opposite charge, also put there by the other fine wire, then baked for presentation. In being forced through the air, driven by several KV, the barging ions also create ozone, which you can often smell around the machine; that ozone not completely absorbed by an ozone filter in the cooling air path. Angelo Campanella. |
Reply to this Message |
 Sign In
 Join
 My Latest Posts My Monitored Threads My Blog My Photo Gallery My Profile My Homepage Start New Thread Enable EMail Alerts Rate this Thread
|
©2009 Advenet LLC Privacy Policy - Terms of Use
This website includes both content owned or controlled by Advenet as well as content owned or controlled by third parties.