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Post Reply Electromagnetic field in mid air, capacitor
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Posted 10/17/17 , edited 10/17/17
You got a capacitor with two plates, an electric field is formed between the plates when the capacitor is charged. One plate would have positive charge and the other plate would have negative charge. See video below:

https://www.youtube.com/watch?v=wDbKWgKwT5c

How do you move this electric field without moving the capacitor plates? The electric field cannot diminish when you move it away from the charges.


Alternating current, antenna, radio
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Posted 10/17/17 , edited 10/17/17
Just move the plates
Posted 10/17/17 , edited 10/17/17
since electrons are just probabilistic functions, if you wait long enough it will move of it's own accord if you're lucky.
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Posted 10/17/17 , edited 10/17/17

ProfessionalWeaboo wrote:

Just move the plates


No you cannot move the plates, the point is to create a magnetic field in mid air
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Posted 10/17/17 , edited 10/17/17
Are the plates too heavy or something?
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Posted 10/17/17 , edited 10/17/17

ProfessionalWeaboo wrote:

Are the plates too heavy or something?


My bad, the point is to create an electromagnetic field in mid air. I used a capacitor to facilitate the understanding.

P.S Just drag it out of the body, darn it I think Lorreen figured this out
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Posted 10/17/17 , edited 10/17/17
moving the 'electric field' is equivalent to moving the total charge - i.e. the electrons. This is simply a case of creating any circuit after switching away the earth connection equivalent which built up the positive charge on one plate.
The electrons which make up the electrical field then flow through the circuit to balance out the difference in electrical potential energy, just as if the capacitor were a battery with one plate representing each terminal, -ve & +ve.
For example, the circuit could include other capacitors which become charged up with their own respective electrical fields to balance out the electrical potential.
Recharging the initial capacitor is then simply a matter of deswitching that circuit back to the original setting which enabled the buildup of charge.

Note the assumption of 'earth' in that video simply means there is a null electrical potential at the earth terminal, which is not always true during electrical storms.

It is more useful in a real world example application to think of that earth terminal as the positive terminal (anode) of a dynamo generator (via diodes to enforce directional electron flow), and the negative terminal (cathode) of the capacitor connected in circuit to the negative terminal of the generator. Remember these connections are switchable to/from capacitor charge/discharge state.
e.g.
http://www.instructables.com/id/How-to-charge-a-super-capacitor-using-a-hand-crank/

After re-reading your latest post on 'the point is to make a movable electrical field in mid air',
I think you may need to look more closely at the real world physics of capacitors, as the air-gap between the charged plates is incredibly small, and the charge is proportional to the surface area of the plate.

If you want to work on creating a large ionised (charged particle) field which can then act to support moving/floating objects within that field, look at this instead:
https://en.wikipedia.org/wiki/Ionocraft
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Posted 10/17/17 , edited 10/17/17

morte111 wrote:

moving the 'electric field' is equivalent to moving the total charge - i.e. the electrons. This is simply a case of creating any circuit after switching away the earth connection equivalent which built up the positive charge on one plate.
The electrons which make up the electrical field then flow through the circuit to balance out the difference in electrical potential energy, just as if the capacitor were a battery with one plate representing each terminal, -ve & +ve.
For example, the circuit could include other capacitors which become charged up with their own respective electrical fields to balance out the electrical potential.
Recharging the initial capacitor is then simply a matter of deswitching that circuit back to the original setting which enabled the buildup of charge.

Note the assumption of 'earth' in that video simply means there is a null electrical potential at the earth terminal, which is not always true during electrical storms.

It is more useful in a real world example application to think of that earth terminal as the positive terminal (anode) of a dynamo generator (via diodes to enforce directional electron flow), and the negative terminal (cathode) of the capacitor connected in circuit to the negative terminal of the generator. Remember these connections are switchable to/from capacitor charge/discharge state.
e.g.
http://www.instructables.com/id/How-to-charge-a-super-capacitor-using-a-hand-crank/

After re-reading your latest post on 'the point is to make a movable electrical field in mid air',
I think you may need to look more closely at the real world physics of capacitors, as the air-gap between the charged plates is incredibly small, and the charge is proportional to the surface area of the plate.

If you want to work on creating a large ionised (charged particle) field which can then act to support moving/floating objects within that field, look at this instead:
https://en.wikipedia.org/wiki/Ionocraft


Right, I am not making the objects float. I am theorizing about creating an electromagnetic field, without any medium, in mid air. Like lightning, except it's more subtle. I heard you can create an electromagnetic field in mid air or some distance away with a really powerful generator. I don't need a powerful electromagnetic field in mid air, but I need a complex moving electromagnetic field in mid air.

P.S I am saying electromagnetic field because I am not sure if it is electric field or magnetic field I need. I think it is electric field.
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Posted 10/17/17 , edited 10/17/17
It has been awhile since I dabbled in this but lets give it a shot. So if your goal is to create a field similar to lightning (electric field) in mid air, you should ionize the air away from the plates in the direction you want the field to move. As long as you keep moving the location of ionized particles, the field itself will naturally keep moving. The generator you mentioned should does this to a certain effect.
As I said before, it has been since my college days since I dealt with EM fields, but I believe that was true...
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Posted 10/17/17 , edited 10/17/17

TheDimmLight wrote:

It has been awhile since I dabbled in this but lets give it a shot. So if your goal is to create a field similar to lightning (electric field) in mid air, you should ionize the air away from the plates in the direction you want the field to move. As long as you keep moving the location of ionized particles, the field itself will naturally keep moving. The generator you mentioned should does this to a certain effect.
As I said before, it has been since my college days since I dealt with EM fields, but I believe that was true...


Ya, that caught up to Halloween season >.<. You'll need to piece together one trillion laser dots for this one though, I'm theorizing the brain's moving circuitry in mid air.

https://www.youtube.com/watch?v=KfVS-npfVuY

P.S I've always imagined you could just build and shape a brain like magnetic field in mid air with a powerful magnetic field generator, I could be wrong. Piecing together one trillion lasers would be hard, but it is progress . That does seem doable, man you're good.....
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Posted 10/17/17 , edited 10/17/17
Keeping things simple, electric and magnetic fields arise from sources: things that possess electric charge (like protons and electrons) produce electric fields, and electric currents produce magnetic fields. It is the nature of fields that they extend throughout all space - though if you get far enough away from the source, normally the field gets really weak, with its magnitude approaching zero. The electric field produced by stationary charges actually acts just like gravity - its strength and direction behave the same way, though electric fields are much stronger than gravitational fields. The reason gravity is so strong on the earth is that the earth is really massive (its gravitational "charge" is big, because it contains so much matter). We're used to electricity and magnetism being weaker because, in reality, those forces are so strong that matter arranges itself so they cancel: hence electrons orbiting around nuclei containing the same number of protons, so that the net charge of an atom is zero (unless you remove electrons or add protons to it). As a whole, the earth is basically electrically neutral, but there can be local changes in charge density; that's exactly what a capacitor is for - it's a device to hold charge so it doesn't spread out.

The first thing you ask for - an electric field with the same value as that of a capacitor, except without the plates - is impossible. The plates are there to hold the charge, because as I said, electric fields require sources. If you have some other way to suspend the charges in space, fine, but then that's a capacitor. If the charges just sit there with nothing holding them in place, they'll automatically fly towards each other - because the charges attract and repel each other. If you know a little math, you can show that it's impossible for free electric charges simply to sit in equilibrium held by electric fields alone. What your video of a capacitor doesn't show is that capacitor plates can't just sit freely: if they're not stuck to something else, they'll fly towards each other if they possess opposite charges.

Your clarifications - that you want something "like lightning, except it's more subtle", and that "you can create an electromagnetic field in mid air or some distance away with a really powerful generator" don't really help you here. Lightning occurs because charge builds up in the sky - friction due to wind and whatnot rips electrons off of atoms. The situation is exactly like that of the capacitor: in the sky there is a lot of negative charge, and this creates a buildup of positive charge on the surface of the ground (because the negative charge attracts it). The electric field isn't produced by the lightning; the electric field is already there. Lightning occurs because the electric field is so strong that it rips the electrons off the atoms in the air. The electrons from the sky can then move through the line of ionized atoms to the ground. Ripping atoms apart conveying a huge current generates a lot of light and sound, and that's what lightning is. (Or, at least, that's the simple version; perhaps there are more complicated things going on, but that is the broad theoretical explanation.) So you actually have a capacitor when there's lightning: the plates are the sky and the ground. It doesn't make sense to say the lightning is just "mid air".

I don't know what you mean by "a really powerful generator"; you can't just have free-floating electric fields without sources. And if the electric field is in air, if it's too strong it'll make sparks through the air, decreasing the field strength (because the charge left your source through the spark). Magnetic fields are different, but again, they require sources. You can't have a constant magnetic field without a source, and while I'm not sure (I've never thought about it), I imagine there is a similar limit to the maximum sustainable magnetic field in air.

Now, what you can do is this: there is a particular arrangement of moving electric and magnetic fields that can exist and move along far away from its source. That is what light is.

Unfortunately, "theorizing the brain's moving circuitry in mid air" is nonsense. I don't know what you're trying to do, but thinking about science like this almost never works. Go pick up a textbook, as even a middle-school-level understanding of electricity is enough to see that what you said about lightning is wrong.
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Posted 10/17/17 , edited 10/17/17

auroraloose wrote:

If you have some other way to suspend the charges in space, fine


If you check out the second video I posted, they are able to ionize air to create plasma in mid air by focusing laser. Now does plasma equal capacitor? I dunno if that is the case by Resident Evil's standards . But anyhow I haven't found a better method than creating plasma in mid air, you're free to improve the mechanism
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Posted 10/17/17 , edited 10/17/17
You can trap a plasma with a magnetic field. The sun does it all the time. To get a magnetic field you need moving charges (i.e. electricity in electromagnet) or a permanent magnet with trapped spin vectors.

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Posted 10/17/17 , edited 10/17/17

kiltmaker2 wrote:

You can trap a plasma with a magnetic field. The sun does it all the time. To get a magnetic field you need moving charges (i.e. electricity in electromagnet) or a permanent magnet with trapped spin vectors.



I just need an altering electric field or magnetic field in mid air. There's radio wave, we don't see it, but it's there. Auroraloose wasn't seeing the brain circuitry as charges and fields, but if she does the brain muscle could be easily left out leaving just the charges and fields.

Recreating such charges and fields in mid air is not an easy feat. Telling the charges where to go etc as Aurora loose mentioned. But since we got radio wave, it is entirely possible to create alternating current in mid air. Just that it needs to stay in one place and shape like a brain
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Posted 10/17/17 , edited 10/17/17

fredreload wrote:


auroraloose wrote:

If you have some other way to suspend the charges in space, fine


If you check out the second video I posted, they are able to ionize air to create plasma in mid air by focusing laser. Now does plasma equal capacitor? I dunno if that is the case by Resident Evil's standards . But anyhow I haven't found a better method than creating plasma in mid air, you're free to improve the mechanism


Now that I think about it, what you're doing only really makes sense if you're making a joke about how the thing you're asking for (electric fields without capacitor plates) is really just light. Except the electromagnetic fields of light aren't like those of the capacitor, because the capacitor has a static, constant field (away from the plates' edges), and light does not. You're correct that you can suspend charges in space if you also use magnetic fields, but then you don't have the electric field of a capacitor just floating in midair.
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