A green and clean environment is a human right!
General => General Discussion => Topic started by: Dave on May 07, 2013, 05:59:21 am
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A few weeks ago I finished up quantum mechanics (intro) and started electrostatics and now I'm just about to finish electromagnetism. This is only physics II so I've only scratched the surface of all these things.
For the first time in quantum mechanics and electrostatics I was introduced to an event when energy is created (they think). Its very simple and related to what we're working on.
A charged object has an effect on its surroundings. We all know this from seeing and doing experiments with static electricity and a stream of water. The charged object bends the stream of water but does not lose its charge. How could this be? The electric field is the answer. A static electric field emits photons without discharging and these photons influence the things around it. Work is done for free :)
Photons are the force carrier.
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Nice theory.
But if an atom transmittes energy, then that will not go on forever, or am i wrong here?
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if proton has electron then it will be neutral or discharge to be neutral??static electric only discharge to gound??
thanks
geenee
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Nice theory.
But if an atom transmittes energy, then that will not go on forever, or am i wrong here?
Well it depends what is being transmitted. If I run a current through a gas I will produce a plasma that will emit photons until I remove the power supply. This is because the photons are being emitted when the electrons are moving to a lower energy level. That is what I think your talking about?
Now the awesome part. If i have a charged rod. A rod with a surplus of electrons. The rod cannot discharge without coming in contact with something conductive or at least something it can discharge through. So, if there is air or some other insulator between the charged object and ground or a discharged point it cannot discharge. But, it still has an effect on this objects its near. The photons I talked about are a force carrier, not a transfer of energy.
The photon is the force carrier for the electric force. It is in the upper right corner of the table bellow.
A charged rod will effect on electroscope by polarizing it. The rod is not discharging but for example if the rod was negative it would repel negative charges around it. Electrons in a conductor close bye would move as far away from the rod as possible. This would produce a polarized object. The charges in the influenced conductor will move until they get to a point of electrostatic equilibrium. But nothing is stopping me from applying the same fore to something else without recharging the rod.The rod will eventually discharge but it is not related to the objects it effects as long as it doesn't discharge into it by coming into contact with it. So, i can effect as many objects as I want without effecting the charge of the rod.
The force of the electric field is calculated by E=Kq'/(R squared) and the electric force is calculated between to charged objects by F=Kqq'/(R squared) Everything is in absolute value.
I'm sure you guys have seen these equations before but if anyone needs more info I can explain them further.
Sometimes its hard for me to understand what others are talking about so I understand if I need to explain my points of view better. Just let me know.
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Hello Dave
Actually those are not actual photons being emitted, its said that the electric or magnetic forces acts by exchange of virtual photons.
if you bend the ater stream, its not the electric field that is doing ork its only changing its path. Its the same for a moving charge in magnetic field being used this don't discharge the magnet but the trajectory is bent anyway...
The concept of ork means force applied for a distance... in the case of the stream...
Did you considered this?
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Hello Dave
Actually those are not actual photons being emitted, its said that the electric or magnetic forces acts by exchange of virtual photons.
if you bend the ater stream, its not the electric field that is doing ork its only changing its path. Its the same for a moving charge in magnetic field being used this don't discharge the magnet but the trajectory is bent anyway...
The concept of ork means force applied for a distance... in the case of the stream...
Did you considered this?
Yes the photons are not the same as the one emitted from a bulb or the sun.
But I would not call the force carrying photons virtual. They are bundles of energy or a quanta. So a charged object emits these packets of energy without discharging. This is the part that seems so amazing to me.
In physics, a force is said to do work when it acts on a body so that there is a displacement of the point of application, however small, in the direction of the force. Thus a force does work when it results in movement.
So a change in direction toward the force is still work in my opinion. If an electroscope is charged by the field alone the leaves will repel each other. They both move. Work is done and the object that charged the electroscope still has the same charge.
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well in terms i think your thought is not completely wrong... but i made this same question to many physicists at my university and they convinced me that as the water moves perpendicular to the field force, this is not work since its defined as force times distance times cosine of the angle between the force and the movement. and cosine of 90 is zero.
It could only do work if the water actually goes in the direction of the field and stops there because if it gets away from the field the integral turns to zero, since it does positive and negative work, do you understand?
I agree that it change the direction but the concept of work is that.
Thats why meyer implied the condition for the statement that electric fields does work for free only if the current is restricted...because if the water get in contact to the source its going to discharge the source of field...
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we could argue Well if you could bent a waterfall in such manner as to make the water to take this different path because of the field this mean it won a velocity in the horizontal direction for say, than where this same velocity came from? is the same velocity it has before but just in another direction.... i guess thats why work is zero... to make the water change its path it used the attraction force from the lines of force to reduce the speed in one direction and converting in other direction..
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we could argue Well if you could bent a waterfall in such manner as to make the water to take this different path because of the field this mean it won a velocity in the horizontal direction for say, than where this same velocity came from? is the same velocity it has before but just in another direction.... i guess thats why work is zero... to make the water change its path it used the attraction force from the lines of force to reduce the speed in one direction and converting in other direction..
Thank you for that explanation. I'm not entirely convinced that no work is being performed but cosine of 90 is 0. My own understanding of physics will have to grow before I am satisfied. So maybe in this situation their really isn't any work. I'm wondering if the equation has limitations because its classical physics but I don't know enough to get into that. Anyway, i think the result of no work is specific to the example.
Your explanation did make me wonder if i could find other examples without this limitation I came across this http://physicsworld.com/cws/article/news/2005/jul/26/electric-fields-move-water-droplets
It wasn't exactly what I was expecting but still very interesting! They are using parallel uniform fields to propel the water molecule.
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I have another thought about the water stream experiment. I looked up an illustration of the field lines. If you imagine the the charged object is positive(on the left) and the water is one the right (negative dipole being attracted). It seems to me that the water is moving along the field line for a short time. Since the field lines are the force, the water is traveling parallel along them. So once again I think the work equation holds and cosine is not zero. The water is moving towards the rod along the field lines. The water would stop if it wasn't for gravity.
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You may be aware that there are two kind of electric fields, static and electromagnetic (circular)
what if science discarded a component of these electric fields?
I think i'm discovering how the EPG system work.
If you could use an electric field to acelerate ions they would result in a magnetic field...
Meyer clearly stated that we can indeed use electric fields to perform work if the amps are restricted but what is the meaning of this.
What if you could use the electric field force to sort ions from the air for example?
I had this idea when i tried to think about a sequential ionizer to get millions of volts applied...
when you consider the electric field lines of force you get that positive ions would go in one direction and negative ones in the other direction, but when they arrive at the electrode nothing impeeds it from discharging...
I mean if you had two metallic electrodes the ions can exchange charges with them and consume power and we don't want that.
For example you get plastic tube in form of T, and there air is forced to get in from the middle, and you put an electric field at both exits, but with an insulated electrode not a metallic only... with that you set up an electric field across both exit of gas, well it seems to me that at one side positive ions only should exit and on the other side negative ions... well if you than pass this charged ions into a metallic tube you could collect their electricity right?
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Exactly!!!! :)
In the epg, all we would need is a charged gas or liquid. We can move these with an electric field alone. Since moving charged particles have a magnetic field we could induce a current in a coil.
I've been working on this concept for some time now. Hydrogen might be a good choice to ionize. An electron emitter might do the trick. Really any of the halogens would be some what stable also. One thing I can't figure out is how long the gas would last.
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Meyer clearly stated that we can indeed use electric fields to perform work if the amps are restricted but what is the meaning of this.
What if you could use the electric field force to sort ions from the air for example?
I had this idea when i tried to think about a sequential ionizer to get millions of volts applied...
when you consider the electric field lines of force you get that positive ions would go in one direction and negative ones in the other direction, but when they arrive at the electrode nothing impeeds it from discharging...
I mean if you had two metallic electrodes the ions can exchange charges with them and consume power and we don't want that.
For example you get plastic tube in form of T, and there air is forced to get in from the middle, and you put an electric field at both exits, but with an insulated electrode not a metallic only... with that you set up an electric field across both exit of gas, well it seems to me that at one side positive ions only should exit and on the other side negative ions... well if you than pass this charged ions into a metallic tube you could collect their electricity right?
My post above this one was meant for the first part of your post. I must of mist the rest
Sounds like a great idea! I wonder how many free ions there are in the air. Also, It seems to me that the Ions would stick to the insulated electrodes rather than passing out the end of the tube. So maybe you would have to discharge the field before they would oxidize and reduce with other electrodes to collect their energy?
You have got me thinking about what Stan talks about when he says voltage performing work. It seems to me that no matter how much you restrict amp flow the voltage drop will never be across the cell. If amp flow is restricted, the cell doesn't gain resistance. So it will never act like a true capacitor. What I'm think is that the electrons that move through the water have a lot of energy at a high voltage so there electric field will be strong and have an effect on the water without having a voltage drop. The net effect would be a high energy wave moving through the water with very little power lost to the cells resistance. So, the electric force of the electrons are performing work on the water :) The voltage drop is across the inductors.
Sorry if this is off topic, I guess its still about the electric force performing work.
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The hole in thermodynamics
First I would like to say, sorry for my lengthy absence. School is difficult and boring
I've been pondering electric fields ever since first starting this topic and a few days ago I came across something fascinating.
In my opinion, its ignored by physics because it proves simple laws incorrect and needs a lot of complex math to be proven other wise. That being said, I normally don't ever disagree with math but when it comes to the electric field and work, I just can't help it.
her is a clip from a website. I don't have the image, just imagine a closed loop with a static electric field
Let us now consider the special case where point A is identical with point B. In other words, the case in which we move the charge around a closed loop in the electric field. How much work must we perform in order to achieve this? It is, in fact, possible to prove, using rather high-powered mathematics, that the net work performed when a charge is moved around a closed loop in an electric field generated by fixed charges is zero. However, we do not need to be mathematical geniuses to appreciate that this is a sensible result. Suppose, for the sake of argument, that the net work performed when we take a charge around some closed loop in an electric field is non-zero. In other words, we lose energy every time we take the charge around the loop in one direction, but gain energy every time we take the charge around the loop in the opposite direction. This follows from Eq. (77), because when we switch the direction of circulation around the loop the electric field on the th path segment is unaffected, but, since the charge is moving along the segment in the opposite direction, , and, hence, . Let us choose to move the charge around the loop in the direction in which we gain energy. So, we move the charge once around the loop, and we gain a certain amount of energy in the process. Where does this energy come from? Let us consider the possibilities. Maybe the electric field of the movable charge does negative work on the fixed charges, so that the latter charges lose energy in order to compensate for the energy which we gain? But, the fixed charges cannot move, and so it is impossible to do work on them. Maybe the electric field loses energy in order to compensate for the energy which we gain? (Recall, from the previous section, that there is an energy associated with an electric field which fills space). But, all of the charges (i.e., the fixed charges and the movable charge) are in the same position before and after we take the movable charge around the loop, and so the electric field is the same before and after (since, by Coulomb's law, the electric field only depends on the positions and magnitudes of the charges), and, hence, the energy of the field must be the same before and after. Thus, we have a situation in which we take a charge around a closed loop in an electric field, and gain energy in the process, but nothing loses energy. In other words, the energy appears out of ``thin air,'' which clearly violates the first law of thermodynamics. The only way in which we can avoid this absurd conclusion is if we adopt the following rule:
The work done in taking a charge around a closed loop in an electric field generated by fixed charges is zero.
Hopefully that wasn't to long of a read. anyway, a static field can force and charged particle around a loop continually without performing work or using energy. Net work is zero because it would violate thermodynamics otherwise. Obviously, something is happening for nothing which isn't supposed to happen. According to thermodynamics no work is being done so if you were to harness this movement and create electricity, thermodynamics would not recognize it. Thats my opinion, and its really something cool to think about.
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About that i got a really good for you.
Stan ask the audience:
Didn't the rain drops comes from the water which got heat from the suns energy, than defy the laws of gravity...?
My question is:
Aren't we already using gravity static field reacting with sun heat to generate rain and also energy from this movement?
My question is why it could not be done with an electric field?
I think that if the earth had a bigger mass and rotated little faster there would be rain all nigh long and sun shining every day.
So if we could have a electrically charged rotating globe with some material that under light or heat defy the electric field and when it rotates back to dark it gains energy from the electric field generating power for example "rain in the system".... what could be done? Reinventing Nature? Playing like Gods?
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well you should note however that it would only do no work for a homogeneous electric field, you don't need high powered math since the displacement integral is zero the work is zero very simple... these days I have been working on a system that gets energy out of the E field now the hard stuff is how to get that energy out say you accelerate electrons without energy cost and the total kinetic energy is increased how do you get energy out wihout thermal loses to make overunity?
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4300% energy gain or more.. what am I doing wrong? :P
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well you should note however that it would only do no work for a homogeneous electric field, you don't need high powered math since the displacement integral is zero the work is zero very simple... these days I have been working on a system that gets energy out of the E field now the hard stuff is how to get that energy out say you accelerate electrons without energy cost and the total kinetic energy is increased how do you get energy out wihout thermal loses to make overunity?
yes, only from a uniform electric field. No work being performed is the beauty of it because we still are moving something for nothing.
That is the question! how to get the energy out. The electrons are being accelerated with no energy consumption and since they are in motion they create a magnetic field. But the magnetic field created by the electrons is also uniform so we can't induce a current in a coil. If we can just tweak it enough to create something like a non uniform field we could capture the energy. I have a few ideas but I have not developed them far enough yet
also, I was talking to some guys on a physics forum that work with particle accelerators and apparently they can pick up some rf fields from the accelerated particles in a near by coil.
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ok dave I have figured out how to accelerate them without energy cost but the problem is how to get energy out of the system...or I can just build an x-ray machine that works with a 12V battery ;D
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I like the xray machine idea!!! hahah
I see two different ways to remove energy from the system. But like I said, I'm not finished developing the ideas so I will post after I close the holes in my theories.
Have any ideas?
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I don't care about holes in theories post your ideas I can help.. only thing I can think of now is a pick up coil and to pulse the electrons... I only need to get like 5% of the energy out for this to work.
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Ok, I'll give it a shot. and I agree, from the model I created, we only need to capture a small amount of the magnetic field to make up for the applied electric field.
I'll post back after I'm done with class today and have gathered my thoughts.
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One idea is to pulse the electrons, as you have already stated. It might be possible to group electrons together in packets with space in between each packet. This way the electrons don't need to stop at any point and the field will appear nonuniform. Apparently, creating these packets is common in particle accelerator.
Another idea is to actually try to create a potential across a conductor and try to get the free electrons to flow through it. I mean create a potential by pushing a mass of electrons against one end and forcing electrons away from the other end. So just like any normal circuit except powered by free electrons under the force of an electric field.
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about the second thinking about 2d materials?
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2d materials? Like graphene?
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in monolayer graphene electrons only have one way to go but I'm not sure if classical mechanics applies there, it's complex stuff for me.
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I was planning on creating an electron cloud with an electron emitter from an old tv. I came across a thread on a physics forum where someone stated that these electrons were just part of the circuit and enter back into it when hit the screen. This kind of puts a hole in my plans. Anyone have any good suggestions for creating an electron cloud?
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You would need to confine them like antimatter, you need an electromagnetic bottle...
Of course the electrons need to complete the circuit, so the energy they gained derives from the electric force imposed.
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Hmm ok, I was under the impression they were just released from a heated filament and were actually free electrons.
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The magnetic bottle doesn't work as far as I know because the electrons interact with each other and they escape the magnetic field... when they escape they complete the circuit. I need a vacuum system really... I don't suppose anyone knows about a cheap diffusion pump without much shipping cost to my country? or I need a mig welder to build one..
the simplest configuration is with a capacitor the electric field is easily achieved this way but if the electrons hit the positive plate the ciruit will have made all the work ..the trick is to never hit the positive plate...
with 10kv in cap and initial 100v 4300% energy gain or more!.. with 5% out you have a "COP" of 2// trajectory of the electron is very hard to calculate I wonder how big diameter of a coil will take energy out.. HOW could I extract heat from the system?
Maybe meyer's circle coil thing has similarities..EPG
some precision equipment is needed \\ will write letter to santa for christmass
hint of the day: use magnets
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I was planning on creating an electron cloud with an electron emitter from an old tv. I came across a thread on a physics forum where someone stated that these electrons were just part of the circuit and enter back into it when hit the screen. This kind of puts a hole in my plans. Anyone have any good suggestions for creating an electron cloud?
A cloud of stationary electrons can be produced by sending an electron beam through a couple of nylon threads, around a half inch apart. The nylon causes the beam to stop moving.
I was wondering why we can't take a crt and use an electret for the second anode? Power output would go from the screen electrode, through a load, then back to a cold cathode emitter, which operates on potential only.
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hmmm how does cold cathode emitter doesnt consume power if electrons circulate ?
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hmmm how does cold cathode emitter doesnt consume power if electrons circulate ?
It's based on the virtual photons you guys were talking about. Every time the field emits a virtual photon, it also pulls in a virtual anti photon from the environment. The cold cathode MAY consume a small amount of power, but this should be offset by the gain due to the second anode. The cusped field does the work, and the potential is not consumed, with an electret.
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So you're saying to use a conductive electret for the anode of the emitter?
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An electret might work as part of the emitter, but it would be better to use Farnsworth's multipactor cold cathode because you'd get more electrons to accelerate through the curved part of the tube, with the non conductive electret. The best type of emitter is a thin film diamond layer, like is used in some of the flat panel displays such as plasma screens. These have enough power you don't have to have a vacuum interface for the tunneling effect. But you would have to use Helium or some gas which doesn't form negative ions. Ions can eventually reduce an electret's charge.
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I'm not very familiar with multipactor devices but if the electret's field is used for adding strength to the cathodes how will you control the on/off timing? In these devices there are 2 cathodes 1 anode in the middle and a resonant circuit that controls the potential of the cathodes .. http://journal.borderlands.com/1988/the-farnsworth-multipactor-tube/
this device looks promising... http://en.wikipedia.org/wiki/Electron_multiplier for what I must build