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Thread: What is electric charge?

  1. #1 What is electric charge? 
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    Someone explained to me the other day that in an electronic circuit the electrons 'drift' while the charge is moving. I was also told that the electrons themselves do not move.

    What then is charge? Can it be explained as a particle, if so which? If not, what is it (in the context of an electronic circuit)?

    Thanks in advance for any help.


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    Quote Originally Posted by fatman57 View Post
    Someone explained to me the other day that in an electronic circuit the electrons 'drift' while the charge is moving. I was also told that the electrons themselves do not move.

    What then is charge? Can it be explained as a particle, if so which? If not, what is it (in the context of an electronic circuit)?

    Thanks in advance for any help.
    I'm sorry that you have been the victim of a well-intentioned, but badly mangled explanation.

    It is indeed true that there is something that "drifts" along a wire; the average velocity of electrons in a typical circuit is very, very much below the velocity of light. It is not unusual for that drift velocity to be below that of a typical walking velocity for a tired human.

    So when we speak of electromagnetic signals propagating along wires at near the speed of light, we can't be talking about those drifting electrons. That seems to set up a paradox, since signals travel much faster than the electrons.

    The resolution is that the electrons aren't directly carrying the signals. They're involved, to be sure, but by supporting the propagation of a wave. A common analogy invokes a tube full of marbles. You push on one on this end, and "instantly" a marble pops out of the other end. But the marbles in the middle do not move at a high velocity; they barely move at all. The marbles are involved in conveying a signal, but the marbles themselves aren't the signal. And so it is with electrons and electrical signals.


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    Quote Originally Posted by tk421 View Post
    Quote Originally Posted by fatman57 View Post
    Someone explained to me the other day that in an electronic circuit the electrons 'drift' while the charge is moving. I was also told that the electrons themselves do not move.

    What then is charge? Can it be explained as a particle, if so which? If not, what is it (in the context of an electronic circuit)?

    Thanks in advance for any help.
    I'm sorry that you have been the victim of a well-intentioned, but badly mangled explanation.

    It is indeed true that there is something that "drifts" along a wire; the average velocity of electrons in a typical circuit is very, very much below the velocity of light. It is not unusual for that drift velocity to be below that of a typical walking velocity for a tired human.

    So when we speak of electromagnetic signals propagating along wires at near the speed of light, we can't be talking about those drifting electrons. That seems to set up a paradox, since signals travel much faster than the electrons.

    The resolution is that the electrons aren't directly carrying the signals. They're involved, to be sure, but by supporting the propagation of a wave. A common analogy invokes a tube full of marbles. You push on one on this end, and "instantly" a marble pops out of the other end. But the marbles in the middle do not move at a high velocity; they barely move at all. The marbles are involved in conveying a signal, but the marbles themselves aren't the signal. And so it is with electrons and electrical signals.
    You are always so good about explaining things!!! Even though this was not to me, thank you!
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    Quote Originally Posted by babe View Post
    You are always so good about explaining things!!! Even though this was not to me, thank you!
    You are much too kind, babe!
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    Quote Originally Posted by tk421 View Post
    Quote Originally Posted by babe View Post
    You are always so good about explaining things!!! Even though this was not to me, thank you!
    You are much too kind, babe!
    Nope, just being honest.
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    Quote Originally Posted by fatman57 View Post
    I was also told that the electrons themselves do not move.
    In a alternating current circuit, the electrons sit there wiggling back and forth without going anywhere. Maybe that's what they meant by this.
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    Quote Originally Posted by Harold14370 View Post
    Quote Originally Posted by fatman57 View Post
    I was also told that the electrons themselves do not move.
    In a alternating current circuit, the electrons sit there wiggling back and forth without going anywhere. Maybe that's what they meant by this.
    Another very informative person in this forum. Thank you also for that information. I had NO idea that electrons only wiggled....always thought they moved more extensively!
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    Quote Originally Posted by tk421 View Post
    Quote Originally Posted by babe View Post
    You are always so good about explaining things!!! Even though this was not to me, thank you!
    You are much too kind, babe!
    No, she's just much too over-demonstrative and just possibly much too oversexed.
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    Quote Originally Posted by John Galt View Post
    Quote Originally Posted by tk421 View Post
    Quote Originally Posted by babe View Post
    You are always so good about explaining things!!! Even though this was not to me, thank you!
    You are much too kind, babe!
    No, she's just much too over-demonstrative and just possibly much too oversexed.
    Sir John Galt, when doing theatre, one learns to be demonstrative...movements, words, sounds, expressions (but no mugging) are LARGE.....the back of the house has to see what the front of the house sees. *chuckle* and I have been oversexed all my life and I am certainly NOT ashamed of it. I am also smart. I know that is hard to believe. *chuckle* oh and just for you as and I did to Lord Ming, WHACK only I don't have the pan in my hand. ANGELIC Theater is also physical in presentation! bigger ANGELIC the appearance of the whack is there.....but I certainly didn't really hit him!
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    And Sir John Galt, I hope you know that was all in humor.
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    Quote Originally Posted by babe View Post
    Sir John Galt, when doing theatre, one learns to be demonstrative...movements, words, sounds, expressions (but no mugging) are LARGE.....the back of the house has to see what the front of the house sees. *chuckle*
    In less than two hours time I go "on stage" for nine hours, teaching a class of twenty two assorted engineers about vibration. Although that time is interspersed with practical exercises, tests and breaks I am still on, as a solo performer for much of the time. And I'm also the scriptwriter, stage manager, director and producer. So, I too have learnt to be demonstrative and energetic and alive, or passive, introspective and to take on a dozen characters in sequence, to display amazement, satisfaction, bewilderment and more besides. Anything to keep the audience engaged. And - incredibly - I do all this without the benefit of makeup!
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    Quote Originally Posted by John Galt View Post
    Quote Originally Posted by babe View Post
    Sir John Galt, when doing theatre, one learns to be demonstrative...movements, words, sounds, expressions (but no mugging) are LARGE.....the back of the house has to see what the front of the house sees. *chuckle*
    In less than two hours time I go "on stage" for nine hours, teaching a class of twenty two assorted engineers about vibration. Although that time is interspersed with practical exercises, tests and breaks I am still on, as a solo performer for much of the time. And I'm also the scriptwriter, stage manager, director and producer. So, I too have learnt to be demonstrative and energetic and alive, or passive, introspective and to take on a dozen characters in sequence, to display amazement, satisfaction, bewilderment and more besides. Anything to keep the audience engaged. And - incredibly - I do all this without the benefit of makeup!
    *Patting your head*....It's ok...I can teach you! Our "houses" are different, of course. Mine is usually around 300 people....I am there to take them to another place, and let their imaginations flow......I, unlike you, am not teaching Science. I admire and respect what you do. I really do need to help you with the makeup, though. Lights in classrooms are ghastly!
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    I don't know if fatman 57 feels edified as to the standard quantum-theory explanation of "movement" of charge in an electric wire, but there is also an ether-theory model for this question he might want to listen to. -This model views the current as consisting of conduction of charge along the wire not by motion of discrete quantum "particles" (electrons), but as instantaneous resonation of elementary energic units. The mecanism of resonance is vibrational and it involves elementary ether-scale units. All the resonance occurs between these units which are much smaller in size scale than "electrons," which are really merely quantum-size "particle capacity" units formed via aggregational resonance of the elemental units. -A magnetic field represents a side-resonance effect in space to balance the "artificial" situation in which a wire is used to conduct the current. The magnetic field comprises mainly indentical elemental ether energic units which are also in resonance with the ether units inside the wire and traveling from one end (pole) to the other. -It can be appreciated that this is a simpler more rational and unifying model than the quantum mechanical model.
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    People should not post on forum when the are so high.
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    Quote Originally Posted by Michael Anteski View Post
    but there is also an ether-theory model for this question
    No there isn't. One can tell because you made up most of those words: they don't mean anything. Please stop posting nonsense.
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    Quote Originally Posted by Michael Anteski View Post
    I don't know if fatman 57 feels edified as to the standard quantum-theory explanation of "movement" of charge in an electric wire, but there is also an ether-theory model for this question he might want to listen to. -This model views the current as consisting of conduction of charge along the wire not by motion of discrete quantum "particles" (electrons), but as instantaneous resonation of elementary energic units. The mecanism of resonance is vibrational and it involves elementary ether-scale units. All the resonance occurs between these units which are much smaller in size scale than "electrons," which are really merely quantum-size "particle capacity" units formed via aggregational resonance of the elemental units. -A magnetic field represents a side-resonance effect in space to balance the "artificial" situation in which a wire is used to conduct the current. The magnetic field comprises mainly indentical elemental ether energic units which are also in resonance with the ether units inside the wire and traveling from one end (pole) to the other. -It can be appreciated that this is a simpler more rational and unifying model than the quantum mechanical model.
    MODERATOR WARNING : Michael Anteski, you have already been told previously to not post your fringe ideas into the main physics section, yet you persist in doing so. If you have a hypothesis to present, please do so in a separate thread in the appropriate section, i.e. New Ideas and Hypotheses. Consider this an official warning - next time I find your ether ideas in the main physics section, you will be send off on a holiday.
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    Quote Originally Posted by John Galt View Post
    Quote Originally Posted by babe View Post
    Sir John Galt, when doing theatre, one learns to be demonstrative...movements, words, sounds, expressions (but no mugging) are LARGE.....the back of the house has to see what the front of the house sees. *chuckle*
    In less than two hours time I go "on stage" for nine hours, teaching a class of twenty two assorted engineers about vibration. Although that time is interspersed with practical exercises, tests and breaks I am still on, as a solo performer for much of the time. And I'm also the scriptwriter, stage manager, director and producer. So, I too have learnt to be demonstrative and energetic and alive, or passive, introspective and to take on a dozen characters in sequence, to display amazement, satisfaction, bewilderment and more besides. Anything to keep the audience engaged. And - incredibly - I do all this without the benefit of makeup!
    I re-read this. TO do what I do....you study for about 6 weeks...50 pages or more....my largest was 78 pages in the show and I was on 77 of them..then they take all your material away, and it has to be memorized verbatum. You have no guide, no notes nothing..no references to help you should you need ..you are dead alone in front of 300 people. During that process, you learn your blocking...where to stand......you also have to find your character, and develop it to your director's acceptance, and if you say a line they don't like, you have to reprocess, and if you leave one word out.....you are told to fix it. Then there are props, which you don't get till the last week, which you have to learn to use and place..and after you have your tech, and sound (if warranted), and your lighting so you find your light, and you have to make sure you don't portray this to the audience when you perform. This is just a play....add musical, then there is the score to learn, harmony, individual solo's and choreography. You have costume changes (total) that you need to achieve in 30 seconds. am I MODEST? NO! You drop your clothes and get back on stage... You rehearse for 4 hours, and then you rehearse at home every day for at least an hour or so....you rehearse in your car, driving.....with tapes, one show I did as a favor I slept with ear plugs with a tape recorder on because the entire process was 3 weeks and the line load was heavy.....you have not just one component, you have many. Come hell week, you live at the theatre....pretty much, making sure everything is perfect. Then you open the show. You still run your lines, you music, your choreography at home, and you are at the theatre at 6:00 for call, then have warm ups, makeup, costume, and by the time you get out it is 11:00 and you are wound up like a top. SO then you drive home and unwind....run the show again....always looking for something you missed, or can do better. I TOTALLY RESPECT what you do. DO NOT misunderstand me, but what I do is also very demanding. When the run is over. You start all over again. The material is totally different, as is everything else, and you start from square one. I have taught voice. I don't enjoy it. I don't do it anymore. I respect the preparations, the knowledge, the time and research involved in doing what you do. I RESPECT it. Please respect mine. I will also be happy to help you with your makeup, but under fluorescent lighting....it's rather difficult.!
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    Quote Originally Posted by tk421 View Post
    Quote Originally Posted by fatman57 View Post
    Someone explained to me the other day that in an electronic circuit the electrons 'drift' while the charge is moving. I was also told that the electrons themselves do not move.

    What then is charge? Can it be explained as a particle, if so which? If not, what is it (in the context of an electronic circuit)?

    Thanks in advance for any help.
    I'm sorry that you have been the victim of a well-intentioned, but badly mangled explanation.

    It is indeed true that there is something that "drifts" along a wire; the average velocity of electrons in a typical circuit is very, very much below the velocity of light. It is not unusual for that drift velocity to be below that of a typical walking velocity for a tired human.

    So when we speak of electromagnetic signals propagating along wires at near the speed of light, we can't be talking about those drifting electrons. That seems to set up a paradox, since signals travel much faster than the electrons.

    The resolution is that the electrons aren't directly carrying the signals. They're involved, to be sure, but by supporting the propagation of a wave. A common analogy invokes a tube full of marbles. You push on one on this end, and "instantly" a marble pops out of the other end. But the marbles in the middle do not move at a high velocity; they barely move at all. The marbles are involved in conveying a signal, but the marbles themselves aren't the signal. And so it is with electrons and electrical signals.
    Thanks for the replies all!

    It does help, plus Harolds post for AC, but still doesn't tell me what a charge is.

    If it is like a tube of marbles and since I use electrons to push through (DC) then the pipe will always be full or marbles no matter what. But my question is more because as far as I know electrons are negatively charged and protons positively charged - how does the charge actually get transferred though the wire?

    I like a particle theory to explain things (even though not everything can be explained in this way), the mechanics of charge being transferred in this case eludes me...unless it is simply a wave (it was explained to me that waves in the ocean do not involve the forward movement of water atoms which stay still, simply move up and down and that is the wave?).
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    Quote Originally Posted by Strange View Post
    Quote Originally Posted by Michael Anteski View Post
    but there is also an ether-theory model for this question
    No there isn't. One can tell because you made up most of those words: they don't mean anything. Please stop posting nonsense.
    Once more, exchemist's theory holds true: Alternative/New Age woo-woo loves unspecified "energy" and "vibrations" (Man).
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    Quote Originally Posted by fatman57 View Post
    I like a particle theory to explain things (even though not everything can be explained in this way), the mechanics of charge being transferred in this case eludes me...
    If the marbles in a tube analogy didn't help, it may help to know that electrons in a conductor are not tightly bound to their atoms (the protons) they exist in a continuous range of energy levels so they can almost be thought of as a fluid. So, perhaps a hose pipe analogy is better. When you turn on a hose pipe, the water at the other end starts flowing almost immediately (after a time determined by the speed of sound in the hose) even though it may take minutes for a particular water molecule to make its way through.

    Similarly, you get charge flowing out of the wire after a short delay (the speed of light in the conductor - ish) even though individual electrons move more slowly.

    You can even set up an AW (alternating water) system where you get a flow of water out of each end in turn even though the average position of most water molecules doesn't change.
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    Quote Originally Posted by Strange View Post
    Quote Originally Posted by fatman57 View Post
    I like a particle theory to explain things (even though not everything can be explained in this way), the mechanics of charge being transferred in this case eludes me...
    If the marbles in a tube analogy didn't help, it may help to know that electrons in a conductor are not tightly bound to their atoms (the protons) they exist in a continuous range of energy levels so they can almost be thought of as a fluid. So, perhaps a hose pipe analogy is better. When you turn on a hose pipe, the water at the other end starts flowing almost immediately (after a time determined by the speed of sound in the hose) even though it may take minutes for a particular water molecule to make its way through.

    Similarly, you get charge flowing out of the wire after a short delay (the speed of light in the conductor - ish) even though individual electrons move more slowly.

    You can even set up an AW (alternating water) system where you get a flow of water out of each end in turn even though the average position of most water molecules doesn't change.
    That helps!

    Just to confirm, so even though the flow of electrons is slower than light, in a DC setup they are still entered at the input part and flow out at the output part?

    Followup - is charge determined by an electron being in a shell or not - ie will they move from atom to atom at various shell states and the lack or increase of electrons in a shell determine if there is a positive or negative charge present in the locality of the atom?
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    Quote Originally Posted by fatman57 View Post
    Quote Originally Posted by Strange View Post
    Quote Originally Posted by fatman57 View Post
    I like a particle theory to explain things (even though not everything can be explained in this way), the mechanics of charge being transferred in this case eludes me...
    If the marbles in a tube analogy didn't help, it may help to know that electrons in a conductor are not tightly bound to their atoms (the protons) they exist in a continuous range of energy levels so they can almost be thought of as a fluid. So, perhaps a hose pipe analogy is better. When you turn on a hose pipe, the water at the other end starts flowing almost immediately (after a time determined by the speed of sound in the hose) even though it may take minutes for a particular water molecule to make its way through.

    Similarly, you get charge flowing out of the wire after a short delay (the speed of light in the conductor - ish) even though individual electrons move more slowly.

    You can even set up an AW (alternating water) system where you get a flow of water out of each end in turn even though the average position of most water molecules doesn't change.
    That helps!

    Just to confirm, so even though the flow of electrons is slower than light, in a DC setup they are still entered at the input part and flow out at the output part?

    Followup - is charge determined by an electron being in a shell or not - ie will they move from atom to atom at various shell states and the lack or increase of electrons in a shell determine if there is a positive or negative charge present in the locality of the atom?
    In a conductor (for example a metal) the outermost electron shells overlap with a continuum energy state that is delocalised throughout the metal. The outermost electrons can thus cease to "belong" to any particular atom and can wander from one to the next without much impediment (though there's still a little bit, which is what produces electrical resistance.) People speak of the "conduction band" to describe this continuum state. The presence of a conduction band whose lowest energy level overlaps with that of the valence shell energies is the distinguishing feature of a material that is a conductor of electricity. In semi-conductors there is a small energy gap (called the "band gap") between the valence electrons and the delocalised conduction band, so the electrons have to be given a kick up before they can conduct. The way the "kick up" is administered can often be controlled, in order to turn these materials from a non-conducting to a conducting state and back, in a controlled way. In an insulator the conduction band is so far above the valence energies that ordinary processes cannot make the electrons jump up to it, so they do not conduct.
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    Quote Originally Posted by fatman57 View Post

    If it is like a tube of marbles and since I use electrons to push through (DC) then the pipe will always be full or marbles no matter what. But my question is more because as far as I know electrons are negatively charged and protons positively charged - how does the charge actually get transferred though the wire?
    There isn't any net charge that gets transferred. The electrons flow out of the battery from the negative terminal and back in at the positive terminal.
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    Quote Originally Posted by Markus Hanke View Post
    Quote Originally Posted by Michael Anteski View Post
    I don't know if fatman 57 feels edified as to the standard quantum-theory explanation of "movement" of charge in an electric wire, but there is also an ether-theory model for this question he might want to listen to. -This model views the current as consisting of conduction of charge along the wire not by motion of discrete quantum "particles" (electrons), but as instantaneous resonation of elementary energic units. The mecanism of resonance is vibrational and it involves elementary ether-scale units. All the resonance occurs between these units which are much smaller in size scale than "electrons," which are really merely quantum-size "particle capacity" units formed via aggregational resonance of the elemental units. -A magnetic field represents a side-resonance effect in space to balance the "artificial" situation in which a wire is used to conduct the current. The magnetic field comprises mainly indentical elemental ether energic units which are also in resonance with the ether units inside the wire and traveling from one end (pole) to the other. -It can be appreciated that this is a simpler more rational and unifying model than the quantum mechanical model.
    MODERATOR WARNING : Michael Anteski, you have already been told previously to not post your fringe ideas into the main physics section, yet you persist in doing so. If you have a hypothesis to present, please do so in a separate thread in the appropriate section, i.e. New Ideas and Hypotheses. Consider this an official warning - next time I find your ether ideas in the main physics section, you will be send off on a holiday.
    As I have fully described my ether model in previous posts, I considered this last one an addendum. I don't plan any more posts here inasmuch as all I was really interested in was finding a sponsor with deep pockets to fund a field test I propose to prove an ether exists (I have also mentioned that test here before.) I believe there could be a fringe benefit if ether energy is produced. -I realize quantum theorists will probably only recognize a test demonstrating the ether exists.
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    Quote Originally Posted by Michael Anteski View Post
    Quote Originally Posted by Markus Hanke View Post
    Quote Originally Posted by Michael Anteski View Post
    I don't know if fatman 57 feels edified as to the standard quantum-theory explanation of "movement" of charge in an electric wire, but there is also an ether-theory model for this question he might want to listen to. -This model views the current as consisting of conduction of charge along the wire not by motion of discrete quantum "particles" (electrons), but as instantaneous resonation of elementary energic units. The mecanism of resonance is vibrational and it involves elementary ether-scale units. All the resonance occurs between these units which are much smaller in size scale than "electrons," which are really merely quantum-size "particle capacity" units formed via aggregational resonance of the elemental units. -A magnetic field represents a side-resonance effect in space to balance the "artificial" situation in which a wire is used to conduct the current. The magnetic field comprises mainly indentical elemental ether energic units which are also in resonance with the ether units inside the wire and traveling from one end (pole) to the other. -It can be appreciated that this is a simpler more rational and unifying model than the quantum mechanical model.
    MODERATOR WARNING : Michael Anteski, you have already been told previously to not post your fringe ideas into the main physics section, yet you persist in doing so. If you have a hypothesis to present, please do so in a separate thread in the appropriate section, i.e. New Ideas and Hypotheses. Consider this an official warning - next time I find your ether ideas in the main physics section, you will be send off on a holiday.
    As I have fully described my ether model in previous posts, I considered this last one an addendum. I don't plan any more posts here inasmuch as all I was really interested in was finding a sponsor with deep pockets to fund a field test I propose to prove an ether exists (I have also mentioned that test here before.) I believe there could be a fringe benefit if ether energy is produced. -I realize quantum theorists will probably only recognize a test demonstrating the ether exists.
    As far as I am aware the standard model is a preferred one to choose for many reasons. If this ether theory is not proved then maybe the moderators are correct in requesting it be discussed elsewhere. I am searching for a proven answer if possible. I like hearing about what else is going around though, so appreciate the input.


    @exchemist - thanks, a description about the valence shells is exactly what I am looking for. I would like to be able to visualize what is going on in there...

    @Harold - I can now sleep well thinking it is electron flow again, an electrician I spoke to talked more of the charges and said the electrons themselves didn't move, or at least not much. In an AC environment that would be understandable, but DC as far as I currently have it is a linear flow.
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    No, she's just much too over-demonstrative and just possibly much too oversexed.
    teaching a class of twenty two assorted engineers about vibration
    Ahh...the jokes just write themselves!
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    Quote Originally Posted by fatman57 View Post
    Quote Originally Posted by Michael Anteski View Post
    Quote Originally Posted by Markus Hanke View Post
    Quote Originally Posted by Michael Anteski View Post
    I don't know if fatman 57 feels edified as to the standard quantum-theory explanation of "movement" of charge in an electric wire, but there is also an ether-theory model for this question he might want to listen to. -This model views the current as consisting of conduction of charge along the wire not by motion of discrete quantum "particles" (electrons), but as instantaneous resonation of elementary energic units. The mecanism of resonance is vibrational and it involves elementary ether-scale units. All the resonance occurs between these units which are much smaller in size scale than "electrons," which are really merely quantum-size "particle capacity" units formed via aggregational resonance of the elemental units. -A magnetic field represents a side-resonance effect in space to balance the "artificial" situation in which a wire is used to conduct the current. The magnetic field comprises mainly indentical elemental ether energic units which are also in resonance with the ether units inside the wire and traveling from one end (pole) to the other. -It can be appreciated that this is a simpler more rational and unifying model than the quantum mechanical model.
    MODERATOR WARNING : Michael Anteski, you have already been told previously to not post your fringe ideas into the main physics section, yet you persist in doing so. If you have a hypothesis to present, please do so in a separate thread in the appropriate section, i.e. New Ideas and Hypotheses. Consider this an official warning - next time I find your ether ideas in the main physics section, you will be send off on a holiday.
    As I have fully described my ether model in previous posts, I considered this last one an addendum. I don't plan any more posts here inasmuch as all I was really interested in was finding a sponsor with deep pockets to fund a field test I propose to prove an ether exists (I have also mentioned that test here before.) I believe there could be a fringe benefit if ether energy is produced. -I realize quantum theorists will probably only recognize a test demonstrating the ether exists.
    As far as I am aware the standard model is a preferred one to choose for many reasons. If this ether theory is not proved then maybe the moderators are correct in requesting it be discussed elsewhere. I am searching for a proven answer if possible. I like hearing about what else is going around though, so appreciate the input.


    @exchemist - thanks, a description about the valence shells is exactly what I am looking for. I would like to be able to visualize what is going on in there...

    @Harold - I can now sleep well thinking it is electron flow again, an electrician I spoke to talked more of the charges and said the electrons themselves didn't move, or at least not much. In an AC environment that would be understandable, but DC as far as I currently have it is a linear flow.
    OK. Let me try. When you have several atoms together, the individual atomic orbitals in the outermost ("valence") shells can merge to form new sets of multi-centre orbitals, with a wider range of energies than are present in isolated atoms. These will be filled up with electrons, starting from the lowest energy states, until all the electrons required for electrical neutrality are in. (This is something called the Aufbau Principle). The higher energy ones will remain empty unless an electron is excited (given more energy) enough to jump into one.

    In the case of individual molecules, these multi-centre orbitals are called "molecular orbitals" and are the theoretical basis of chemical covalent bonding. In the case of an extended (pseudo-infinite) array of atoms, such as you get in a metal crystal, the multiple energy levels of all these orbitals are so densely packed that they are in effect a continuum, i.e. the electron no longer has to make quantised jumps between distinct energy states. If the energy continuum extends above the level of the highest energy electron, then if the electrons are given a tiny bit of extra kinetic energy (e.g. by a voltage gradient) they can move up slightly in energy - without making a quantised energy jump - and just move. Nothing stops them. This means they can flow freely through the solid without needing to overcome any energy "barrier" in order to free themselves from any particular "parent" atom. That's what happens in a conductor.

    You might like this link, which has pictures illustrating how this gives rise to a conduction band: Band theory of solids : Solid-state Device Theory
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    Wow. A chemist that has such knowledge of band structure? I am impressed exchemist. Most of chemist that I know just barely know what atomic orbital is.
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    Real Chemists study physics.
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    Quote Originally Posted by Gere View Post
    Wow. A chemist that has such knowledge of band structure? I am impressed exchemist. Most of chemist that I know just barely know what atomic orbital is.
    Phew, I thought you were about to tell me I had got it wrong!

    But seriously, I doubt what you say can really be true. Chemists use quite widely the idea of the atomic orbitals of a pair of atoms merging to form a pair of bonding and antibonding orbitals. It is the foundation of the theory of chemical bonding. It has always seemed to me the formation of "bands" is just the limiting case of an infinitely extended array of atoms. I do not pretend to know all the physics of it, though.
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    Quote Originally Posted by exchemist View Post
    Quote Originally Posted by fatman57 View Post
    Quote Originally Posted by Michael Anteski View Post
    Quote Originally Posted by Markus Hanke View Post
    Quote Originally Posted by Michael Anteski View Post
    I don't know if fatman 57 feels edified as to the standard quantum-theory explanation of "movement" of charge in an electric wire, but there is also an ether-theory model for this question he might want to listen to. -This model views the current as consisting of conduction of charge along the wire not by motion of discrete quantum "particles" (electrons), but as instantaneous resonation of elementary energic units. The mecanism of resonance is vibrational and it involves elementary ether-scale units. All the resonance occurs between these units which are much smaller in size scale than "electrons," which are really merely quantum-size "particle capacity" units formed via aggregational resonance of the elemental units. -A magnetic field represents a side-resonance effect in space to balance the "artificial" situation in which a wire is used to conduct the current. The magnetic field comprises mainly indentical elemental ether energic units which are also in resonance with the ether units inside the wire and traveling from one end (pole) to the other. -It can be appreciated that this is a simpler more rational and unifying model than the quantum mechanical model.
    MODERATOR WARNING : Michael Anteski, you have already been told previously to not post your fringe ideas into the main physics section, yet you persist in doing so. If you have a hypothesis to present, please do so in a separate thread in the appropriate section, i.e. New Ideas and Hypotheses. Consider this an official warning - next time I find your ether ideas in the main physics section, you will be send off on a holiday.
    As I have fully described my ether model in previous posts, I considered this last one an addendum. I don't plan any more posts here inasmuch as all I was really interested in was finding a sponsor with deep pockets to fund a field test I propose to prove an ether exists (I have also mentioned that test here before.) I believe there could be a fringe benefit if ether energy is produced. -I realize quantum theorists will probably only recognize a test demonstrating the ether exists.
    As far as I am aware the standard model is a preferred one to choose for many reasons. If this ether theory is not proved then maybe the moderators are correct in requesting it be discussed elsewhere. I am searching for a proven answer if possible. I like hearing about what else is going around though, so appreciate the input.


    @exchemist - thanks, a description about the valence shells is exactly what I am looking for. I would like to be able to visualize what is going on in there...

    @Harold - I can now sleep well thinking it is electron flow again, an electrician I spoke to talked more of the charges and said the electrons themselves didn't move, or at least not much. In an AC environment that would be understandable, but DC as far as I currently have it is a linear flow.
    OK. Let me try. When you have several atoms together, the individual atomic orbitals in the outermost ("valence") shells can merge to form new sets of multi-centre orbitals, with a wider range of energies than are present in isolated atoms. These will be filled up with electrons, starting from the lowest energy states, until all the electrons required for electrical neutrality are in. (This is something called the Aufbau Principle). The higher energy ones will remain empty unless an electron is excited (given more energy) enough to jump into one.

    In the case of individual molecules, these multi-centre orbitals are called "molecular orbitals" and are the theoretical basis of chemical covalent bonding. In the case of an extended (pseudo-infinite) array of atoms, such as you get in a metal crystal, the multiple energy levels of all these orbitals are so densely packed that they are in effect a continuum, i.e. the electron no longer has to make quantised jumps between distinct energy states. If the energy continuum extends above the level of the highest energy electron, then if the electrons are given a tiny bit of extra kinetic energy (e.g. by a voltage gradient) they can move up slightly in energy - without making a quantised energy jump - and just move. Nothing stops them. This means they can flow freely through the solid without needing to overcome any energy "barrier" in order to free themselves from any particular "parent" atom. That's what happens in a conductor.

    You might like this link, which has pictures illustrating how this gives rise to a conduction band: Band theory of solids : Solid-state Device Theory
    Thanks exchemsit - That really helped. The link explains it well too...!

    I presume in non-conductors the valence shells merge too? What makes them non-conductive?
    Last edited by fatman57; October 9th, 2013 at 10:17 AM.
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  33. #32  
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    Quote Originally Posted by fatman57 View Post
    Quote Originally Posted by exchemist View Post
    Quote Originally Posted by fatman57 View Post
    Quote Originally Posted by Michael Anteski View Post
    Quote Originally Posted by Markus Hanke View Post
    Quote Originally Posted by Michael Anteski View Post
    I don't know if fatman 57 feels edified as to the standard quantum-theory explanation of "movement" of charge in an electric wire, but there is also an ether-theory model for this question he might want to listen to. -This model views the current as consisting of conduction of charge along the wire not by motion of discrete quantum "particles" (electrons), but as instantaneous resonation of elementary energic units. The mecanism of resonance is vibrational and it involves elementary ether-scale units. All the resonance occurs between these units which are much smaller in size scale than "electrons," which are really merely quantum-size "particle capacity" units formed via aggregational resonance of the elemental units. -A magnetic field represents a side-resonance effect in space to balance the "artificial" situation in which a wire is used to conduct the current. The magnetic field comprises mainly indentical elemental ether energic units which are also in resonance with the ether units inside the wire and traveling from one end (pole) to the other. -It can be appreciated that this is a simpler more rational and unifying model than the quantum mechanical model.
    MODERATOR WARNING : Michael Anteski, you have already been told previously to not post your fringe ideas into the main physics section, yet you persist in doing so. If you have a hypothesis to present, please do so in a separate thread in the appropriate section, i.e. New Ideas and Hypotheses. Consider this an official warning - next time I find your ether ideas in the main physics section, you will be send off on a holiday.
    As I have fully described my ether model in previous posts, I considered this last one an addendum. I don't plan any more posts here inasmuch as all I was really interested in was finding a sponsor with deep pockets to fund a field test I propose to prove an ether exists (I have also mentioned that test here before.) I believe there could be a fringe benefit if ether energy is produced. -I realize quantum theorists will probably only recognize a test demonstrating the ether exists.
    As far as I am aware the standard model is a preferred one to choose for many reasons. If this ether theory is not proved then maybe the moderators are correct in requesting it be discussed elsewhere. I am searching for a proven answer if possible. I like hearing about what else is going around though, so appreciate the input.


    @exchemist - thanks, a description about the valence shells is exactly what I am looking for. I would like to be able to visualize what is going on in there...

    @Harold - I can now sleep well thinking it is electron flow again, an electrician I spoke to talked more of the charges and said the electrons themselves didn't move, or at least not much. In an AC environment that would be understandable, but DC as far as I currently have it is a linear flow.
    OK. Let me try. When you have several atoms together, the individual atomic orbitals in the outermost ("valence") shells can merge to form new sets of multi-centre orbitals, with a wider range of energies than are present in isolated atoms. These will be filled up with electrons, starting from the lowest energy states, until all the electrons required for electrical neutrality are in. (This is something called the Aufbau Principle). The higher energy ones will remain empty unless an electron is excited (given more energy) enough to jump into one.

    In the case of individual molecules, these multi-centre orbitals are called "molecular orbitals" and are the theoretical basis of chemical covalent bonding. In the case of an extended (pseudo-infinite) array of atoms, such as you get in a metal crystal, the multiple energy levels of all these orbitals are so densely packed that they are in effect a continuum, i.e. the electron no longer has to make quantised jumps between distinct energy states. If the energy continuum extends above the level of the highest energy electron, then if the electrons are given a tiny bit of extra kinetic energy (e.g. by a voltage gradient) they can move up slightly in energy - without making a quantised energy jump - and just move. Nothing stops them. This means they can flow freely through the solid without needing to overcome any energy "barrier" in order to free themselves from any particular "parent" atom. That's what happens in a conductor.

    You might like this link, which has pictures illustrating how this gives rise to a conduction band: Band theory of solids : Solid-state Device Theory
    Thanks exchemsit - That really helped. The link explains it well too...!

    I presume in non-conductors the valence shells merge too? What makes them non-conductive?
    Yes they do merge, but as I said in the earlier post, the resulting band gap is a big one. So you have a completely full band of merged "bonding" orbitals and another empty band (probably what a chemist might think of as an "antibonding" band), separated by an energy difference far too big to be bridged by applying an electric potential to the material. Since the valence band is full to the top, there is no slightly higher energy state available for an electron to occupy if it were given a bit of extra kinetic energy. In spatial terms this means they are frozen in their chemical bonds and cannot move through the solid, whereas in a conductor the presence of electrons in the conduction band, plus some empty "space" in the upper part of the continuum implies the electrons form a kind of delocalised "sea" in which the atomic "cores" (nuclei plus inner shells of electrons) are embedded.
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    Quote Originally Posted by Strange View Post
    Real Chemists study physics.
    And real physicists study maths.......at least they give the appearance of doing so, to chemists.......
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    I'm just bitter I didn't stick with chemistry like I should have!
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    Quote Originally Posted by Strange View Post
    I'm just bitter I didn't stick with chemistry like I should have!
    I nearly also added that real biologists study chemistry: would that have been too close to the bone, then?
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    I suppose it is time to post this again (I hope fatman57 doesn't mind us wandering off like this):

    xkcd: Purity
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    Quote Originally Posted by fatman57 View Post
    Thanks for the replies all!

    It does help, plus Harolds post for AC, but still doesn't tell me what a charge is.
    That's because we can't tell you what charge is in terms of anything more fundamental. We can say that charge is a property of electrons, but not uniquely. There are "fat" electrons (the muon is 207 times as massive, but has the same charge as an electron), for example. There are also some flavors of quarks which have charge measured in fractions of an electron's charge. That still doesn't tell us what charge "is," I'm sorry to say.

    If it is like a tube of marbles and since I use electrons to push through (DC) then the pipe will always be full or marbles no matter what.
    That's exactly right, and exactly analogous to the constant availability of mobile electrons in a wire, e.g.. The wire remains electrically neutral overall. As many electrons exit as enter during conduction, just as marbles can enter and exit the tube without changing the number of marbles in the tube.

    But my question is more because as far as I know electrons are negatively charged and protons positively charged - how does the charge actually get transferred though the wire?
    I think you've gotten the answer to that question, but just in case not, strange made an important statement: A conductor (**of the type modeled with the marbles-in-tube picture) is a conductor precisely because there is a mobile charge carrier (e.g., the electron). Electrons come in one end, and exit the other because they are mobile. The nuclei -- and most of the other electrons bound to them -- are not. Only the outermost electrons are mobile (as wonderfully explained by exchemist).

    I like a particle theory to explain things (even though not everything can be explained in this way), the mechanics of charge being transferred in this case eludes me...unless it is simply a wave (it was explained to me that waves in the ocean do not involve the forward movement of water atoms which stay still, simply move up and down and that is the wave?).
    Hopefully the mobile-electrons-as-marbles picture makes more sense now. It is a perfectly serviceable model for basic conduction in a wire, and is one that satisfies your desire for a particle-based explanation. If you then want to ask why wires are wires, and semiconductors and insulators aren't, then we'll have to add a few more layers of explanation (and ones that will not gracefully allow a pure particle picture, unfortunately).

    **ETA: parenthetical clause added above; marked with asterisks. Some bits deleted in that sentence.
    Last edited by tk421; October 9th, 2013 at 07:42 PM.
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    Quote Originally Posted by tk421 View Post
    A conductor is a conductor precisely because one charge carrier (e.g., the electron) is mobile, while the other is not.
    That is an interesting point that I hadn't thought about explicitly. It is certainly true in metals (and semiconductors). But what about, for example, a solution of a salt where there are equal numbers of positive and negative ions as charge carriers (or a plasma). This conducts, even though both charge carriers are mobile. Does it behave identically to a metal conductor? I assume you could build a solenoid with a coiled tube containing an electrolyte solution, for example.
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    Quote Originally Posted by Strange View Post
    Quote Originally Posted by tk421 View Post
    A conductor is a conductor precisely because one charge carrier (e.g., the electron) is mobile, while the other is not.
    That is an interesting point that I hadn't thought about explicitly. It is certainly true in metals (and semiconductors). But what about, for example, a solution of a salt where there are equal numbers of positive and negative ions as charge carriers (or a plasma). This conducts, even though both charge carriers are mobile. Does it behave identically to a metal conductor? I assume you could build a solenoid with a coiled tube containing an electrolyte solution, for example.
    Thanks for reading carefully, as always, Strange. I need to reword my explanation (I was continuing to stick with the marbles-in-tube model in my head, but the quote above fails spectacularly to make that clear). I will post an amendment shortly. An ionic solution will conduct just fine, with the possible complication of redox reactions changing the availability of charged entitites at different potentials.
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    Quote Originally Posted by MacGyver1968 View Post
    No, she's just much too over-demonstrative and just possibly much too oversexed.
    teaching a class of twenty two assorted engineers about vibration
    Ahh...the jokes just write themselves!
    You are very clever *L*....well done.
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    Quote Originally Posted by Strange View Post
    I suppose it is time to post this again (I hope fatman57 doesn't mind us wandering off like this):

    xkcd: Purity
    Well I at least had not seen this before so thanks.

    By the way, I've never known with you whether your picture of Romanesco Broccoli indicates a biological bent or a mathematical one - or indeed somewhere on the intervening spectrum. They make wonderful fractal sculptures - it would an interesting curiosity to know the algorithm that generates it. Unfortunately to my mind the taste is disappointing. But I digress.
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    Quote Originally Posted by exchemist View Post
    By the way, I've never known with you whether your picture of Romanesco Broccoli indicates a biological bent or a mathematical one
    There is no particular significance. It is just an amazing thing (I'm surprised creationists haven't jumped on it - it just looks so "designed").

    I suppose, if anything, it could symbolizes a crossover between the visual arts, math, science, and food.
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    As good as exchemist's explanation is, I think he left out one key aspect. A conductor conducts because the conduction bands are not completely filled with electrons. However, in the case of a pure (undoped) semiconductor, the bands ought to be either be either completely filled or completely empty, and hence no conduction. But the lowest empty band is close enough to the highest filled band that electrons can be thermally promoted (consider the Boltzmann distribution) to the lowest empty band, and thus the bands are no longer completely filled. Note that the conductivity of a semiconductor increases with temperature (unlike a metal). In the case of an insulator, the lowest unfilled band is so far above the highest filled band that the thermal equilibrium population of electrons in the lowest unfilled band is negligible.
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    Quote Originally Posted by Strange View Post
    Quote Originally Posted by exchemist View Post
    By the way, I've never known with you whether your picture of Romanesco Broccoli indicates a biological bent or a mathematical one
    There is no particular significance. It is just an amazing thing (I'm surprised creationists haven't jumped on it - it just looks so "designed").

    I suppose, if anything, it could symbolizes a crossover between the visual arts, math, science, and food.
    Strange, I am disappointed in you. Discerning people are well aware that broccoli is not food, but an instrument of torture for sadistic parents.
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    Quote Originally Posted by John Galt View Post
    Strange, I am disappointed in you. Discerning people are well aware that broccoli is not food, but an instrument of torture for sadistic parents.
    Another one for the ignore list!
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    Quote Originally Posted by John Galt View Post
    Quote Originally Posted by Strange View Post
    Quote Originally Posted by exchemist View Post
    By the way, I've never known with you whether your picture of Romanesco Broccoli indicates a biological bent or a mathematical one
    There is no particular significance. It is just an amazing thing (I'm surprised creationists haven't jumped on it - it just looks so "designed").

    I suppose, if anything, it could symbolizes a crossover between the visual arts, math, science, and food.
    Strange, I am disappointed in you. Discerning people are well aware that broccoli is not food, but an instrument of torture for sadistic parents.
    YOU DO have a sense of humor!! MIRACLE!!!...oops those aren't scientific!!!
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    Thanks for all the replies - the banter is welcome!

    Quite a bit to take in but I had a quick read and I would say I am happy with the explanations by tk421 and exchemist - thank you so much for your help!!!
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    Quote Originally Posted by KJW View Post
    As good as exchemist's explanation is, I think he left out one key aspect. A conductor conducts because the conduction bands are not completely filled with electrons. However, in the case of a pure (undoped) semiconductor, the bands ought to be either be either completely filled or completely empty, and hence no conduction. But the lowest empty band is close enough to the highest filled band that electrons can be thermally promoted (consider the Boltzmann distribution) to the lowest empty band, and thus the bands are no longer completely filled. Note that the conductivity of a semiconductor increases with temperature (unlike a metal). In the case of an insulator, the lowest unfilled band is so far above the highest filled band that the thermal equilibrium population of electrons in the lowest unfilled band is negligible.
    Thanks for the extra clarification.
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    Quote Originally Posted by John Galt View Post
    Quote Originally Posted by Strange View Post
    Quote Originally Posted by exchemist View Post
    By the way, I've never known with you whether your picture of Romanesco Broccoli indicates a biological bent or a mathematical one
    There is no particular significance. It is just an amazing thing (I'm surprised creationists haven't jumped on it - it just looks so "designed").

    I suppose, if anything, it could symbolizes a crossover between the visual arts, math, science, and food.
    Strange, I am disappointed in you. Discerning people are well aware that broccoli is not food, but an instrument of torture for sadistic parents.

    ....except for purple sprouting broccoli, which makes a mean combination with anchovies, garlic and chilli to go with pasta, and the tenderstem variety, which is good in stir-fries. My 10yr old son loves it.
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    The way I was taught in school anout ecletric charge was when you rip up small pieces of paper and comb your hair with a plactic comb,when you put the comb near the papers,that was electric charge and it was measured in columbs.In the crystal structure of a conductive metal the atoms are in a fixed position.The valence electrons are free to move.So the valence electrons move across the atoms in the conductor.Push on one side and it comes out the other so to speak.
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