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For example a d.c. electric current carrying naked wire inserted inside the electrostatic field between the two plates of a vacuum capacitor and with the wire not touching the two plates of the capacitor. Let's assume a straight segment of the wire is parallel to the electrostatic field of the capacitor but the electric field of the current inside the wire which we know by theory in this case is Ew≠0 is antiparallel to the electrostatic field of the fully charged capacitor Ec. (i.e. we assume the capacitor is ideal and has no dielectric leakage due a perfect vacuum).

We assume the steady voltage source powering the wire is positioned outside the electrostatic field of the capacitor Ec, far away.

For Ecw (induced Ec field inside wire) =-Ew by superposition will the electric current inside this wire segment nullified and therefore no current is flowing through the wire connected to the voltage source? The capacitor is fully charged by a second different steady voltage source.

There are contradicting theoretical answers in two different pse questions asking actually the same core question:

Effect of an external electric field on a electric current

If a current flows through a wire connecting two poles of a battery, how high an external voltage must I apply to stop the current flowing?

My interest is if this is actually experimentally resolved?

Note: As far as I know a d.c. electric current carrying wire is electrostatic neutral on its surface there is no charge build up on its surface and there is no any opposing surface field (i.e. no electrostatic equilibrium) that could prevent penetration of the Ec capacitor field inside the wire and therefore influencing its current due superposition with the existing Ew second electric field.

Markoul11
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  • Does this answer your question? [If a current flows through a wire connecting two poles of a battery, how high an external voltage must I apply to stop the current flowing?] (https://physics.stackexchange.com/questions/635907/if-a-current-flows-through-a-wire-connecting-two-poles-of-a-battery-how-high-an). If not, please cite this question and explain in detail the difference between your question here and that one – Dale Jun 11 '21 at 11:24
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    Flash memory is based on this principle. – my2cts Jun 11 '21 at 12:14
  • @my2cts I guess you mean more specifically cmos flash memory. – Markoul11 Jun 11 '21 at 12:20
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    Excellent, I like the appeal to experiment. That is a good question and distinct from the others. – Dale Jun 11 '21 at 12:29
  • @my2cts except that flash memory relies on non-linear components. This specific question has no non-linear components. – Dale Jun 11 '21 at 12:32
  • @markoul11 said “ As far as I know a d.c. electric current carrying wire is electrostatic neutral on its surface there is no charge build up on its surface” I gave you three or four peer reviewed papers that explain that this is false. Did you not read them? – Dale Jun 11 '21 at 17:01
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    See: (most authoritative) doi.org/10.1119/1.18112 (my personal favorite) doi.org/10.1119/1.5095939 (other similar references) doi.org/10.1119/1.5095939 doi.org/10.1119/1.3456567 (video demonstration of surface charge on DC circuit) youtu.be/U7RLg-691eQ There are many more similar references. The fact that there is a surface charge distribution on DC current carrying wires is very well known. Please read these papers this time – Dale Jun 11 '21 at 18:27
  • @Dale I am not convinced from the video presentation. I believe it is misleading. I would prefer if he had used a naked uniform wire and connected a large single current limiting resistor close to one of the terminals of the power supply. This could be explained easily by the ionization of the dielectric coating on the resistors and not due any electrostatic charge on the naked wire. A current carrying metal wire cannot have any static charge since all of its free charges are in motion and the atoms are neutral unless some of the its atoms are ionized which is very difficult in 99.99% copper. – Markoul11 Jun 11 '21 at 19:15
  • Found this analysis interesting https://iopscience.iop.org/article/10.1088/0143-0807/33/3/513 although for practical applications overcomplicated. I am afraid this cannot be resolved by classical analysis since it is a hybrid problem involving also condensed matted physics. An experiment would be great! I can't find unfortunately any such practical experiment and it must be performed in a vacuum. Currently there are commercial vacuum capacitors at 25KV and higher rating. https://en.wikipedia.org/wiki/Vacuum_variable_capacitor – Markoul11 Jun 11 '21 at 19:47
  • @Markoul11 said “I am not convinced from the video presentation”. And what about the four peer reviewed papers (one of them by Jackson)? Did you also decide that Jackson is not convincing? – Dale Jun 11 '21 at 20:55
  • @Markoul11 said “I believe it is misleading. I would prefer if he had used a naked uniform wire and connected a large single current limiting resistor close to one of the terminals of the power supply.” This is only because you do not understand how the surface charges are predicted to behave. His setup is perfectly legitimate and his results consistent with the standard theory on the topic. If you read the actual peer reviewed literature you will see that the experiment was legitimate and your dismissal of it is based on ignorance. The video is a supplement to the papers, not a substitute – Dale Jun 11 '21 at 21:09
  • Note that the video is not experimental evidence regarding your main question, but it is clear experimental evidence refuting your final paragraph. Early electroscopes also used mechanical effects on pieces of foil to measure charge. So this is a crude but standard measurement of charge. The result is unambiguous. There is clearly measurable charge on the conductive wire carrying a DC current. – Dale Jun 12 '21 at 02:22

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Not at all in classical physics, assuming the wire is made of a simple conducting medium.

Very little if correction to solid state physics is taken into account: The charge density within a (nanometers) thin layer near the conductor surface will change due to bound charges. They can influence conductivity especially for high-frequency currents.

Still the effect will likely be negligible in bulk metal, but it could be measurable if the wire was made of semiconductor or (evaporated) metal film of sub-nanometric thickness.

dominecf
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