Timeline for Non-conservative electric fields due to changing magnetic flux?
Current License: CC BY-SA 3.0
10 events
| when toggle format | what | by | license | comment | |
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| Oct 25, 2013 at 1:55 | vote | accept | stochastic13 | ||
| Oct 21, 2013 at 12:51 | comment | added | Nicolas | @SatwikPasani True, but the fact that the field accelerates charges does NOT mean the field is not conservative (counter examples : any conservative force). The difference here is that the electric field comes from induction (motion in magnetic field). In other words : the electric field created by static charges IS conservative; the electric field that you see as a result of moving in a magnetic field is NOT conservative. | |
| Oct 17, 2013 at 13:30 | comment | added | stochastic13 | @Nicolas but then this acceleration which averages to a constant drift velocity is also present in normal cases where the field is conservative, as in a current in a simple DC circuit. Why then here the field is non-conservative? | |
| Oct 1, 2013 at 11:51 | history | edited | Nicolas | CC BY-SA 3.0 |
clarifications concerning conservative/non-conservative.
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| Oct 1, 2013 at 11:47 | comment | added | Nicolas | @SatwikPasani More precisely, all charges get permanently accelerated, but collisions within the conductive material slow them down (and heat said material) so in average their velocity is constant. That's quite similar to the fall of a body in a fluid, where collisions with air molecules (called viscosity at a large scale) compensate a constant gravity force, leading to a constant fall velocity. I edited the answer with respect to the conservative/non conservative nature of the electric field. | |
| Oct 1, 2013 at 11:40 | comment | added | Nicolas | @BMS : In this case, it actually is an example of the Ohm's law, stated as the current is proportionnal to the voltage between two points. You just have to extend the "voltage difference" definition to be the integral of electric field along the wire. Of course there is obviously no correct definition of voltage here as the electric field is inductive, therefore is not the gradient of a scalar field ; however this is the case for most generators. Indeed the basic mechanism (electric field acceleration compensating collisions) is at work here. | |
| Sep 30, 2013 at 16:24 | comment | added | stochastic13 | So once the constant current is established, accelerations cease to exist in the stationary frame? how can we then justify non-conservative field by charges obeying a law which predicts a conservative field under non-accelerated conditions? | |
| Sep 30, 2013 at 15:56 | comment | added | BMS | A constant current in this case is not an example of Ohm's law. | |
| Sep 30, 2013 at 14:36 | history | edited | Nicolas | CC BY-SA 3.0 |
added 205 characters in body
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| Sep 30, 2013 at 14:30 | history | answered | Nicolas | CC BY-SA 3.0 |