ELECTRIC field due to a solenoid, or a current-carrying wire, or

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The discussion focuses on the electric fields produced by current-carrying conductors like solenoids and wires, questioning why they are often overlooked. It highlights that while a changing magnetic field generates an electric field, steady currents do not produce electric fields due to the principles outlined in Maxwell's equations. Specifically, the absence of changing magnetic fields results in no curl, and the neutrality of the current-carrying wire leads to no divergence. However, within a conductive wire, Ohm's law indicates that an electric field exists, although it may be constant and have zero divergence. The conversation concludes that the curl of the electric field remains zero due to the constant charge density.
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We always talk about the magnetic field produced by solenoids, straight wires of current, and rings of current, etc., but why do we never talk about the ELECTRIC fields produced by these geometries? I mean, there are CHARGES, right? So there must be electric fields present, right? Or am I wrong?

I know a CHANGING magnetic field produces an electric field, but why don't STEADY currents produce electric fields?
 
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This just follows directly from Maxwell's equations. With no changing B field the E field has no curl (Faraday's law), and with no net charge the E field has no divergence (Gauss' law). A field with no curl and no divergence is identically 0.
 
Current-carrying wires contain equal amounts of positive and negative charge, and are electrically neutral.
 
DaleSpam said:
. A field with no curl and no divergence is identically 0.

well, it may be constant in general. in case of wire with conductivity sigma, there is electric field inside the wire( given by ohm's law).. although if the current is steady and the conductivity uniform the divergence of the electric field becomes ZERO.
is the curl of electric field in this case also zero? i guess it should be because charge density in this case is constant with time everywhere.
 
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