Conductors in large electric fields

AI Thread Summary
When a conductor is placed in a strong electric field, its internal charges rearrange to create an opposing field, nullifying the field within the conductor. However, there is a limit to how strong this opposing field can be. If the external electric field exceeds this limit, the conductor may lose its conductive properties, potentially becoming an insulator. This can lead to phenomena such as field emission, where electrons are ejected from the surface, and possibly result in arcing. Ultimately, while the bulk of the material remains conductive, its behavior under extreme fields can change significantly.
gralla55
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You place a conductor in an electric field. The charges inside the conductor will relocate, to form an opposing electric field which cancels the outside field, making the field inside the conductor zero.

However, surely there's a limit to how big an opposing field the charges in the conductor can create. My question is, what will happen if you place a conductor in an electric field larger than the conductors maximum opposing inside field?
 
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Offhand I'd say you would ionize the conductor and rip it apart.
 
gralla55 said:
My question is, what will happen if you place a conductor in an electric field larger than the conductors maximum opposing inside field?

I would guess it not longer behaves as a conductor. Being a conductor means you have free and mobile charges. If your external field has pinned down all your charges then you now have an insulator.
 
Drakkith said:
Offhand I'd say you would ionize the conductor and rip it apart.
Right, you get field emission, which is the emission of electrons from the conducting surface. Eventually you could get an arc (lightning bolt).

ModusPwnd said:
I would guess it not longer behaves as a conductor. Being a conductor means you have free and mobile charges. If your external field has pinned down all your charges then you now have an insulator.
No, the bulk metal is still a conductor.
 
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