Conductors in large electric fields

[gralla55]

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?

 

[Drakkith]

Offhand I'd say you would ionize the conductor and rip it apart.

 

[ModusPwnd]

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.

 

[marcusl]

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).

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.

 

[sardar]

I can assure you that there is indeed a limit to how big an opposing field the charges in a conductor can create. This limit is known as the breakdown voltage or dielectric strength of the material. Once the electric field inside the conductor reaches this limit, the charges in the conductor will no longer be able to create an opposing field and the conductor will experience a breakdown. This can result in the formation of an electrical arc or spark, which can potentially damage the conductor.

In addition, the behavior of a conductor in a large electric field also depends on the material and shape of the conductor. For example, a pointed conductor will have a lower breakdown voltage compared to a smooth, rounded conductor. This is because the electric field is concentrated at the pointed tip, leading to a higher charge density and a breakdown at a lower field strength.

Furthermore, the surrounding environment and atmospheric conditions can also affect the behavior of a conductor in a large electric field. For instance, high humidity can decrease the breakdown voltage of a conductor due to the presence of moisture and ions in the air.

In summary, it is important to consider the material, shape, and environmental factors when placing a conductor in a large electric field. Going beyond the maximum opposing field of a conductor can result in a breakdown, potentially causing damage to the conductor and surrounding equipment. Therefore, it is crucial to carefully design and select appropriate conductors for use in high electric fields.