Limit on Faraday's cage (rearranging charges)

AI Thread Summary
Applying a magnetic field to a Faraday cage causes charges within the conductive material to rearrange, creating an opposing field that ideally results in a net field of zero inside the cage. However, the discussion raises the question of whether a sufficiently strong external field could exceed the finite amount of charges available for rearrangement, potentially leading to a non-zero net field inside the cage. The need for specific numerical values regarding field strengths and charge quantities is emphasized to clarify the scenario. This inquiry touches on the limits of Faraday cage effectiveness under extreme conditions. Ultimately, understanding these dynamics is crucial for assessing safety in high-field environments.
olu
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Having a question regarding Faraday's cage,Applying a magnetic field over the cage, will cause the charges in the conducting cage to rearrange, thus causing another field which opposes the first field. This will give a net field inside the cage of zero (this is why we are safe in a car during a lightning).

http://en.wikipedia.org/wiki/Faraday_cage#/media/File:Faraday_cage.gif

However, since we have a finite amount of charges in the conductive cage. Is it possible to apply a field strong enough so that all the charges have rearranged to oppose the field, but with the fact that all the charges is not enough charges to cancel the field, and thus giving a net field inside the cage which is not zero?
Oscar
 
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olu said:
we have a finite amount of charges in the conductive cage.

Could you put a number on that? It could help you to get a handle on what you are saying. What field strengths are you considering? If this isn't a fruitless 'irresistible force and immovable object' type question then you need to supply some orders of magnitude for the causes and effects that you are discussing.
 
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