Induced Electric Field inside Faraday Cage

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Discussion Overview

The discussion revolves around the behavior of electric fields within a Faraday cage, specifically in the context of a hollow toroidal conducting chamber and a solenoid placed inside it. Participants explore the implications of electromagnetic induction and the shielding properties of the Faraday cage.

Discussion Character

  • Debate/contested
  • Conceptual clarification
  • Technical explanation

Main Points Raised

  • One participant posits that a changing magnetic flux from a powered solenoid will induce an electric field within the toroidal chamber, regardless of the Faraday cage's presence.
  • Another participant argues that a Faraday cage does not suppress electromagnetic fields inside it but rather shields against external fields, suggesting that experiments inside should proceed normally.
  • There is a clarification sought regarding the position of the solenoid, with a participant reiterating the question about its placement outside the chamber.
  • Some participants express differing interpretations of the initial question, indicating a potential misunderstanding regarding where the electric field is generated.
  • A participant emphasizes that if an internal field exists, it remains contained, drawing an analogy to a microwave oven, while external fields are prevented from entering.

Areas of Agreement / Disagreement

Participants exhibit disagreement regarding the implications of the Faraday cage on induced electric fields, with multiple competing views on how electromagnetic fields behave in this scenario. The discussion remains unresolved.

Contextual Notes

There are unresolved assumptions regarding the nature of the electric field's propagation and the specific conditions under which the Faraday cage operates. The discussion also touches on boundary conditions relevant to Maxwell's equations.

TESL@
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Imagine there is a hollow toroidal conducting chamber and a long solenoid in the middle. When we power the coil, does the induced electric field "propagate" inside the chamber? My prediction is that the changing flux will cause induction regardless of the cage.

Thank you.
 
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A Faraday cage does not suppress electromagnetic fields inside it - it just shields from external fields.
Therefore any electricity/electromagnetism experiment inside a Faraday cage should proceed normally... the chamber walls you describe would be the boundary conditions for the Maxwel equations ... look up "wave guide".
 
I am asking what if the solenoid is outside the chamber, in the middle of the toroid.
 
TESL@ said:
I am asking what if the solenoid is outside the chamber, in the middle of the toroid.

Then reread Simon's first sentence :)
 
His first sentence sounds to me like he has understood the question differently, as if the field is generated inside the chamber.
 
TESL@ said:
His first sentence sounds to me like he has understood the question differently, as if the field is generated inside the chamber.

Simon Bridge said:
A Faraday cage does not suppress electromagnetic fields inside it - it just shields from external fields.

Note the bolded section of what Simon said ... that is your answer

if there is an internal field, it won't get out ... aka a microwave oven
if there is an external field it won't get in eg ...

Tesla18Dalek.jpg
cheers
Dave
 
Last edited:
Thank you both.
 
No worries :)
 

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