Continuous Faraday cage

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skin depth vs. frequency materials @ room temperature, red vertical line denotes 50 hz frequency:




effectiveness of shielding of static electric field largely independent of geometry of conductive material, however, static magnetic fields can penetrate shield completely.


in case of varying electromagnetic fields, faster variations (i.e., higher frequencies), better material resists magnetic field penetration. in case shielding depends on electrical conductivity, magnetic properties of conductive materials used in cages, thicknesses.


a idea of effectiveness of faraday shield can obtained considerations of skin depth. skin depth, current flowing in surface, , decays exponentially depth through material. because faraday shield has finite thickness, determines how shield works; thicker shield can attenuate electromagnetic fields better, , lower frequency.








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