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etotheipi

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They say that electrons inside the walls of the Faraday cage move freely until they reach equilibrium. We end up with a small net negative charge on the lower side of the Faraday cage and a net positive charge on the upper side, which sets up an electric field

*inside the walls*, pointing downward, of magnitude ##\frac{m_eg}{e}##. They then say that this same homogenous electric field must also exist inside the Faraday cage (otherwise we would have a non-zero line integral of ##\vec{E}## along a path through the wall and the interior), and as a result the electric force on the internal electron exactly balances the gravitational force... so the electron floats (i.e. the Faraday cage effectively "shields the gravitational field").

My problem with that explanation is that if the walls of the Faraday cage are conducting, there should be no electric field inside them (see red part). I wondered if someone could clarify what's going on? Thanks