Force between walls of faraday cage and charge inside

[goran d]

Is there a force in this case: For the sake of simplicity, a spherical Faraday cage. A smaller charged sphere inside. If we move the small sphere close to the wall of the cage, will there be a force of attraction between the wall of the cage and the small charged sphere?

 

[Meir Achuz]

Yes. You can find the force by using an image charge.