1) 10 Coulombs of charge are placed on a spherical conducting shell. A particle with a -3C point charge is placed at the center of the cavity. The net charge in coulombs on the inner surface of the shell is what?
2) A 30 N/C uniform electric field points perpendicularly towards the left face of a large neutral conducting sheet. The area charge density on the left and right faces, respectively are what?
3) Charge Q is distributed uniformly throughout an insulating sphere of radius R. The magnitude of the electric filed at point R/2 from the center is what?