Hi, I hope this is advanced enough to warrant being in this section: I'm supposed to use the Gauss theorem (and presumably his law) to show: 1)The charge on a conductor is on the surface. 2)A closed hollow conductor shields its interior from fields due to charges outside, but doesn't shield its outside from fields due to charges placed inside it. 3)The field at the surface is normal to the surface and of magnitude (charge density)/epsilon0 I'm aware of the qualitative justifications but can't see how to do it this way. Can someone bail me out? Thanks.