1. The problem statement, all variables and given/known data a) In a certain region of space, the volume charge density p has a uniform positive value. Can E be uniform in this region? Explain. b) Suppose that in this region of uniform positive p there is a "bubble" within which p=0. Can E be uniform within this bubble? Explain. 2. Relevant equations E = electric field Gauss's law: Flux= ∫ E dA = Q/ε0 3. The attempt at a solution I thought that if the volume charge density p were uniform, E would also be uniform because the charge enclosed by a Gaussian surface would be the same everywhere. However my book says that in a region where "the electric field E is uniform... the volume charge density p must be 0."