Question

Conceptual Question
A uniform electric field exists in a region of space containing no charges. What can you conclude about the
net electric flux through a gaussian surface placed in this region of space?

Answer 1

The net flux through any gaussian surface is zero. We can argue it two ways. Any surface contains zero charge, so Gauss's law says the total flux is zero. The field is uniform, so the field lines entering one side of the closed surface come out the other side and the net flux is zero.