Key Terms

area vector

vector with magnitude equal to the area of a surface and direction perpendicular to the surface

cylindrical symmetry

system only varies with distance from the axis, not direction

electric flux

dot product of the electric field and the area through which it is passing

flux

quantity of something passing through a given area

free electrons

also called conduction electrons, these are the electrons in a conductor that are not bound to any particular atom, and hence are free to move around

Gaussian surface

any enclosed (usually imaginary) surface

planar symmetry

system only varies with distance from a plane

spherical symmetry

system only varies with the distance from the origin, not in direction