On a separate piece of paper sketch the equipotential lines and the electric field lines for the following charge distribution. Both elements are charged conductors. Object: To determine the nature of equipotential lines and electric field lines for several electrode configurations, and to determine the behavior of a insulator and conductor in the presence of an electric field. Theory: Since the electric potential is the result of integrating the electric field along a displacement, the inverse operation would be that the rate that the electric potential changes with position would yield the electric field strength in. We may regard the equipotential lines to be similar to the lines of constant elevation on a topographical map. The electric field lines then must be indicated by the rate and direction that the 'elevation' changes. The closer the equipotential lines are the steeper the slope or the faster the rate of change; i.e., the larger the electric field. In addition, we find that the electric field must be perpendicular to the equipotential lines, thus we have the following rules for electric field lines, electric fields and equipotentials. General Rules for Electric Field Lines and Equipotentials: 1. The electric field (vector) is tangent to the electric field line. 2. Electric field lines start on positive charges and point toward negative charges. Electric field lines terminate on negative charges. 3. Electric field lines are perpendicular to equipotential surface. 4. The number of electric field lines in an area is proportional to the magnitude of the electric field in that region. 5. Electric filed lines never cross. 6. The closer equipotential surfaces are to each other, the stronger the electric field is in that region.