E1: Start with the default setting (single source, z = 0.1).

Control if the distribution is of rotational symmetry. You will notice deviations for very small values of the coordinates; these are numerical artifacts that you should disregard.

E 2:  What do you see? (the position of equipotential lines of equal potential distance in a plane close to the source).

E 3:  Choose a greater distance z by means of the slider. What do you see? (the xy- potential distribution in a plane parallel to the z = 0 plane. The lines, except for the central one, are not identical to lines in plots with other distance z. For every plot 35 lines are calculated within the coordinate range.

E 4:  Try to develop a 3 dimensional conception of the potential function. It should be of rotational symmetry around any straight line through the origin ~ point symmetry.

E 5:  Choose the 2 body case. Repeat the experiments described above.

Now the distribution is no longer of rotational symmetry. When you shift z, you will see ranges where equipotential lines enclose both sources; this is the near field. Then you can see ranges where they disaggregate into two separate equipotential lines; this is the far field. In between there exists a neutral point.

E 6:  Change the distance between the objects with slider R. Playing around with R, z and V you can study situations for a great range of parameters.

E 7: With slider b<1 change the relation of the size of both objects. b defines the relation of the second object to the first one. This simulates for example a star with a smaller companion.

E 8:  Repeat the experiments for the case of 3 bodies. Now sliders b and c are active to define the relative sizes. This may simulate a sun, earth and moon situation (not with respect to the real distances!)

E 9: Choose the dipole and reflect what determines the difference to the 2 body case. Is there an axis of symmetry which leads to the 3D configuration of the equipotential lines? Observe how fast the potential declines with distance, compared to the 2 body situation.

E 10:  Study the quadrupole. Here the fast decline with distance is still more striking. Why?

E 11:  Edit the formulas and speculate in advance what you should see and why!