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Figure 3: A spherical electric field. If the positive z-axis is given a uniform positive charge density, and the negative z-axis is given an equal and opposite charge density, the resulting field lines are spherical, that is, in the theta_hat direction.
Figure 5: An ellipsoidal electric field. If the oppositely charged half-lines in the spherical example are separated by a finite gap, the resulting field lines are ellipsoidal.
