This diagram shows the electric field lines for a dipole.
The dashed lines show lines of equal potential for this system.
Notice that the equipotential lines are always perpendicular to the E field lines.
Recall the relationship between the electric field and the electric potential.
The change in potential is the negative integral of the electric field over a distance.
The electric field is the negative gradient of the potential.
In a one-dimensional case, the negative slope of the potential gives us the E field, as we can see in this
graphical representation. Similarly, if we know the electric field as a function of x, we can find
the potential by finding the negative area under the curve of the E field.
We can also analyze an electric field by plotting equipotential curves on a grid. Here, the grid squares are 1 cm x 1 cm.
The blue dashed lines are equipotential curves.
Estimate the E field strength and direction at points A, B and C.