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1.3.3 Charge and Equipotential Surface

A different form of visualizing the effect of a charge
on
the surrounding space is in terms of equipotential surfaces.

Set
desiredPotentialValue = 400.0

Set
potentialSurfaceGrid = 50

For an isolated charge, the equipotential surfaces are
spheres centred at the charge. A general result is that field lines are
orthogonal to equipotencial surfaces.

Rotate the cube to get a 3-D view of the system
charge
+ equipotential surfaces.

The introduction of the electric potential, that can
be
easily justified in Electrostatics since the static **E** field is
conservative,
allows a description of electrostatic phenomena in terms of a scalar
field.
This description is mathematically simpler and, at the same time
equivalent
to the description in terms of the *vector electric* field (which
has been used in the previous simulation through visualization of the
force
lines).

In both cases, space is "labelled" at each point
with
the value of a vector or a scalar, respectively.