####
2.1.1 Superposition Principle

The field of a single charge can be obtained from the
expression
above. This field is shown in the following simulation by using a
vector
(force on a unit (invisible) charge) at different points in space.

The *Superposition Principle* allows us to
generalize
the previous result to systems with more than one charge: *the total
field is the vector sum of the individual field due to each charge
separately*.
This Principle is a consequence of the linearity property of the field
equations.

Let us see next the field produced at point
(300,0,500)
by two charges. We show the field due to a negative charge (-5000 u)
placed
at (770,0,0), the field of a positive charge (+10000 u) placed at
(0,0,0),
and the field due to both charges simultaneously.

Load
experiment 2

Load
experiment 3

Load
experiment 4

The superposition of the two fields yielding the
total
field is shown in next Figure.

Let us remark once more the importance of this
Principle
to generalize the concepts defined for a charge to systems with an
arbitrary
number of charges.