Electrodynamics
Right-handed coordinate systems
In order to investigate the electromagnetic field structure it is appropriate to be
acquainted with the basic mathematical definitions and physical postulates in
classical electrodynamics. First it is worth pointing out that a quantity is either a
vector or a scalar. Scalars are quantities, which are fully described by a
magnitude alone. Vectors are quantities, which are fully described by both a
magnitude and a direction. Because we will work mostly with vectors we have to
define what is positive normal to given surface s, what is positive direction of
given contour Γ and what is right-handed coordinate system?
Right-handed coordinate system Oxyz is such system in which if the z-axis points
towards your face the counterclockwise rotation of the Ox axis to the Oy axis has
the shortest possible path. The positive normal +n of given surface s closed by
contour Γ is collinear with the Oz axis of right-handed coordinate system Oxyz
whose x- and y-axis lie in the plane of the surface. The positive direction of the
contour Γ is the direction in which the rotation of x-axis to the y-axis has the
shortest possible path.
Fig. 3 Direction ofthe positive normal and right handed coordinate system.
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