The document discusses three common orthogonal coordinate systems used in electromagnetics: 1) Cartesian (or rectangular) coordinate system which locates a point as the intersection of three perpendicular planes. 2) Cylindrical coordinate system which uses a radial distance, azimuth angle, and longitudinal coordinate. 3) Spherical coordinate system which orients a point using radial distance, polar angle, and azimuth angle.

1. EC8451- ELECTROMAGNETIC FIELDS
Dr.K.G.SHANTHI
Professor/ECE
shanthiece@rmkcet.ac.in
ORTHOGONAL COORDINATE SYSTEMS

2. ORTHOGONAL COORDINATE SYSTEMS
 The physical quantities that are being dealt in Electromagnetics are
functions of space and time.
 In a three-dimensiona1 space, a point can be located as the intersection
of three surfaces.
 When these three surfaces are mutually perpendicular to one another,
then it is known as an orthogonal coordinate system.
 An orthogonal system is one in which the coordinates are mutually
perpendicular.
 The three orthogonal coordinate systems that are most common and
useful are:
1. Cartesian (or rectangular) coordinate system
2. Cylindrical coordinate system
3. Spherical coordinate system
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3. The unit vectors of the rectangular
coordinate system have unit
magnitude and are directed
toward increasing values of their
respective variables.
A point P in Cartesian coordinates is the
intersection of three planes
Cartesian (or Rectangular) Coordinate System (x,y,z)

4. Cartesian (or Rectangular) Coordinate System (x,y,z)
✘ A point P(x1, y1, z1) in Cartesian coordinates is the intersection
of three planes specified by x = x1, y = y1 and z = z1
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5. Cartesian (or Rectangular) Coordinate System (x,y,z)
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6. Cartesian (or Rectangular) Coordinate System (x,y,z)
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7. Cartesian (or Rectangular) Coordinate System (x,y,z) 7

8. CIRCULAR / CYLINDRICAL COORDINATE SYSTEM

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The differential volume unit in the circular
cylindrical coordinate system

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SPHERICAL COORDINATE SYSTEM

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





a
a
a
a
a
a
a
a
a
r
r
r







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