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Electromagnetic Theory
             2012 - 2011



       Dr. Omed Ghareb Abdullah
         University of Sulaimani
Faculty of Science and Science Education
 School of Science / Physics Department
Electromagnetic Theory Lectures
on webpage of University of Sulaimani
  http://www.univsul.org
  Faculties
  School of Science
  Departments or Branches
  Department of Physics
  Department staff
  http://www.univsul.org/E_U_Mamosta.aspx?Jimare=84&Ziman=2
Course Reading list and References
Main References:
 [1] David J. Griffiths, and Reed College, “Introduction to Electrodynamics”,
     Prentice-Hall, Inc. (1999).
 [2] Matthew N. O. Sadiku, “Elements of Electromagnetics”, Fourth Edition,
     Oxford University Press, Inc., (2007).

Useful References:
  [3] Herbert P. Neff, “Introductory Electromagnetics”, John Wiley & Sons,
      Inc., (1991).
  [4] Joseph A. Edminister, “Schaum’s outline of Theory and Problems of
      Electromagnetis”, Second Edition, The McGraw-Hill Companies, Inc.
      (1993).
  [5] Fawwaz T. Ulaby, “Fundamentals of Applied Electromagnetics”, (2004).
  [6] Stuart M. Wentworth, “Fundamentals of Electromagnetics With
      Engineering Application”, (2005).
  [7] http://home.att.net/~numericana/answer/maxwell.htm
Syllabus for 1st and 2nd Semester
Chapter One: Vector Analysis and Coordinate
               Systems
Chapter Two: Electrostatic Fields
Chapter Three: Special Techniques
Chapter Four: Electrostatic Field in Matter
Chapter Five: Magnetostatics Field
Chapter Six: Magnetic Fields in Matter
Chapter Seven: Electrodynamics Fields
Chapter Eight: Electromagnetic Waves Propagation
Branches of electromagnetic spectrum in terms of their
             frequencies, wavelengths and energies

No.       Branches
1.       Cosmic Ray
2.       Gamma Ray

3.          X-Ray

4.       Ultra Violet

5.       Visible light
6.         Infrared

7.       Microwave


8.       Radio Wave
Branches of electromagnetic spectrum in terms of their
       frequencies, wavelengths and energies
Multiple and submultiples prefixes

 Prefix        Symbol     Magnitude
  exa            E           1018
  peta           P           1015
  tera           T           1012
  giga           G           109
  mega           M           106
  kilo           K           103
  milli          m           10-3
 micro           μ           10-6
  nano           n           10-9
  pico           p           10-12
  fimto          f           10-15
  atto           a           10-18
 Electromagnetic Theory: Is a science which studies the
  electric and magnetic        phenomenon      with   their
  engineering applications.

 Wave: Generally the wave is defined as a form of energy
  in move.

 Field: Is defined as the action at a distance between two
  objects without direct contact, such as Electric,
  Magnetic and Gravitational fields.
 Electrostatics Field: Stationary charges produce E-field. This field
  and their phenomenon’s have been studied by many scientists:
  Coulomb, Ohm, Gauss, Kirschofe and Volta.

 Magnetostatics Field: Moving charges or stationary current lead
  to the production of magnetic field. This field and their
  phenomenon’s have been studied by many scientists: Oerestd,
  Ampere, Biot-Savart, Henry, Lenz, Lorentz and Faraday.

 Electromagnetic Field: Time varying current or when the charge
  is accelerated (i.e. moving with varying velocity) the field which
  produced is known as electromagnetic field. This theory has
  been constructed by Maxwell who unified the theory of
  electricity and magnetism through a set of four equations
  known as the Maxwell’s equations.
       ρ
             E
                   o
                       
                     B
           E
                       t
          
           B 0
                                       
                                    E
           B   oJ           o      o
                                       t
E   Electric field Intensity ( N / C ) or (V / m)
B   Magnetic flux density ( Web / m 2 )
    Ch arg e density ( C / m 3 )
J   Current density ( A / m 2 )
History of Electric and Magnetic Phenomenon
1. ca. 900 Legend has it that while walking across a field in northern Greece, a
   shepherd named Magnus experiences a pull on the iron nails in his sandals
   by the black rock he was standing on. The region was later named
   Magnesia and the rock became known as magnetite [a form of iron with
   permanent magnetism].

2. ca. 600 Greek philosopher Thales describes how amber, after being rubbed
   with cat fur, can pick up feathers [static electricity].

3. ca. 1000 Magnetic compass used as a navigational device.

4. 1600 William Gilbert (English) coins the term electric after the Greek word
   for amber (elektron), and observes that a compass needle points north-
   south because the Earth acts as a bar magnet.

5. 1671 Isaac Newton (English) demonstrates that white light is a mixture of
   all the colors.

6. 1733 Charles-Francois du Fay (French) discovered that electric charges are
   of two forms, and that like charges repel and unlike charges attract.

7. 1745 Pieter van Musschenbroek (Dutch) invents the Leyden jar, the first
   electrical capacitor.
8. 1752 Benjamin Franklin (American) invents the lightning rod and
   demonstrates that lightning is electricity.

9. 1785 Charles-Augustin de Coulomb (French) demonstrates that the
   electrical force between charges is proportional to the inverse of the
   square of the distance between them.

10. 1800 Alessandro Volta (Italian) develops the first electric battery.

11. 1820 Hans Christian Oersted (Danish) demonstrates the interconnection
   between electricity and magnetism through his discovery that an electric
   current in a wire causes a compass needle to orient itself perpendicular
   to the wire.

12. 1820 Andre-Marie Ampere (French) notes that parallel currents in wires
   attract each other and opposite currents repel.

13. 1820 Jean-Baptiste Biot (French) and Felix Savart (French) develop the
   Biot-Savart law relating the magnetic field induced by a wire segment to
   the current flowing through it.

14. 1827 Georg Simon Ohm (German) formulates Ohm’s law relating electric
   potential to current and resistance.
15. 1827 Joseph Henry (American) introduces the concept of inductance and built one
    of the earliest electric motors. He also assisted Samuel Morse in the development of
    the telegraph.

16. 1831 Michael Faraday (English) discovers that a changing magnetic flux can induce
    an electromotive force.

17. 1835 Carl Friedrich Gauss (German) formulates Gauss’s law relating the electric flux
    flowing through an enclosed surface to the enclosed electric charge.

18. 1873 James Clerk Maxwell (Scottish) publishes his Treatise on Electricity and
    Magnetism in which he unites the discoveries of Coulomb, Oersted, Ampere,
    Faraday, and others into four elegantly constructed mathematical equations known
    today as Maxwell’s Equations.

19. 1887 Heinrich Hertz (German) builds a system that can generate electromagnetic
    waves (at radio frequencies) and detect them.

20. 1888 Nikola Tesla (Serbian-American) invents the ac (alternating current) electric
    motor.

21. 1895 Wilhelm Roentgen (German) discovers Xrays. One of his first X-ray images
    was of the bones in his wife’s hand. [1901 Nobel Prize in physics.]

22. 1897 Joseph John Thomson (English) discovers the electron and measures its
    charge-to-mass ratio. [1906 Nobel Prize in physics.]

23. 1905 Albert Einstein (German-American) explains the photoelectric effect
   discovered earlier by Hertz in 1887. [1921 Nobel Prize in physics.]

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Electro 0

  • 1. Electromagnetic Theory 2012 - 2011 Dr. Omed Ghareb Abdullah University of Sulaimani Faculty of Science and Science Education School of Science / Physics Department
  • 2. Electromagnetic Theory Lectures on webpage of University of Sulaimani http://www.univsul.org Faculties School of Science Departments or Branches Department of Physics Department staff http://www.univsul.org/E_U_Mamosta.aspx?Jimare=84&Ziman=2
  • 3. Course Reading list and References Main References: [1] David J. Griffiths, and Reed College, “Introduction to Electrodynamics”, Prentice-Hall, Inc. (1999). [2] Matthew N. O. Sadiku, “Elements of Electromagnetics”, Fourth Edition, Oxford University Press, Inc., (2007). Useful References: [3] Herbert P. Neff, “Introductory Electromagnetics”, John Wiley & Sons, Inc., (1991). [4] Joseph A. Edminister, “Schaum’s outline of Theory and Problems of Electromagnetis”, Second Edition, The McGraw-Hill Companies, Inc. (1993). [5] Fawwaz T. Ulaby, “Fundamentals of Applied Electromagnetics”, (2004). [6] Stuart M. Wentworth, “Fundamentals of Electromagnetics With Engineering Application”, (2005). [7] http://home.att.net/~numericana/answer/maxwell.htm
  • 4. Syllabus for 1st and 2nd Semester Chapter One: Vector Analysis and Coordinate Systems Chapter Two: Electrostatic Fields Chapter Three: Special Techniques Chapter Four: Electrostatic Field in Matter Chapter Five: Magnetostatics Field Chapter Six: Magnetic Fields in Matter Chapter Seven: Electrodynamics Fields Chapter Eight: Electromagnetic Waves Propagation
  • 5. Branches of electromagnetic spectrum in terms of their frequencies, wavelengths and energies No. Branches 1. Cosmic Ray 2. Gamma Ray 3. X-Ray 4. Ultra Violet 5. Visible light 6. Infrared 7. Microwave 8. Radio Wave
  • 6. Branches of electromagnetic spectrum in terms of their frequencies, wavelengths and energies
  • 7. Multiple and submultiples prefixes Prefix Symbol Magnitude exa E 1018 peta P 1015 tera T 1012 giga G 109 mega M 106 kilo K 103 milli m 10-3 micro μ 10-6 nano n 10-9 pico p 10-12 fimto f 10-15 atto a 10-18
  • 8.  Electromagnetic Theory: Is a science which studies the electric and magnetic phenomenon with their engineering applications.  Wave: Generally the wave is defined as a form of energy in move.  Field: Is defined as the action at a distance between two objects without direct contact, such as Electric, Magnetic and Gravitational fields.
  • 9.  Electrostatics Field: Stationary charges produce E-field. This field and their phenomenon’s have been studied by many scientists: Coulomb, Ohm, Gauss, Kirschofe and Volta.  Magnetostatics Field: Moving charges or stationary current lead to the production of magnetic field. This field and their phenomenon’s have been studied by many scientists: Oerestd, Ampere, Biot-Savart, Henry, Lenz, Lorentz and Faraday.  Electromagnetic Field: Time varying current or when the charge is accelerated (i.e. moving with varying velocity) the field which produced is known as electromagnetic field. This theory has been constructed by Maxwell who unified the theory of electricity and magnetism through a set of four equations known as the Maxwell’s equations.
  • 10.  ρ E o    B E t   B 0     E B oJ o o t E Electric field Intensity ( N / C ) or (V / m) B Magnetic flux density ( Web / m 2 ) Ch arg e density ( C / m 3 ) J Current density ( A / m 2 )
  • 11. History of Electric and Magnetic Phenomenon 1. ca. 900 Legend has it that while walking across a field in northern Greece, a shepherd named Magnus experiences a pull on the iron nails in his sandals by the black rock he was standing on. The region was later named Magnesia and the rock became known as magnetite [a form of iron with permanent magnetism]. 2. ca. 600 Greek philosopher Thales describes how amber, after being rubbed with cat fur, can pick up feathers [static electricity]. 3. ca. 1000 Magnetic compass used as a navigational device. 4. 1600 William Gilbert (English) coins the term electric after the Greek word for amber (elektron), and observes that a compass needle points north- south because the Earth acts as a bar magnet. 5. 1671 Isaac Newton (English) demonstrates that white light is a mixture of all the colors. 6. 1733 Charles-Francois du Fay (French) discovered that electric charges are of two forms, and that like charges repel and unlike charges attract. 7. 1745 Pieter van Musschenbroek (Dutch) invents the Leyden jar, the first electrical capacitor.
  • 12. 8. 1752 Benjamin Franklin (American) invents the lightning rod and demonstrates that lightning is electricity. 9. 1785 Charles-Augustin de Coulomb (French) demonstrates that the electrical force between charges is proportional to the inverse of the square of the distance between them. 10. 1800 Alessandro Volta (Italian) develops the first electric battery. 11. 1820 Hans Christian Oersted (Danish) demonstrates the interconnection between electricity and magnetism through his discovery that an electric current in a wire causes a compass needle to orient itself perpendicular to the wire. 12. 1820 Andre-Marie Ampere (French) notes that parallel currents in wires attract each other and opposite currents repel. 13. 1820 Jean-Baptiste Biot (French) and Felix Savart (French) develop the Biot-Savart law relating the magnetic field induced by a wire segment to the current flowing through it. 14. 1827 Georg Simon Ohm (German) formulates Ohm’s law relating electric potential to current and resistance.
  • 13. 15. 1827 Joseph Henry (American) introduces the concept of inductance and built one of the earliest electric motors. He also assisted Samuel Morse in the development of the telegraph. 16. 1831 Michael Faraday (English) discovers that a changing magnetic flux can induce an electromotive force. 17. 1835 Carl Friedrich Gauss (German) formulates Gauss’s law relating the electric flux flowing through an enclosed surface to the enclosed electric charge. 18. 1873 James Clerk Maxwell (Scottish) publishes his Treatise on Electricity and Magnetism in which he unites the discoveries of Coulomb, Oersted, Ampere, Faraday, and others into four elegantly constructed mathematical equations known today as Maxwell’s Equations. 19. 1887 Heinrich Hertz (German) builds a system that can generate electromagnetic waves (at radio frequencies) and detect them. 20. 1888 Nikola Tesla (Serbian-American) invents the ac (alternating current) electric motor. 21. 1895 Wilhelm Roentgen (German) discovers Xrays. One of his first X-ray images was of the bones in his wife’s hand. [1901 Nobel Prize in physics.] 22. 1897 Joseph John Thomson (English) discovers the electron and measures its charge-to-mass ratio. [1906 Nobel Prize in physics.] 23. 1905 Albert Einstein (German-American) explains the photoelectric effect discovered earlier by Hertz in 1887. [1921 Nobel Prize in physics.]