This document covers Chapter 5 of a textbook on electromagnetic field theory for second year electrical engineering students. The chapter discusses stationary magnetic fields, including the force on moving charges and current-carrying conductors, generation of magnetic fields, boundary conditions, vector and scalar magnetic potentials, Ampere's law, the Biot-Savart law, magnetic torque, dipoles, magnetization in materials, inductors, inductance, and magnetic energy. Key topics include defining magnetic dipoles using small current loops or magnets, explaining magnetization as the alignment of magnetic moments in a material by an external magnetic field, and classifying magnetic materials as diamagnetic, paramagnetic or ferromagnetic based on their relative permeability.

1. Electromagnetic Field Theory
2nd Year EE Students
Prof. Dr. Magdi El-Saadawi
www.saadawi1.net
saadawi1@gmail.com
2014/2015

2. Chapter 5
Stationary Magnetic Fields
(Magnetostatics)

3. Chapter 5 Stationary Magnetic Fields
5.1. Introduction
5.2. Force on a Moving Charge
5.3. Force on a Current-Carrying Conductor in an External Magnetic Field
5.4 Generation of a Magnetic Field
5.5. Boundary Conditions for the Magnetic Induction
5.6. Vector Potential of the Magnetic Field
5.7. The Magnetic Field Intensity (Magnetic Excitation)
5.8. Field Equation and Boundary Conditions for Magnetic Field Intensity

4. 5.9. Applications of Ampere’s Law 5.10. The Nature of Magnetic Materials
5.10. The Nature of Magnetic Materials
5.11. General Solution of Stationary Magnetic Fields
5.12. Biot-Savart Law
5.13. The Scalar Magnetic Potential
5.14 Magnetic Torque and Moment
5.15. Magnetic Dipole
5.16. Magnetization in Materials
5.17. Inductors and Inductances
5.18. Magnetic Energy
5.19 Magnetic CircuitsChapter 5 Stationary Magnetic Fields

5. A small current loop or a short permanent magnet can be considered as a magnetic dipole.
5.16 Magnetization in Materials

6. To understand Magnetization in the Materials, let’s first discuss what happen in the entire of the material.
An internal magnetic field is produced by electrons orbiting around the nucleus as in Fig. 5.17 a 5.16 Magnetization in Materials

7. Both of these electronic motions produce internal magnetic fields B, that are similar to the magnetic field produced by a current loop (Fig. c.) with a magnetic moment of

8. Without an external Bfield applied to the material, the sum of m's is zero due to random orientation as in Fig. 5.18 (a).
When an external Bfield is applied, the magnetic moments of the electrons more or less align themselves with Bso that the net magnetic moment is not zero as in Fig. 5.18 (b). 5.16 Magnetization in Materials

9. 5.16 Magnetization in Materials

10. 5.16 Magnetization in Materials

11. 5.16 Magnetization in Materials

12. 5.16 Magnetization in Materials

14. 5.16 Magnetization in Materials

15. 5.16 Magnetization in Materials

16. Magnetic materials can be roughly classified into three main groups in accordance with their μr: Diamagnetic, Paramagnetic, Ferromagnetic.
5.10. The Nature of Magnetic Materials

17. 5.10. The Nature of Magnetic Materials

19. 5.10. The Nature of Magnetic Materials

20. 5.10. The Nature of Magnetic Materials

21. 5.17 Inductors and Inductances

22. 5.17 Inductors and Inductances

23. 5.17 Inductors and Inductances

24. 5.17 Inductors and Inductances

25. 5.17 Inductors and Inductances

26. 5.17 Inductors and Inductances

28. 5.17 Inductors and Inductances

29. 5.17 Inductors and Inductances

30. 5.18. Magnetic Energy

31. 1. Determine the self-inductance of a coaxial cable of inner radius a and outer radius bProblems

32. Problems

33. Problems

34. Problems