CalvinCollege - Engineering Department

Engineering 302 - Electromagnetic Fields

Spring 2005

An Independent Study Approach

Professor: Paulo F. Ribeiro, SB134 X6407,

Text: Engineering Electromagnetics, Sixth Edition, by William Hayt, and John A. Buck, McGraw Hill Book Company, New York, 2001

“The beauty of electricity . . . [is] that it is under law.” Michael Faraday

“Each individual man should do all he can to impress his mind with the extent , the order, and the unity of the universe, and should carry these ideas with him as he reads [the Bible].”

James Clerk Maxwell

Course Title: Electromagnetic Fields

Course Goals and Objectives:

This course uses Maxwell's equation as the central theme. These equations are developed from a historical approach in which the relevant experimental laws are gradually introduced and manipulated with the help of a steadily increasing knowledge of vector calculus. The equations are developed in their differential and integral forms to free space and material region. Several applications of these equations are studied, including wave motion, skin effect, transmission line phenomena, circuit theory, and resonant cavity. A first look at radiation and antennas is also included.

The. objective of the course is then to develop physical insight into applications of electromagnetic equations and to gain facility in doing calculations in solving problems in electromagnetic theory.

The electromagnetic spectrum ranges from frequencies 10 E+23 cycles per second to 0 cycles per second (or, in corresponding wavelengths, from 10 E13 centimeter to infinity) and including, in order of decreasing frequency, cosmic ray photons, gamma rays, xrays, ultraviolet radiation, visible light, infrared radiation, microwaves, radio waves, heat, and electric currents. Thus, one can very easily see the importance of a clear understanding of electromagnetic fields in the process of redeeming, i.e. preserving, healing and opening up, creation.

The concept of a field (and corresponding forces) introduced by Maxwell (and Kelvin) is a basic and fruitful idea to describe physical (electromagnetic) interactions. From a philosophical point of view (and within a Dooryerweerdian framework) a field is a spatial concept which anticipates the kinematical and physical modal aspects, whereas force is a physical concept, as it refers back to the spatial aspect. From this kind of reasoning we hope to encourage the students to think and develop a creative, scientific/philosophical mind in which the applications (and implications) of the Maxwell's equations may be understood and discussed. Students are exposed to a brief introduction to numerical methods / finite elements for electromagnetic applications.

Course Description and Overview:

The course will cover the topics of: vector analysis review, coulomb's law and electric field intensity, electric flux density, Gauss's law, divergence, energy and potential, conductors, dielectrics, capacitance, Poisson's and Laplace's equations, the steady magnetic field,. magnetic forces, materials, inductance, timevarying fields, Maxwell's equations, the uniform plane wave, transmission lines and other applications.

Considering the abstract nature of the subject, visual aids are very important in grasping concepts. Consequently, in order to facilitate the learning process, an emphasis on computer calculations will given through the extensive use of MathCAD, MATLAB, and Mathematica. Also finite element computer programs for calculation of electrical and magnetic fields will be used.

Course Outline and Schedule:

Methods of Instruction: Four class periods (two class presentations and two computer lab hours) per week.

Major assignments or Projects: weekly homework, computer-lab/research paper project.

Means of Evaluation:Homework(40%)

Research Paper / Presentation (60%)

Example of Topics for Research Paper:

X-ray

Biological Effect of EM Fields: power, RF, etc.

Electromagnetic Interference

Magnetic Fields at Home

Electric Blankets

Geomagnetic Disturbances on Power Systems

History / Philosophy of EMF

Previous Papers
Electromagnetic Pulse
Rail guns

Microwaves

The Effects of Electromagnetic Radiation on Health in Space Environments
DC Stepping Motors
The History of Electromagnetism
Biological Effects of EMF
Particle Accelerators

Wireless Communications

Magnetic Levitation

The HAARP Project

Geomagnetic Storms and Impact on Power Systems

Proceedings of the Spring 2004 Course

Computational Tools Used: MathCAD, MATLAB, Quick Field, Algor, etc.

COURSE OUTLINE AND SCHEDULE

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Lecture / Lab

SB 120 Lecture Topic Read Chpt.
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Grading System, Homework/Papers/Project1

Policy.

Introduction

Vector Analysis, Scalars and Vectors, Vector Algebra

The Cartesian Coordinate System

Vector Components and Unit Vector, The Vector Field,

The Dot Product, The Cross Product

Other Coordinate Systems: Circular Cylindrical, The Spherical Coordinate

Coulomb's Law:2

The Experimental Law of Coulomb, Electric Field Intensity

Field of n Point Charges, Field Due to a Continuous Volume Charge Distribution

Field of a line Charge, Field of a Sheet of Charge

Streamlines and Sketches of Fields

Electric Flux Density, Gauss's Law, and 3

Divergence, Electric Flux Density, Gauss' Law

Application of Gauss's Law, Maxwell's First equation (Electrostatics)

The Vector Operand and the Divergence Theorem

Energy and Potential:4

Energy Expanded in Moving a Point Charge in an Electric Field

The Line Integral, Definition of Potential Difference and Potential

The Potential Field of a Point Charge

The Potential Field of a System of Charges: Conservative Property

Potential Gradient, The Dipole

Energy Density in The Electrostatic Field

Conductors, Dielectrics, and Capacitance: 5

Current and Current Density, Continuity of Current, Metallic Conductors

Conductor Properties and Boundary Conditions

The Method of Images, Semiconductors, The Nature of Dielectric Materials

Boundary Conditions for Perfect Dielectric Materials, Capacitance

Several Capacitance Examples

Poisson's and Laplace's Equations:7

Poisson's and Laplace's Equations, Uniqueness Theorem

Example of the Solution of Poisson's Equation

Example of the Solution of Laplace's Equation

Product Solution of Laplace's Equation

The Steady Magnetic Field:8

BiotSavart Law, Ampere's Circuit Law, Curl, Stokes' Theorem

Magnetic Flux and Magnetic Density, The Scalar and Vector Magnetic Potentials

Derivation of SteadyMagneticField Laws

Magnetic Forces, Materials, and Inductance: 9

Force on Moving Charge, Force on a Differential Current Element

Force between Differential Current Elements

Force and Torque on a Closed Circuit, The Nature of Magnetic Materials

Magnetization and Permeability, Magnetic Boundary Conditions

The Magnetic Circuit, Potential Energy and Forces on Magnetic Fields

Inductance and Mutual Inductance

TimeVarying Fields and Maxwell's Equations: 10

Faraday's Law, Displacement Current, Maxwell's Equation in Integral Form

The Retarded Potentials

The Uniform Plane Wave 11

Wave Motion in Free Space, Wave Motion in Perfect Dielectrics

The Poynting and Power Considerations

Propagation in Good Conductors: Skin Effect

Reflection of Uniform Plane Waves, StandingWave Ratio

Transmission Lines Equations: 13

Antenna Fundamentals 14

Philosophical Perspectives: open discussion

HOMEWORK ASSIGNMENTS
Chapter / Problems
1 / 5, 12, 15, 23, 27
2 / 3, 7, 10, 13, 17, 20
3 / 3, 9, 12, 15, 17, 21, 26
4 / 6, 9, 11, 13, 17, 23, 31, 33
5 / 1, 3, 9, 17, 23, 29, 45
7 / 3, 13, 17, 23, 27
8 / 1, 5, 15, 23, 29
9 / 5, 9, 31a,b
10 / 3, 9, 15
11 / 3, 9, 21, 25
13 / MathCAD Equations Summary and Applications

All homework assignments must be turned in on time for full credit. Late assignments will be assessed a penalty. Assignments more than one week late will be assessed a penalty. Homework, Tests, etc. should be prepared electronically (MathCAD, MATLAB / Mathematica, Word).

No handwritten assignments will be accepted.