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10820黃承彬教授電磁學章節編輯全

10802  電磁學章節編輯全 EL1_A

General information: Course syllabus

Course description

Textbook

Reference

Class notes

Teaching Method

Course comment

Ethics policy

EL1_B

Lesson 1: Introduce to electromagnetism

What is electromagnetism

Basic quantites

Constitutive parameter of materials

EL1_C

Lesson 1: Introduce to electromagnetism

Analysis of EM problems

Background knowledge

EL1_D

Lesson 1: Introduce to electromagnetism

Background knowledge (1)

Background knowledge –Phasor

EL2_A

Lesson 1: Introduce to electromagnetism

Background knowledge (2)

Lesson 2: Transmission Lines 1

Content

What is a transmission line ?

When to view wires as transmission lines

EL2_B

Lesson 2: Transmission Lines 1

Lumped element model of T-Line

Circuit model of T-Line using lumped elements

V, I relationships for R, L, C

Lumped element model for T-Line

EL3_A

Lesson 2: Transmission Lines 1

Transmission line equation

EL3_B

Lesson 2: Transmission Lines 1

Solution to the T-line equations

Reduce unknowns

EL3_C

Lesson 2: Transmission Lines 1

Reduce unknowns

Wave propagation on a TL

The characteristic impedance

Back in time-domain

Back in time-domain: standing waves

EL3_D

Lesson 2: Transmission Lines 2

Lossless T-Lines

Lossless TL circuit and equations

Characteristic parameters of TL

Reflection coefficient

EL4_A

Lesson 2: Transmission Lines 1

Reflection coefficient

Table of reflection coefficients

Standing waves

EL4_B

Lesson 2: Transmission Lines 1

Standing waves

Voltage standing-wave ratio (VSWR, S)

Defined wave impedance

Why knowing wave impedance is helpful?

Input impedance Zin

EL5_A

Lesson 2: Transmission Lines 1

Input impedance Zin

Special cases of loss lines

Short-circuited line

EL5_B

Lesson 2: Transmission Lines 1

Input impedance Zin

Special cases of loss lines

Short-circuited line

EL5_C

Lesson 2: Transmission Lines 1

Impedance matching

EL5_D

Lesson 2: Transmission Lines 1

Example

EL6_A

Lesson 3: Vector Analysis 1

Scalar and vector

Vector algebra

Unit vector

Dot (inner, scalar) product

Cross (vector) product

EL6_B

Lesson 3: Vector Analysis 1

Scalar triple product

Vector triple product

Orthogonal coordinates

-          Definition

-          Application(1)

EL7_A

Lesson 3: Vector Analysis 1

Orthogonal coordinates

-          Application(2)

-          Application(3)

Cartesian coordinate

Cylindrical coordinate

EL7_B

Lesson 3: Vector Analysis 1

Cylindrical coordinate

Coordinate transformation: position

Coordinate transformation: vector

EL7_C

Lesson 3: Vector Analysis 1

Spherical coordinate

Coordinate transformation: position

Coordinate transformation: vector

EL7_D

Lesson 3: Vector Analysis 2

Vector calculus

Overview: derivative of functions

EL8_A

Lesson 3: Vector Analysis 2

Divergence for fun

Divergence: definition & meaning

Divergence formula (1)

EL8_B

Lesson 3: Vector Analysis 2

Divergence formula (2) (3)

Generalized divergence formula

Divergence theorem

EL9_A

Lesson 3: Vector Analysis 2

Curl for fun

Curl: definition & meaning

EL9_B

Lesson 3: Vector Analysis 2

Curl formula

Generalized curl formula

Stokes’ theorem

EL9_C

Lesson 3: Vector Analysis 2

Scalar Laplacian

Vector Laplacian

Two null identities

Lesson 4: Static Electric Fields 1

Conceptual flow chart

Outline

EL9_D

Lesson 4: Static Electric Fields 1

Basic assumptions

The electric field intensity

Two fundamental postulates

The integral forms

EL10_A

Lesson 4: Static Electric Fields 1

Coulomb’s Law

E-field of a single point charge

The definition of Coulomb’s Law

EL10_B

Lesson 4: Static Electric Fields 1

The definition of Coulomb’s Law

If we have a charge distribution?

E-field due to charge distributions (1)

Electric dipole

E-field due to charge distributions (2)

EL11_A

Lesson 4: Static Electric Fields 1

E-field due to charge distributions (2)

Example 3-4

EL11_B

Lesson 4: Static Electric Fields 1

The definition of Gauss’s Law

Example: electric sheltering

Example 3-5(using Gauss’s Law)

Example 3-6

Brief comparison

EL12_A

Lesson 4: Static Electric Fields 1

The definition of electric potential

Physical meaning of electric potential

Electric potential of a point charge

EL12_B

Lesson 4: Static Electric Fields 1

V due to charge distributions

Finding the e-field

Example 3-9

EL12_C

Lesson 4: Static Electric Fields 1

Example 3-8: what is an electric dipole?

The electric field of a dipole

Electric dipole vs. point charge

EL12_D

Lesson 4: Static Electric Fields 2

Classification of materials

Outline

Inside a conductor

Conductor-air interface

Conductor-air interface: boundary conditions

EL13_A

Lesson 4: Static Electric Fields 2

Example 3-11: conducting shell & results

EL13_B

Lesson 4: Static Electric Fields 2

Example 3-11: results

Electric – shielding

Electric dipoles: microscopic view

Electric dipoles: macroscopic view

Metal vs. dielectric

EL14_A

Lesson 4: Static Electric Fields 2

Metal vs. dielectric

How to analyze dipoles?

Polarization surface charge density

Polarization volume charge density

EL14_B

Lesson 4: Static Electric Fields 2

Remarks

Defining the electric flux density (D)

The physical meaning of D, E, P

The dielectric constant

EL15_A

Lesson 4: Static Electric Fields 2

The dielectric constant

Example 3-12: dielectric shell

Boundary condition

EL15_B

Lesson 4: Static Electric Fields 2

Tangential BCs

Normal BCs

Remarks

Example 3-15

Example 3-16

EL15_C

Lesson 4: Static Electric Fields 3

Capacitance and capacitors

Single-conductor capacitor

Example: single conducting sphere

Dual-conductor capacitor

Applying voltage over dual-conductor capacitor

EL15_D

Lesson 4: Static Electric Fields 3

Procedures in determining capacitance

Example 3-17

Example 3-18

Refresh memory

EL16_A

Lesson 4: Static Electric Fields 3

Another method in determining capacitance

Energy of two charges

Energy of more charges

EL16_B

Lesson 4: Static Electric Fields 3

Example 3-22(layer by layer)

Example 3-22(entire sphere already in place)

Electrostatic energy in fields

Example 3-24

EL17_A

Outline

Current density

Convection currents

Conduction current: origin

Conduction current

Ohm’s law

EL17_B

Current laws

Non-conservative field sources

Electromotive force (emf)

Look at KVL again

EL17_C

Equation of continuity

Charge dynamics in conductors

Boundary conditions

Governing equations for current density

Example 5-3: two conducting materials

EL17_D

Example 5-4: parallel plate capacitor

EL18_A

Resistance calculation

Example for leakage resistance between two perfect conductors

Example 5-5: coaxial cable

Lesson 6: Steady Magnetic Fields I

Outline

Fundamental postulates

EL18_B

Lesson 6: Steady Magnetic Fields I

Postulates and physical meanings

Compare E-field with B-field

EL19_A

Lesson 6: Static magnetic fields 1

Example 6-1: Ampere’s circuital law

Example 6-3

EL19_B

Lesson 6: Static magnetic fields 1

Example 6-3

Discuss situation of magnetic field outside

EL19_C

Lesson 6: Static magnetic fields 1

Compare Gauss’s law with ampere’s law

Vector magnetic potential (VMP)

Definition of vector magnetic potential

The need and physical meaning of A

Poisson’s equation

EL19_D

Lesson 6: Static magnetic fields 1

Poisson’s equation

Biot-Savart law and applications

Biot-Savart law: thin wire

Remark

EL20_A

Lesson 6: Static magnetic fields 1

Example 6-4: current-carry wire

Example 6-6: circular current loop

EL20_B

Lesson 6: Static magnetic fields 1

The magnetic dipole

Example 6-7: magnetic dipole

Electric vs. magnetic dipoles

EL21_A

Lesson 6: Static magnetic fields 2

Outline

Static magnetic fields in materials

Induced magnetic dipole

Magnetization vector

A brief comparison

Surface magnetization current density

EL21_B

Lesson 6: Static magnetic fields 2

Current density (in homogenous): simple proof

Volume magnetization current density

Current density (in nonhomogeneous): simple proof

Example 6-8

EL22_A

Lesson 6: Static magnetic fields 2

Magnetic field intensity H

Physical meaning of each term

EL22_B

Lesson 6: Static magnetic fields 2

Physical meaning of each term

Brief comparison (E, B), (D, H)

Magnetic susceptibility

EL22_C

Lesson 6: Static magnetic fields 2

Example 6-10: magnetic circuit

EL22_D

Lesson 6: Static magnetic fields 2

Magnetic flux

Classification of magnetic materials

Diamagnetic material

Paramagnetic material

Ferromagnetic material

EL23_A

Lesson 6: Static magnetic fields 2

Boundary conditions

Normal boundary condition

Tangential boundary condition

Example 6-12(Js=0)

Magnetic leakage

EL23_B

Lesson 6: Static magnetic fields 2

Magnetic leakage

EL24_A

Lesson 6: Static magnetic fields 3

Inductance

Defining self-inductance

Defining mutual-inductance

When can we ignore mutual-inductance ?

Comment

EL24_B

Lesson 6: Static magnetic fields 3

Evaluating inductance: method 1

Example 6-15

Example 6-18

Magnetic energy of a single loop

Magnetic energy of two loops

Magnetic energy of N loops

EL24_C

Lesson 6: Static magnetic fields 3

Magnetic energy of N loops

Magnetic energy of field quantities

Evaluating inductance: method 2

Example 6-20

Force on current carrying loop

Suppose we have two loops

EL24_D

Lesson 6: Static magnetic fields 3

Example 6-21

Magnetic torque

EL25_A

Lesson 7: Time-Varying fields 1

Overview

Outline

Modifying fundamental postulate

What does the E in the equation mean?

EL25_B

Lesson 7: Time-Varying fields 1

Physical meanings

Stationary circuit in time-varying M-field

Example 7-1

Comment

EL26_A

Lesson 7: Time-Varying fields 1

Transformer

Ideal transformer

EL26_B

Lesson 7: Time-Varying fields 1

Moving circuit in a static M-field

Example 7-3

Moving circuit in a time-vary M-field

Example 7-4: AC generator

EL26_C

Lesson 7: Time-Varying fields 1

Brief summary

James Clerk Maxwell

Contribution of Maxwell

Modified Ampere’s law

Maxwell’s contribution: physical sense

Example 7-5: ac-driven capacitor

Maxwell’s equations

Tangential BC of dynamic (E, M)-fields

EL27_A

Lesson 7: Time-Varying fields 2

Outline

Time-domain Maxwell’s equations

EL27_B

Lesson 7: Time-Varying fields 2

Time-domain Maxwell’s equations

Time-domain homogeneous wave equation

Compared to lossless T-Lines

EL28_A

Lesson 7: Time-Varying fields 2

Why time-harmonics?

Scalar to vector phasor notation

Frequency-domain Maxwell’s equation

Wave vector, wavelength, frequency

Phasor-domain: compared to lossless T-Lines

Waves in lossy medium: complex permittivity

Complex permittivity > complex wave number

EL28_B

Lesson 7: Time-Varying fields 2

Example: moist ground and gold

The EM spectrum

Polarized and unpolarized media

Induced polarization in dielectric media

Inhomogeneous wave equation

Source of EM Waves

EL28_C

Lesson 7: Time-Varying fields 2

Time-varying e-dipole

Light propagation in medium

EL28_D

Lesson 7: Time-Varying fields 2

Place waves

Solution to scalar Helmholtz’s equation