Electromagnetism Lecture#1 [Introduction] Instructor: Engr. Muhammad Mateen Yaqoob

ElectromagnetismLecture#1 [Introduction]

Instructor:

Engr. Muhammad Mateen Yaqoob

MATEEN YAQOOB DEPARTMENT OF COMPUTER SCIENCE

Instructor Information Instructor:

Engr. Muhammad Mateen Yaqoob

[email protected]

Consulting Hours:

Tuesday (9:30 am – 3:30 pm)

Faculty Block 2nd Floor (304-4)


Instructor Introduction MS Electrical Engineering

COMSATS Islamabad

BS Telecommunication Engineering

Foundation University Islamabad

Area of Interest:

Wireless Communication and Networks


Course Introduction (1/2) This course is worth 3 credit hours

Prerequisites:

A good grounding in calculus and physics is essential for this course

Course Focus:

The focus of course is on electricity and magnetism, including electric fields, magnetic fields and laws, electromagnetic forces, conductors and dielectrics, and electromagnetic waves.


Course Introduction (2/2) Text-book:

Physics for Scientists and Engineers by Serway/Jewett (6th and higher editions)

Recommended Book:

Principles of Electric Circuits (Conventional Current Version) by Thomas L. Floyd

Field and Wave Electromagnetics by David K. Cheng

Lecture notes will be available to students from my webpage (www. mateen.yolasite.com)


Course Grading Mid-Term Exam = 25 Marks

Sessional = 20 Marks

Lab = 10 Marks

Final-Term Exam = 45 Marks


Coordinate Systems Many aspects of physics involve a description of a location in space

Cartesian coordinate system:◦ Also called rectangular coordinates◦ In this horizontal and vertical axes intersect at a point defined as the origin

Polar coordinate system:◦ Sometimes it is more convenient to represent a point in a plane by its plane

polar coordinates (r, θ)◦ In this polar coordinate system, r is the distance from the origin to the point

having Cartesian coordinates (x, y), and θ is the angle between a line drawn from the origin to the point and a fixed axis

◦ This fixed axis is usually the positive x axis, and θ is usually measured counterclockwise from it

Cartesian Coordinate System

Polar Coordinate System


Coordinate Systems Therefore, starting with the plane polar coordinates of any point, we can obtain the Cartesian coordinates by using the equations

Furthermore, the definitions of trigonometry tell us that

If the reference axis for the polar angle θ is chosen to be one other than the positive x axis or if the sense of increasing θ is chosen differently, then the expressions relating the two sets of coordinates will change

The right triangle used to relate (x, y) to (r, θ)


Physical Quantities Scalar: Certain physical quantities only have magnitude e.g., mass or the absolute temperature

These quantities can be represented by numbers alone

Vector: Those which have both magnitude and direction

The magnitude can stretch or shrink, and the direction can reverse

Position, displacement, velocity, acceleration, force, momentum and torque are all physical quantities that can be represented mathematically by vectors



Properties of Vector A vector is a quantity that has both direction and magnitude

Let a vector be denoted by the symbol

The magnitude of is

We can represent vectors as geometric objects using arrows

The length of the arrow corresponds to the magnitude of the vector

The arrow points in the direction of the vector


Vector Addition Vectors can be added using “Head-to-tail rule”


Vector Addition Vector addition satisfies the following four properties:

1. Commutivity: The order of adding vectors does not matter

2. Associativity: When adding three vectors, it doesn’t matter which two you start with

3. Identity Element for Vector Addition: There is a unique vector, that acts as an identity element for vector addition

4. Inverse element for Vector Addition: For every vector, there is a unique inverse vector


Standards of Length, Mass, and Time











Units of measurement

SI fundamental units

SI supplementary units


Except for current which is a fundamental unit, all electrical and magnetic units are derived from the fundamental units.

Electrical quantities and derived units with SI symbols.

Electric Quantities and Units


Units of measurement

Magnetic quantities and derived units with SI symbols.

Magnetic quantities and Units


Scientific Notation Very large and very small numbers are represented with scientific Notation.

In scientific notation, a quantity is expressed as a product of a number between 1 and 10 and a power of ten (10x).

For Example

47,000,0.0 = 4.7 x 105

0.00022 = 2.2 x 10-4


Power of Ten


ExamplesQ 1


Q 2

Examples


ExamplesQ 3


Engineering Notation Engineering notation is similar to scientific notation. However, in engineering notation a number can have from one to three digits to the left of the decimal point and the power-of-ten exponent must be a multiple of three.


Examples

Q 1


ExamplesQ 2


Metric Prefixes In engineering notation metric prefixes represent each of the most commonly used powers of ten.


Examples

Q 1


Metric Unit Conversion When converting from a larger unit to a smaller unit, move the decimal point to the right. Remember, a smaller unit means the number must be larger.


Metric Unit Conversion When converting from a smaller unit to a larger unit, move the decimal point to the left. Remember, a larger unit means the number must be smaller.


Metric Unit Conversion

Q 1


ExamplesQ 2

Documents

Electromagnetism Lecture#1 [Introduction] Instructor: Engr. Muhammad Mateen Yaqoob