Electromagnetics Introduction

Electromagnetics

the study of electricity, magnetism, and light

Electromagnetics

the study of the effect of charges at rest and charges in motion.

Electromagnetics

study of electromagnetic phenomena

Maxwell's Equations

a set of four equations that describe electromagnetic phenomena. a central concept of electromagnetism

Circuit Theory

it focuses on low frequencies like electrical circuits

Electromagnetic Theory

it focuses on high frequencies like signals, transmission and waves

Iodestone

a piece of magnetite that naturally acts as a magnet

Thales 600 B.C.

first observed that if amber is rubbed with fur, amber is able to pick light objects like dust

Shen Kuo 11th century

first person to write about the magnetic needle compass

Peter Peregrinus 13th century

discovered the fundamental properties of magnets; regardless of the shape, magnets always have two poles.

Gerolano Cardano 1550

first to distinguish between electrical and magnetic forces

William Gilbert 1600

physician during the time of Queen Elizabeth. he was able to show that many other substances can be electrified. theorized that earth is a giant magnet

Thomas Browne

first to use "electricity" in his Pseudodoxia Epodemica

Otto von Guericke 1663

developed primitive electrostatic generator, a machine that can generate electricity by means of friction

Robert Boyle 1675

He discovered that objects electrified in vacuum would attract light objects

Stephen Gray 1729

Discovered the difference between conductors and insulators

Charles du Fay 1737

Discovered the existence of two types of electricity; the vitreous that is generated from rubbing glass and resinous that is produced by rubbing resin

von Kleist 1744

developed the Leyden Jar

Musschenbroek 1745

invented his own Leyden Jar

William Watson 1747

discovered that a discharge of static electricity produces electric current

Benjamin Franklin 1752

performed the famous experiment that involves flying a kite on a rather stormy day

Benjamin Franklin 1752

invented the lightning rod

Charles Coulomb 1785

discovered that the force between small, charged bodies varies inversely as the square of the distance between the bodies

Luigi Galvani 1790

animal electricity

Allesandro Volta 1799

developed the first battery called voltaic pile in 1799

Voltaic Pile/Battery

made of alternating copper and zinc piled up an separated by brine-soaked cloth

Hans Christian Oersted 1819

He noticed that a compass needle was deflected when it was placed close to current carrying conductor

Andre-Marie Ampere 1820

He discovered that parallel current carrying conductor exert forces towards each other. His name is now used in units of electric current

Ampere's Law

describe the force between two current carrying elements

Georg Simon Ohm 1826

discovered the relationship between electromotive force and electric current. his name is the unit of resistance

Michael Faraday

English chemist who created the first simple electric motor and the first dynamo

Michael Faraday

discovered the law of electromagnetic induction

Diamagnetism

discovered in 1845 by Faraday, the phenomenon wherein substances like copper, zinc, bismuth are slightly repelled by magnet

Faraday effect

rotation of the plane of polarization of a light beam by a magnetic field

Joseph Henry 1832

invented the first electric rely unit of inductance after his name discovered the phenomenon of self-induction

Fizeau and Foucault 1849

determined the speed of light C=299,792.458 km/sec

Gustav Robert Kirchhoff 1854

famous law which are the consequences of the laws of conservation of charge and energy

James Clark Maxwell

he formulated 20 differential equations that describe all known laws of electricity and magnetism

James Clark Maxwell

he introduced the idea of displacement current, modified Amperes Law

A Dynamical Theory of Electromagnetic Field

in this paper, Maxwell derived electromagnetic wave equation that describe the possibility of the existence of an oscillating electric magnetic field that travels in free space in the form of waves

James Clark Maxwell

light afterall is an electromagnetic phenomenon, has the same nature as electricity and magnetism

Albert Einstein

described Maxwell's work as the most profound and most fruitful that physics has experienced since the time of Newton

Oliver Heaviside 1884

reduced the original Maxwell's equations into set of four partial differential equations

Heinrich Hertz 1887

his discovery of actual existence of electromagnetic waves confirmed the prediction of Maxwell

Heinrich Hertz

He did not realize the application of his discovery as proving Maxwell's prediction is more important to him

radio waves

EM waves that Hertz discovered

Guglielmo Marconi

developed wireless telegraphy- the first practical application of radio waves communication system

Guglielmo Marconi

Father of Wireless

JJ Thomson 1897

discovered the electron in his experiments using cathode ray tube

cathode rays

made of very tiny particles, smaller than atoms that possess negative charge — known as electrons.

Generator

mechanical energy to electrical energy

Electric motor/Dynamo

electrical energy to mechanical energy

Antennas

transducers that converts electric signals to radiowaves

Optical Fibers

serve as the backbone of internet globally

elektron

greek word for amber

Leyden Jar

very first capacitor

Charles Coulomb

performed experiment using torsion balance

Michael Faraday

greatest experimentalist of all time

flux

lines of force emanating from charged bodies and magnets

Farad

unit of capacitance

“On Faraday’s Lines of Force”

contains explanation of the relationship between electricity and magnetism

“On Physical Lines of Force”

contains the 20 Differential Equations of Maxwell