Text/References 교재: 전자기학, 7판, 김강욱, 김남, ...(Ulaby원저)

On the Web Caltech Physics Applets (http://hyperphysics.phy-astr.gsu.edu) Hyperphysics at Georgia Tech (http://hyperphysics.phy-astr.gsu.edu) Physics 2000 (UC Boulder) http://www.colorado.edu/physics/2000/index.pl http://www.falstad.com/mathphysics.html http://www.magnet.fsu.edu/education/tutorials/webresources.html

Do not forget Wikipedia How Stuff Works (http://www.wikipedia.org) Caltech Physics Applets (http://hyperphysics.phy-astr.gsu.edu) Hyperphysics at Georgia Tech (http://hyperphysics.phy-astr.gsu.edu) Wikipedia (http://www.wikipedia.org) How Stuff Works (http://www.howstuffworks.com)

Ch1-Overview

Maths Calculus Trig Geometry Integration by change of variables Derivatives, Chain Rule Simple PDEs Trig sin2q, sin(A+B), cosA + cosB, sin2q + cos2q Geometry Area? Perimeter? Area? Volume? Area? Volume?

Six things to do before exams Read day-to-day summaries for qualitative overview 2. Listen to lecture slide recordings 3. List important equations to remember 4. List important math formulae (calculus, trig) 5. Go over Mock Exam and solutions 6. Go over HWs and solutions Make sure you can do these (& similar!) problems ON YOUR OWN !! DO NOT LEAVE FOR THE LAST MOMENT!!

formula (포'뮬러) formulas, formulae (포'뮬리) stimulus stimuli (스티'뮬라이)

Six keys to success Be regular 2. Try to understand, not memorize 3. Challenge yourself with the concepts 4. Brush up on maths (this is often the killer!) 5. Avoid careless mistakes at exam (CHECK!) 6. Revise

Why Electromagnetism? Optics Rainbows Polaroids Lightning Northern Lights Telescope Laser Optics

Why Electromagnetism? Electronic Gadgets

Why Electromagnetism? Chemistry and Biology Chemical Reactions Neural Impulses Ion Channels Biological Processes Chemistry and Biology

Topics to Discuss History of Electromagnetics Overview of the class New trends

How do EM Fields Propagate? Transmission line equations Characteristic impedance of a line How much is reflected at a load? How would one eliminate this reflection? What about transient pulses? Transmission Line LOAD

How do static charges interact? (Electrostatics) F2 F1 r Coulomb’s Law Force  q1q2/r2 q2 q1 Gauss’s Law Flux  q1 + q2 + .. + Interaction in materials (Polarization)

Vector Fields (A “disturbance in the force”) q E = lim F/q q  0

Vector Fields (A disturbance in the force) Non-negligible q

How do magnetic fields interact? (Magnetostatics) Biot-Savart’s Law Current  magnetic field H ~ I/r dl1 I1 I2 dl2 R i12 i21 Another current senses it Force ~ i2 x H

Time variation couples E and H Ampere’s Law Varying E produces H Faraday’s Law Varying H produces E

Electrodynamics Maxwell’s Eqns. E H Varying E produces H produces E produces H .. E H Coulomb/Gauss’ Law Gauss’ law for magnets Ampere’s Law Faraday’s Law Maxwell’s Eqns.

Electrodynamics Don’t worry about memorizing these yet – We will come back to these later. But meanwhile, let’s try to understand them qualitatively.... Coulomb/Gauss’ Law Gauss’ law for magnets Ampere’s Law Faraday’s Law

Deciphering Maxwell’s equations Electric fields diverge but don’t curl Magnetic fields curl but don’t diverge

Deciphering Maxwell’s equations Electric fields diverge but don’t curl (they start and end on charges or ‘poles’) Magnetic fields curl but don’t diverge (they loop on themselves since there are no magnetic poles)

We thus have Maxwell’s equations in their simplest form (for static sources, in vacuum) Div(E)  Q Curl(E) = 0 Curl(H)  I Div(H) = 0 We will define Div and Curl precisely later on. For now, think of them as the number of diverging and curling lines respectively

We thus have Maxwell’s equations in their simplest form (for static sources, in vacuum) Div(E)  Q Curl(E) = 0 Curl(H)  I Div(H) = 0 Note how E and H equations are independent of each other !! This is true for static sources For dynamic sources (time-dependent currents), you also get dH/dt terms for the E equations and dE/dt terms for the H equations, which couple them. Varying E produces H produces E produces H .. E H

Consequences of Maxwell’s equations Waves Radiation

Wave optics l > d Interference Diffraction Polarization

Geometrical Optics l << d Mirrors Lenses

For the aspiring scientists/ engineers What lies beyond Maxwell (1873)? Will this be in your exams? NO

Nanoparticle optics Visible light = 380-620nm

“Anomalous Optics” Negative refraction: 정상적인 물질의 경우와 반대방향을 굴절 Laws are reversed ! Applications: Reverse Doppler, perfect lens

Quantum optics: Photonic Bandgap Materials = periodic structure (period = half wavelength): total reflection at resonance, total transmission off ressonance

Cellphone interactions with head

Coherent optics – Lasers coherence = same frequency and constant phase difference; produces stationary interference Atomic Laser

Maxwell’s equations hold for all systems, from large objects to nanoscale… Solar Discharge (~1.4 x 109 m dia) Molecular fields (~10-8 m dia)

…. From ultrafast to ultraslow Optical Molasses/Condensates Slow light down from 1.02 billion km/hr to 1.6 km/hr !! (Lene Hau, Harvard physicist) Cerenkov Radiation (when a particle outruns its field) Optical equivalent of a sonic boom

Even in Sci-Fi !