ECE 230, Winter 2020
Fields and waves
Instructor
Sayak Bhattacharya
Office hour: Mon, 56pm (B603, R&D Block)
Email: sayakatiiitd.ac.in
Lectures: Mon, Fri 2:304:00pm (Room: A007)
Tutorials: Wed 2:303:30pm ((Room: A106,B105,A006))
Teaching Assistants
Yashwant Jain
Shalin Verma
Dinesh Rano
Office hours: By appointment
Announcements
Click here to download assignment 2. Deadline is 6 p.m., April 3. Email your answer scripts to the instructor.
Click here to download assignment 1. New deadline is 6 p.m., March 21. Email your answer scripts to the instructor.
Midsemester examination (syllabus: till lect. 10) to take place on Feb. 20, 2020 (Thurs), 1011:30am @C21
Electromagnetic poster day temporarily cancelled due to COVID19. A new date 'll be announced in due time. But keep studying your topics. [Guidelines: Form a group of 4 and select a topic related to Electromagnetics in nature or Electromagnetics in industry. The topics 'll be reviewed for technical richness before you start preparing for the poster day. All 4 members of the group needs to present and answer questions. Other faculty members 'll evaluate your performances and grade you].
Fri, Jan 31, 2020: No lecture (research showcase day).
Wed, Jan 08, 2020: tutorial to be held only in A106 (for all groups).
Course webpage online! The first lecture 'll be on Fri, Jan. 3, 2020.
Lectures
S. No.  Date  Topic  Advised Reading  Lectures 
1  Jan 3  Course outline & grading policy, Introduction & historical background Review of vector calculus  Griff. ch 1, Sad. ch 1, 2, 3 Feyn. ch 1,2
 Slides
 2  Jan 6  Different coordinate systems, Line integral & conservative fields Volume, surface integral & divergence theorem Earnshaw's theorem & Paul trap  Griff. ch 1, Sad. ch 2, 3 Feyn. ch 2
 Slides
 3  Jan 10  Stoke's theorem, Dirac delta function in 3D & volume charge density of point charges How much is divergence of a radially directed inverse square function Coulomb's law and Gauss's law  Griff. ch 1, ch 2  Slides Lecture note
 4  Jan 13  Electrostatic potential, potential due to charge distribution, Equipotential surface, Demo starts at 44:00 Perfect conductors, Electric field and volume charge inside a perfect conductor, perfect conductors as equipotentials Electrostatic boundary conditions Poisson's and Laplace's eq., solving Laplace's eq.
 Griff. ch 2, for solution of Laplace's eq. Griff. ch 3  Lecture note
 5  Jan 20  Energy of an assembly of pointcharges, Electrostatic energy density, Electrostatic field inside a material Induced dipole and dipole moment of polar molecules Polarization vector, bound charges, Gauss's law in presence of a material medium Physical interpretation of bound surface and volume charge densities: are they real?
 For the first two topics: Griff. ch 2; Griff. ch 4 for the rest  Lecture note
 6  Jan 21  Surprise quiz 1 of 5
  Questions Solutions
 7  Jan 24  Lorentz force law, demo at 14:08 , Parallel and antiparallel currents, demo at 15:38 Charged particles in nonuniform magnetic fields, Greatest Electromagnetic show on the earth: Aurora Force on a currentcarrying wire, surface and volume current density More on currents: Ohm's law and eqn. of continuity Relaxation time: conductors and insulators
 Griff. ch 5  Lecture note
 8  Jan 27  BiotSavart Law,Divergence and curl of magnetic field, Ampere's law Magnetic vector potential and its nonuniqueness
 Griff. ch 5  Lecture note
 9  Feb 03  Quiz 2 of 5 Openclassnote
  Questions
 10  Feb 07  Boundary conditions for tangential and normal components of magnetic field Magnetic field in matter Magnetic dipole in a uniform magnetic field Force on a magnetic dipole in a nonuniform magnetic field: paramagnetismDemo starts at 41:00 (liquid hanging from a magnet!) Magnetization, Ampere's law for magnetized materials, magnetic susceptibilty and permeability para, dia and ferromagnetic materials
Demo starts at 21:55 (You can listen to the domains in a ferromagnetic material as they flip) Demo starts at 35:51 (Curie temperature)  Griff. ch 5 for magnetic field boundary conditions, Griff. ch 6 for the rest  Lecture note
 11  Feb 10  Review of quiz 2 A glitch in Ampere's law: Introduction to Electrodynamics
 Griff. 7.3.1 and 7.3.2 
 12  Feb 14  EMF and Faraday's law of induction
 Griff. ch 7  Lecture note
 13  Feb 28  Quick recap: Faraday's law of induction and Maxwell's modification to Ampere's law Maxwell's equations: differential form, integral form, timedomain and frequency domain Concept of complex and frequency dependent permittivity
 Griff. ch 7  Lecture note
 14  Mar 2  EM wave propagation: a physical picture, Polarization of EM waves, Displacement current High frequency behavior of circuits: introduction to transmission line Working mechanism of a transmitting antenna: Demo 1, Demo 2 Working mechanism of a receiving antenna: Demo Potentials in Electrodynamics, Gauge freedom, Coulomb gauge and Lorentz gauge  Griff. ch 10.1  Lecture note
 15  Mar 6  Dispersive medium: origin and frequency dependence of dielectric constant Scalar wave equation Electromagnetic wave equation, Helmholtz equation
 Griff. ch 9 (Electromagnetic Waves)  Lecture note
 16   Electromagnetic wave equation in 1D: uniform plane wave Electromagnetic wave equation in 3D
 Griff. ch 9 (Electromagnetic Waves)  Lecture note, Video
 17   Poynting's theorem Electromagnetic waves in materials: attenuation in conducting materials, skin depth
 Poynting's theorem: Griff. ch 8, Griff. ch 9 for the rest
 Lecture note

Practice problems
Set 1 (covers till lecture 8)
Tutorials
Tutorial 1
Tutorial 2
Tutorial 3 and 4
Tutorial 5
Tutorial 6
Tutorial 8
References
David J. Griffiths, Introduction to Electrodynamics, Pearson 4th Ed. (2015).
R. Feynman, R. Leighton, M. Sands, The Feynman Lectures on Physics (Vol II)
Matthew. N. O. Sadiku, Elements of Electromagnetics.
