PH 202

Electromagnetics

3-1-0-8

 

Syllabus:

Electrostatics: Green function, Dirichlet and Neumann boundary conditions, Green function for the sphere. Laplace Equation: Separation of variables in spherical and cylindrical coordinates and general solution (Legendre polynomials, Spherical harmonics, Bessel function, etc.). Multipole expansion.

Dielectrics: Boundary value problem, Clausius-Mossotti equation. Electrostatic energy. Anisotropy and susceptibility tensor.

Magnetism: Green function method for vector potential, Magnetic materials, Boundary value problems. Magenetic field in conductors.

Maxwell equations: Time varying fields, conservation laws, Plane waves, propagation in nonconducting and conducting media. Reflection and refraction, Fresnel relations. Kramers-Kronig relations. Gauge transformation and gauge conditions. Green function method for wave equation. Retarded potentials. Poynting theorem – for harmonic fields – in dispersive medium. Transformation properties of the EM field.

Wave guides & Cavities: Fields within a conductor. Rectangular and cylindrical geometries. Orthonormal modes. Energy flow and attenuation. Power loss and Q-value. Schumann resonances.

Radiation: Oscillating source. Electric dipole, magnetic dipole, and electric quadrupole fields. Centre-fed linear antenna. Multipole expansion and multipole radiation.

Scattering: Scattering of electromagnetic waves.

Texts:

  1. David Griffiths, Introduction to Electrodynamics, 4th Ed, Cambridge University Press, 2017
  2. J. D. Jackson, Classical Electrodynamics, 3rd Ed., John Wiley, 2005.

References:

  1. E. C. Jordan and K. G. Balmain, Electromagnetic Waves and Radiating Systems, 2nd Ed., Prentice Hall of India, 1995.

  2. J. D. Kraus, Antennas, 2nd Ed., McGraw-Hill, 1988.