Learning outcomes of the course unit
to provide the second year students with the basic concepts of electromagnetism
Course contents summary
electrostatic phenomena, Coulomb law, electric field, field lines, uniform field, field of a charge distribution, Gauss law and the first Maxwell’s equation, electric potential and the third Maxwell’s equation in the static case, electric dipole, conductors, Poisson and Laplace equations, capacity, capacitors, field energy density, dielectric constant, polarization mechanisms and the polarization vector, Maxwell’s equations in a dielectric, the electric displacement vector, boundary conditions.
Steady electric current:
current intensity, current density, charge conservation, Ohm law, resistivity, Joule law, electromotive field and force, Kirchhoff’s laws.
static magnetic phenomena, magnetic effects of electric current, operative definition of the magnetic induction, the second Laplace’s formula, Lorentz’s force and applications, forces and torque on a rectangular loop in a magnetic field, the first Laplace’s formula, magnetic field of various current distributions (long straight wire, circular loop and long solenoid), the second Maxwell’s equation, Ampère’s law and the fourth Maxwell’s equation in the static case, the magnetic vector potential, forces between two parallel wires and definition of electric current unit, magnetic permeability of various materials, diamagnetism and Larmor precession, paramagnetism and ferromagnetism, the magnetization vector, magnetic susceptibility, polarization currents, magnetic force on various materials, Maxwell’s equations in matter, boundary conditions, ferromagnetic materials, magnetic circuits and Hopkinson’s law.
Time varying electric and magnetic fields:
electromagnetic induction, Faraday-Neumann law, Lenz’s law, the third Maxwell’s equation with varying fields, the displacement current and the fourth Maxwell’s equation, quasi-stationary limit, self-inductance, RL circuit, mutual inductance, magnetic energy density, dissipation in a ferromagnetic material, electrodynamic potentials, Lorentz’s gauge, the retarded potential integral.
Exercises for the solution of selected problems.
- C. Mencuccini e V. Silvestrini: Fisica II (Elettromagnetismo-Ottica). Liguori Ed.
- R. Caciuffo e S. Melone, “Fisica Generale”, Vol. 2, Masson, Milano
- R. P. Feynman, R. B. Leighton, M. Sands: The Feynman Lectures on Physics, vol 2
- Halliday, Resnick, Krane, Fisica 2, Casa Ed. Ambrosiana.
Frontal lectures and exercises (8 credits).
Tests during the course and final oral examination.