Physics / core
Electromagnetism and radiation
Connect Maxwell's equations, boundary conditions, radiation, material response, and gauge-invariant electromagnetic observables.
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Module 01 core
Electromagnetism and radiation
Connect Maxwell's equations, boundary conditions, radiation, material response, and gauge-invariant electromagnetic observables.
- 01
Electrostatic potentials and boundary conditions
Solve a field problem by specifying its charges and boundaries, and understand why a valid solution is unique.
32 min - 02
Gauss's law and multipole expansion
Separate exact flux constraints from symmetry arguments and estimate distant fields with controlled multipole approximations.
34 min - 03
Magnetostatics and vector potential
Connect steady currents, magnetic circulation, flux, and the nonuniqueness of a vector potential.
34 min - 04
Maxwell equations and local conservation
Explain displacement current and track charge and energy through a finite region without losing their boundary fluxes.
35 min - 05
Electromagnetic waves and polarization
Build a transverse plane wave, distinguish its polarization from propagation, and calculate its time-averaged intensity.
34 min - 06
Interfaces and Fresnel coefficients
Derive reflected and transmitted amplitudes from boundary conditions and distinguish amplitude ratios from power fractions.
36 min - 07
Waveguides and cavity modes
Use conductor boundary conditions to select modes, calculate cutoff, and separate phase velocity from energy transport.
38 min - 08
Retarded potentials and radiation
Use causal source times, distinguish near fields from radiation, and estimate the power emitted by a small oscillating dipole.
39 min - 09
Dispersion and causal response
Connect a material's frequency-dependent polarization to delayed response, absorption, and the limits of pulse-velocity language.
40 min - 10
Gauge invariance and electromagnetic stress
Keep observable fields invariant under potential changes and calculate mechanical momentum transfer from electromagnetic stress.
39 min