Electromagnetism
The unified physics of electricity and magnetism — from the force between two charges to the waves that carry light across the universe. Formalised by James Clerk Maxwell in 1865, building on a century of experimental work by Coulomb, Faraday, Ampère, and others.
Electromagnetism is the branch of physics describing the interaction of electrically charged particles via electric and magnetic fields, unified by Maxwell's equations into a single field theory that also predicts and explains the existence of light as a self-propagating electromagnetic wave.
What this domain covers
Electromagnetism spans electrostatics (forces and fields from stationary charges), magnetostatics (forces and fields from steady currents), electromagnetic induction (how changing magnetic fields generate electric fields, and vice versa), Maxwell's unifying field equations and the electromagnetic waves they predict, electric circuits (the practical, everyday application of these laws), and the wave-optics behaviour of light as an electromagnetic phenomenon.
Electrostatics
- Electric Charge [DONE — Session 07 — 2026-07-08]
- Coulomb's Law [DONE — Session 07 — 2026-07-08]
- Electric Field [DONE — Session 07 — 2026-07-08]
- Electric Flux [PENDING FULL ENTRY]
- Gauss's Law [DONE — Session 07 — 2026-07-08] · equation page
- Electric Potential [DONE — Session 07 — 2026-07-08]
- Capacitance [DONE — Session 07 — 2026-07-08]
- Dielectrics [PENDING FULL ENTRY]
- Electric Dipole [PENDING FULL ENTRY]
Magnetostatics
- Magnetic Field [DONE — Session 08 — 2026-07-08] · simulation
- Magnetic Force [DONE — Session 08 — 2026-07-08]
- Biot-Savart Law [DONE — Session 08 — 2026-07-08]
- Ampère's Law [PENDING FULL ENTRY]
- Magnetic Dipole [PENDING FULL ENTRY]
- Magnetic Flux [PENDING FULL ENTRY]
- Magnetic Materials [PENDING FULL ENTRY]
Electromagnetic Induction
- Faraday's Law [DONE — Session 08 — 2026-07-08]
- Lenz's Law [PENDING FULL ENTRY]
- Inductance [PENDING FULL ENTRY]
- Mutual Inductance [PENDING FULL ENTRY]
- Self-Inductance [PENDING FULL ENTRY]
- Transformers [PENDING FULL ENTRY]
Maxwell's Equations
- Maxwell's Equations (Equation Page) [DONE — Session 03 — 2026-07-05]
- Displacement Current [PENDING FULL ENTRY]
- Electromagnetic Waves [PENDING FULL ENTRY]
- Poynting Vector [PENDING FULL ENTRY]
- Electromagnetic Spectrum [PENDING FULL ENTRY]
- Speed of Light [PENDING FULL ENTRY]
Circuits
- Ohm's Law [DONE — Session 08 — 2026-07-08]
- Resistance [PENDING FULL ENTRY]
- Kirchhoff's Laws [PENDING FULL ENTRY]
- AC Circuits [PENDING FULL ENTRY]
- Impedance [PENDING FULL ENTRY]
- Resonant Circuits [PENDING FULL ENTRY]
- RC Circuits [PENDING FULL ENTRY — simulation available: try it]
- RL Circuits [PENDING FULL ENTRY]
Optics (Electromagnetic)
- Geometric Optics [PENDING FULL ENTRY]
- Reflection [PENDING FULL ENTRY]
- Refraction [PENDING FULL ENTRY]
- Snell's Law [PENDING FULL ENTRY]
- Total Internal Reflection [PENDING FULL ENTRY]
- Polarisation [PENDING FULL ENTRY]
- Wave Optics [PENDING FULL ENTRY]
- Interference [PENDING FULL ENTRY]
- Diffraction [PENDING FULL ENTRY]
Sources
- Griffiths, D.J. (2017). Introduction to Electrodynamics, 4th ed. Cambridge University Press.
- Maxwell, J.C. (1873). A Treatise on Electricity and Magnetism. Oxford: Clarendon Press. Public domain.
- Feynman, R.P. et al. The Feynman Lectures on Physics, Vol. II. feynmanlectures.caltech.edu