Physics Foundations

Refreshers for the physical principles the other books lean on.

A second shared companion, alongside Math Foundations. Short, focused chapters on the physical machinery the other books invoke — Newtonian mechanics, kinetic theory, thermodynamics, fluid mechanics, elasticity, surface tension, waves as physical objects. Each chapter is a single page: link in from anywhere, scan, return.

Chapters

Chapter 1MechanicsForce, momentum, energy, rotation, the continuum limit, and the variational view
Chapter 2Kinetic theory & equipartitionPressure from collisions, Maxwell–Boltzmann, equipartition, mean free path, transport
Chapter 3ThermodynamicsState variables, the three laws, entropy, and the thermodynamic potentials
Chapter 4Free energy and phase transitionsFree energy from total entropy, chemical potential, phase coexistence, Clausius–Clapeyron, nucleation
Chapter 5Fluid mechanicsMaterial derivative, continuity, Euler, Bernoulli, Navier–Stokes, Reynolds number, Stokes flow, boundary layers
Chapter 6Viscosity, diffusion, and transportNewtonian viscosity, Fourier and Fick, random walks, Stokes drag, the Einstein relation, transport timescales
Chapter 7Elasticity and continuum mechanicsStress, strain, elastic moduli, tension, plate and membrane mechanics
Chapter 8Intermolecular forces and the liquid stateLennard-Jones, hydrogen bonds, van der Waals, cohesive limit
Chapter 9Surface tension and capillarityYoung–Laplace, contact angle, wetting, meniscus, surface free energy
Chapter 10Waves as physical objectsPhase and group velocity, dispersion, impedance, energy density and flux
Chapter 11Electromechanics and electrochemistryElectric fields, Nernst potential, electrochemical gradients, piezoelectricity
Chapter 12Scaling and dimensionless numbersReynolds, Mach, Strouhal, ka, Weber, Capillary — when each one matters
GlossaryGlossaryTerms used in this book
Chapter HHistoryA chronological narrative
Chapter SStudySpaced-repetition review
BibliographyBibliographySources and further reading