01 / Reading Guide
Reading Guide
Citation
Moebs, W., Ling, S. J., & Sanny, J. (2016). University Physics Volume 3. OpenStax. Free official edition: https://openstax.org/details/books/university-physics-volume-3
Chapter Summary
Chapter 1: The Nature of Light
Unit 1, Optics, begins by asking what light is and how it behaves, building on Maxwell's equations from Volume 2. The chapter covers the speed of light and the index of refraction, the ray model, the law of reflection, refraction and Snell's law, total internal reflection (with fibre optics), dispersion, Huygens's principle as a bridge to wave optics, and polarization, including Malus's law and Brewster's angle.
Chapter 2: Geometric Optics and Image Formation
Using ray diagrams and the mirror and thin-lens equations, the chapter explains images formed by plane and spherical mirrors and by refraction at single surfaces and thin lenses, with attention to aberrations. It then applies these ideas to the eye and vision correction, the camera, the simple magnifier, and microscopes and telescopes.
Chapter 3: Interference
Starting from the colours of soap bubbles, the chapter presents Young's double-slit experiment and the mathematics of constructive and destructive interference, multiple-slit interference, thin-film interference with phase changes on reflection, and the Michelson interferometer.
Chapter 4: Diffraction
Single-slit diffraction and its intensity (calculated with phasors), the combined pattern of a double slit, diffraction gratings, circular apertures and the Rayleigh criterion for resolution, X-ray diffraction by crystals, and holography make up this chapter, which opens with Poisson's spot.
Chapter 5: Relativity
Unit 2, Modern Physics, opens with special relativity, motivated by the corrections needed for GPS. The chapter states Einstein's postulates and derives relativity of simultaneity, time dilation (including muon lifetimes and the twin paradox), length contraction, the Lorentz transformation with space-time diagrams and the invariant interval, relativistic velocity addition, the Doppler effect for light, and relativistic momentum and energy.
Chapter 6: Photons and Matter Waves
The chapter follows the early quantum ideas: blackbody radiation and Planck's quantum, the photoelectric effect, the Compton effect, Bohr's model of hydrogen, de Broglie's matter waves (with the electron microscope as a motivating example), and wave-particle duality.
Chapter 7: Quantum Mechanics
Wave functions and Born's probability interpretation, normalization and expectation values, the Heisenberg uncertainty principle, the Schrödinger equation, and three standard applications—the particle in a box, the quantum harmonic oscillator and tunnelling through barriers—form this introduction, which opens with a quantum-computer processor.
Chapter 8: Atomic Structure
Quantum mechanics is applied to the hydrogen atom and its quantum numbers, the orbital magnetic dipole moment and electron spin, the exclusion principle and the periodic table, atomic spectra and X-rays, and lasers.
Chapter 9: Condensed Matter Physics
The chapter extends quantum ideas to molecules and solids: ionic and covalent bonds, molecular rotational and vibrational spectra, bonding in crystals, the free-electron model of metals and the Fermi energy, band theory, semiconductors and doping, devices such as diodes and transistors, and superconductivity with Cooper pairs.
Chapter 10: Nuclear Physics
Properties of nuclei, binding energy and the mass defect, radioactive decay and dating, nuclear reactions, fission, fusion (as in the Sun), and medical applications and biological effects of radiation are covered.
Chapter 11: Particle Physics and Cosmology
The final chapter links the smallest and largest scales: the classification of elementary particles, conservation laws in particle reactions, quarks, accelerators and detectors (such as ATLAS at the LHC), the Standard Model, and cosmology from the Big Bang to the evolution of the early universe, including the cosmic microwave background, dark matter and dark energy.
Key Concepts
Chapter 1: The Nature of Light
- Snell's law: the relation between angles of incidence and refraction and the refractive indices of two media.
- Total internal reflection: complete reflection when light in a denser medium meets a boundary beyond the critical angle.
- Polarization: the orientation of light's electric field, changed by polarizing filters and by reflection.
Chapter 2: Geometric Optics and Image Formation
- Thin-lens and mirror equations: relations between object distance, image distance and focal length that, with ray tracing, locate images.
- Magnification: the ratio of image to object size, combined across lenses in microscopes and telescopes.
Chapter 3: Interference
- Constructive and destructive interference: reinforcement or cancellation depending on path difference relative to wavelength.
- Thin-film interference: colours produced by reflections from the two surfaces of a film, including phase changes on reflection.
Chapter 4: Diffraction
- Single-slit minima: dark fringes where the slit width times the sine of the angle equals a whole number of wavelengths.
- Rayleigh criterion: the smallest angular separation at which two point sources can be resolved by a circular aperture.
Chapter 5: Relativity
- Postulates of special relativity: the laws of physics and the speed of light are the same in all inertial frames.
- Time dilation and length contraction: moving clocks run slow and moving objects are shortened along their motion.
- Relativistic energy: total energy includes rest energy mc², linking mass and energy.
Chapter 6: Photons and Matter Waves
- Photon: a quantum of light with energy hf, which explains the photoelectric effect.
- De Broglie wavelength: the wavelength h/p associated with any particle of momentum p.
Chapter 7: Quantum Mechanics
- Wave function and probability: the squared magnitude of the wave function gives the probability density of finding a particle.
- Heisenberg uncertainty principle: position and momentum cannot both be known with arbitrary precision.
- Quantum tunnelling: a particle's non-zero probability of passing through a barrier higher than its energy.
Chapter 8: Atomic Structure
- Quantum numbers: n, l, m and spin, which specify an electron's state in an atom.
- Pauli exclusion principle: no two electrons in an atom share all quantum numbers, which explains the periodic table.
Chapter 9: Condensed Matter Physics
- Energy bands: allowed ranges of electron energy in solids, separated by gaps that distinguish conductors, semiconductors and insulators.
- Doping: adding impurities to a semiconductor to create n-type or p-type material.
Chapter 10: Nuclear Physics
- Binding energy: the energy equivalent of a nucleus's mass defect, which explains why fission and fusion release energy.
- Radioactive decay law: exponential decay of a sample characterised by its half-life.
Chapter 11: Particle Physics and Cosmology
- Standard Model: the theory of quarks, leptons and force-carrying bosons.
- Big Bang cosmology: the model of an expanding universe evolving from a hot, dense early state.
Critical Analysis
Strengths
- Broad modern-physics coverage in one volume. After four chapters of optics, the volume moves through relativity, early quantum physics, quantum mechanics, atoms, condensed matter, nuclei and particles to cosmology, so a single free book covers a full modern-physics semester.
- Relativity treated with care for an introductory text. Chapter 5 derives the Lorentz transformation, introduces space-time diagrams and the invariant interval, and discusses the twin paradox and experimental tests such as muon lifetimes and GPS corrections, not only formulas for time dilation.
- Quantum mechanics with real calculations. Chapter 7 normalizes wave functions, computes expectation values and solves the particle in a box and harmonic oscillator, which gives students a working start rather than a purely descriptive account.
- Familiar pedagogy across the series. Examples follow the Strategy, Solution, Significance format (about 110 examples by a count of the PDF, with 75 Check Your Understanding questions), and each chapter ends with key terms, key equations, a section summary and graded exercises.
Limitations
- Relativity in one chapter only. There are no four-vectors, no systematic use of spacetime geometry and no general relativity beyond a mention in passing; students wanting a conceptual or geometric account need a dedicated text.
- Introductory depth in quantum topics. The hydrogen atom is described through its results rather than a full solution in spherical coordinates (the text says that is left to more advanced courses), and operators, spin formalism and perturbation theory are not developed.
- Uneven pace. Chapters 9–11 survey large fields (condensed matter, nuclear physics, particle physics and cosmology) in a few dozen pages each, so coverage there is descriptive.
- Optics and modern physics bundled together. Courses focused only on modern physics will skip the first four chapters; courses on optics will find no Fourier optics or laser physics beyond Section 8.6.
Where It Fits in the Course
In the Modern Physics and Relativity list, University Physics Volume 3 is a calculus-based survey of modern physics alongside Taylor and Wheeler's Spacetime Physics. The two complement each other: this volume covers all of modern physics with one chapter on relativity, while Spacetime Physics is devoted to special relativity, built on the interval and worldlines. Students can read Chapter 5 here first and then turn to Spacetime Physics for depth. Krane's Modern Physics and Thornton, Rex and Hood's Modern Physics for Scientists and Engineers are full modern-physics textbooks and are the natural step up from Chapters 5–11 of this book.
Schutz's A First Course in General Relativity and Carroll's Spacetime and Geometry are general relativity texts; this volume provides only the special-relativity background they assume and should be read well before them.
How to Use This Book
The book is intended for the third semester of a calculus-based physics sequence, after mechanics and electromagnetism (Volumes 1 and 2 or equivalent); Chapter 7 assumes comfort with differential equations at the level of solving simple second-order equations. For a modern-physics and relativity course, read Chapter 5 first, then Chapters 6–8 as the core of quantum physics, and Chapters 9–11 as surveys according to the course's emphasis. Chapters 1–4 serve an optics unit and can be omitted in a modern-physics course, although Chapters 3–4 on interference and diffraction help with matter waves in Chapter 6.
Work the Check Your Understanding questions after each example and use the chapter's key equations to organise revision. When a topic is treated briefly—general relativity, the hydrogen-atom solution, the Standard Model—use the textbook's introduction as orientation and follow up in the fuller modern-physics texts listed for the course.
Edition and Sources
This guide is based on the free PDF of University Physics Volume 3 (original publication 2016; current PDF © 2026 Rice University, licensed CC BY-NC-SA 4.0; senior contributing authors William Moebs, Samuel J. Ling and Jeff Sanny) downloaded from the official OpenStax page, https://openstax.org/details/books/university-physics-volume-3. It draws on the preface, the full table of contents, and for all eleven chapters the chapter-opening figure and introduction, the outline of every section, and the end-of-chapter summary, with counts of examples and checks of specific topics in Chapter 5.