Unit 4: Revolutions in Modern Physics — Lesson Planner
Unit overview
Notional time: 55 hours (including assessment)
Students examine observations that could not be explained by classical physics, leading to special relativity, quantum theory, and the Standard Model of particle physics.
Topic 1: Special relativity (16 hours)
Module 9 — Time and motion
| Lesson |
Time |
Focus |
Subject matter |
| 9.1 |
60 min |
Theory |
Einstein's postulates of special relativity. Frames of reference. Inertial and non-inertial frames. |
| 9.2 |
60 min |
Theory |
Time dilation: \(t = \frac{t_0}{\sqrt{1 - v^2/c^2}}\). Proper time vs relativistic time. |
| 9.3 |
60 min |
Theory |
Solve time dilation problems. Experimental evidence (muon decay). |
Module 10 — Length, momentum and energy
| Lesson |
Time |
Focus |
Subject matter |
| 10.1 |
60 min |
Theory |
Length contraction: \(l = l_0\sqrt{1 - v^2/c^2}\). Proper length. |
| 10.2 |
60 min |
Theory |
Relativistic momentum: \(p = \frac{mv}{\sqrt{1 - v^2/c^2}}\). |
| 10.3 |
60 min |
Theory |
Mass–energy equivalence: \(E = mc^2\). Why no object with mass can travel at \(c\). |
| 10.4 |
60 min |
Theory |
Paradoxes: twins' paradox, ladder-in-the-barn. |
| 10.5 |
60 min |
Theory |
Problem-solving and consolidation. |
| 10.6 |
60 min |
Theory |
Review: Special relativity. |
Topic 2: Quantum theory (16 hours)
Module 11 — Quantum theory and light
| Lesson |
Time |
Focus |
Subject matter |
| 11.1 |
60 min |
Theory |
Black-body radiation. Wien's displacement law. Ultraviolet catastrophe. |
| 11.2 |
60 min |
Theory |
Planck's hypothesis. Quantisation of energy: \(E = hf\). |
| 11.3 |
60 min |
Theory |
Photoelectric effect: \(E_k = hf - \phi\). Threshold frequency. |
| 11.4 |
60 min |
Practical |
Practical: Photoelectric effect simulation (PhET or equivalent). |
| 11.5 |
60 min |
Theory |
Wave–particle duality of light. Evidence for photon model. |
Module 12 — Quantum theory and atoms
| Lesson |
Time |
Focus |
Subject matter |
| 12.1 |
60 min |
Theory |
Bohr model of the atom. Electron energy levels. |
| 12.2 |
60 min |
Theory |
Emission and absorption spectra. \(E = hf = \frac{hc}{\lambda}\). |
| 12.3 |
60 min |
Theory |
de Broglie wavelength: \(\lambda = \frac{h}{mv}\). Wave–particle duality of matter. |
| 12.4 |
60 min |
Theory |
Heisenberg uncertainty principle. |
| 12.5 |
60 min |
Theory |
Review: Quantum theory. |
Topic 3: The Standard Model (13 hours)
Module 13 — The Standard Model
| Lesson |
Time |
Focus |
Subject matter |
| 13.1 |
60 min |
Theory |
Elementary particles and antiparticles. Six quarks, six leptons. |
| 13.2 |
60 min |
Theory |
Baryons and mesons. Quark composition. |
| 13.3 |
60 min |
Theory |
Four gauge bosons. Fundamental forces: strong nuclear, weak nuclear, electromagnetic, gravitational. |
Module 14 — Particle interactions
| Lesson |
Time |
Focus |
Subject matter |
| 14.1 |
60 min |
Theory |
Lepton number and baryon number. Conservation laws in particle interactions. |
| 14.2 |
60 min |
Theory |
Feynman diagrams: electron–electron, electron–positron, neutron decay. |
| 14.3 |
60 min |
Theory |
Symmetry in particle interactions. |
| 14.4 |
60 min |
Theory |
The Standard Model and the Big Bang. |
| 14.5 |
60 min |
Theory |
Review: The Standard Model. |
Assessment (10 hours)