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IB Physics Syllabus (HL & SL) – Complete Guide
TUTORZONE SUBJECT GUIDE · IB
IB Physics is a two-year Diploma Programme subject built around five themes — from space, time and motion to nuclear and quantum physics. This complete guide covers the 2025-onwards syllabus that students sit in the May and November 2026 examination sessions: every theme and topic, the SL and HL assessment structure with marks and weightings, the scientific investigation, and how top-scoring students prepare.
Direct Answer：What does IB Physics cover?
IB Physics covers five themes — A: Space, time and motion; B: The particulate nature of matter; C: Wave behaviour; D: Fields; and E: Nuclear and quantum physics — organised into 24 topics. Standard Level (SL) students study 150 recommended teaching hours, while Higher Level (HL) adds five HL-only topics and deeper quantitative treatment within 240 hours. Assessment is 80% external (Paper 1 and Paper 2) and 20% internal (the scientific investigation).
What Is IB Physics (HL & SL)?
IB Physics is one of the Group 4 experimental sciences in the International Baccalaureate Diploma Programme (IBDP), studied over two years by students aged 16 to 19. It can be taken at Standard Level (SL) or Higher Level (HL): the IB recommends 150 teaching hours for SL and 240 for HL. The current syllabus was introduced for first teaching in August 2023 and first assessment in May 2025, and it is the version students will sit in the May and November 2026 sessions.
The 2025 syllabus replaced the old core-plus-options structure with five compulsory themes that every IB Physics student — SL or HL — studies in full.
Two features define the new course. First, the previous menu of optional topics (relativity, engineering physics, imaging, astrophysics) is gone: all students now cover the same five themes, and the difference between SL and HL is depth rather than coverage. Second, the old Paper 3 experimental paper no longer exists — experimental skills are assessed through data-based questions in Paper 1B and through the individual scientific investigation.
Syllabus Topics — The Five Themes (A to E)
The syllabus content is organised into 24 topics across five themes. Recommended teaching hours per theme: Theme A 27 (SL) / 42 (HL); Theme B 24 / 32; Theme C 17 / 29; Theme D 19 / 38; Theme E 23 / 39. Five topics are HL only: A.4, A.5, B.4, D.4 and E.2.
Theme A — Space, Time and MotionSL 27 hours · HL 42 hours
- A.1 Kinematics — displacement, velocity, acceleration, projectile motion
- A.2 Forces and momentum — Newton’s laws, free-body diagrams, momentum and impulse, circular motion
- A.3 Work, energy and power — conservation of energy, efficiency, energy density of fuels
- A.4 Rigid body mechanics (HL only) — torque, rotational equilibrium, rotational kinematics
- A.5 Galilean and special relativity (HL only) — reference frames, time dilation, length contraction, space-time diagrams
Theme B — The Particulate Nature of MatterSL 24 hours · HL 32 hours
- B.1 Thermal energy transfers — temperature, specific heat capacity, phase changes, black-body radiation
- B.2 Greenhouse effect — molecular energy levels, the enhanced greenhouse effect
- B.3 Gas laws — the kinetic model, ideal gas law, internal energy of a monatomic gas
- B.4 Thermodynamics (HL only) — the first and second laws, entropy
- B.5 Current and circuits — electric current, resistance, emf and internal resistance, energy sources
Theme C — Wave BehaviourSL 17 hours · HL 29 hours
- C.1 Simple harmonic motion — the SHM model, energy changes in oscillations
- C.2 Wave model — wave properties, sound waves, electromagnetic waves
- C.3 Wave phenomena — reflection, refraction, diffraction, interference, standing waves
- C.4 Standing waves and resonance — natural frequency, damping, resonance
- C.5 Doppler effect — the Doppler effect for sound and light, applications
Theme D — FieldsSL 19 hours · HL 38 hours
- D.1 Gravitational fields — Kepler’s laws, Newton’s law of gravitation, gravitational field and potential
- D.2 Electric and magnetic fields — Coulomb’s law, electric fields, magnetic fields, the nature of the electron
- D.3 Motion in electromagnetic fields — charged particles in fields, force on a current-carrying conductor
- D.4 Induction (HL only) — electromagnetic induction, generators, Lenz’s law
Theme E — Nuclear and Quantum PhysicsSL 23 hours · HL 39 hours
- E.1 Structure of the atom — models of the atom, energy levels, wave-particle duality
- E.2 Quantum physics (HL only) — the photoelectric effect, matter waves, the uncertainty principle
- E.3 Radioactive decay — half-life, decay modes, radioactive dating
- E.4 Fission — chain reactions, nuclear power, management of fission products
- E.5 Fusion and stars — stellar evolution, nucleosynthesis, the evolution of the universe
Exam Format & Paper Structure
IB Physics is assessed 80% externally and 20% internally. There are only two external papers — there is no Paper 3 in the new syllabus. Paper 1 comes in two booklets (1A multiple-choice and 1B data-based) that are completed together. Calculators are permitted in every paper, each student receives a clean copy of the Physics data booklet, and no marks are deducted for incorrect multiple-choice answers.
| Component | Level | Content | Duration | Marks | Weighting |
|---|---|---|---|---|---|
| Paper 1 | SL | 1A: 25 multiple-choice questions · 1B: data-based questions | 1 hr 30 min | 45 | 36% |
| Paper 2 | SL | Short-answer and extended-response on standard level material only | 1 hr 30 min | 55 | 44% |
| Paper 1 | HL | 1A: 40 multiple-choice questions · 1B: data-based questions | 2 hours | 60 | 36% |
| Paper 2 | HL | Short-answer and extended-response on standard level and additional higher level material | 2 hr 30 min | 90 | 44% |
| Internal assessment | SL & HL | The scientific investigation — one task, ~10 hours | — | 24 | 20% |
The internal assessment (IA) is the same at SL and HL: each student designs, carries out and reports a scientific investigation of their own choice, worth 24 marks and 20% of the final grade. It is internally assessed by the teacher and externally moderated by the IB. Schools also run a collaborative sciences project (about 10 hours) that is not formally assessed. Assessment objectives:
AO1 — Knowledge and understanding
Demonstrate knowledge and understanding of facts, concepts and techniques from the syllabus.
AO2 — Application and analysis
Apply and analyse concepts, data and models to solve problems in familiar and unfamiliar situations.
AO3 — Experimental skills
Design investigations, collect and process data, and evaluate methods and results.
Why Study IB Physics?
Gatekeeper for STEM Degrees
IB Physics HL is a standard (often required) subject for engineering, physics, computer science, architecture and quantitative finance at top universities worldwide, including in the UK, US, Canada, Australia and Hong Kong.
IB-Style Thinking
The course trains problem-solving, data analysis and experimental design through the IA — the same skills that university admissions interviews and science careers reward.
Modern and Relevant Content
The 2025 syllabus weaves in current science — the enhanced greenhouse effect, energy density of fuels, stellar evolution — so students see physics in the real world around them.
Study Tips & Preparation Strategies
- Learn the data booklet——The Physics data booklet is provided in every exam; know exactly what is in it (constants, equations, uncertainty rules) so you never waste time hunting for a formula.
- Practise past papers——Use May and November past papers from 2025 onwards (the current syllabus), timed and marked against the official markschemes, and study examiner reports for the traps examiners flag.
- Master the command words——State, describe, explain, suggest, evaluate and deduce each demand a different style of answer; marks are awarded for exactly what the command asks.
- Do the experimental programme——The required practicals feed directly into Paper 1B data-based questions and the IA; keep a lab notebook of methods, variables and uncertainties.
- Build the IA early——Choose an investigation you genuinely enjoy, plan it in Term 1 of Year 2, and use the teacher’s one-draft feedback cycle properly — the IA is 20% of your grade.
- Practise with and without the calculator——Estimate answers before calculating; examiners reward sensible estimates and punish answers with no units.
Who Should Take IB Physics?
- Students aiming at university courses in engineering, physics, computer science, mathematics, architecture or quantitative finance
- Those who enjoy solving quantitative problems and want a subject that connects mathematics directly to the physical world
- Future medicine and life-science applicants who want a rigorous Group 4 science alongside Chemistry and/or Biology
- Students who can commit to sustained, regular practice — IB Physics rewards consistent work far more than last-minute cramming
Recommended Resources
- Official IB Physics guide——the Physics guide (first assessment 2025) from the IB Programme Resource Centre, plus official specimen papers and past papers.
- Physics data booklet——download a clean copy from IBIS or the Programme Resource Centre and use it in every practice session.
- K. A. Tsokos, Physics for the IB Diploma——the standard course companion, updated for the current syllabus, with hundreds of problems.
- Chris Hamper, IB Physics (Pearson Baccalaureate)——excellent for the experimental programme and IA guidance.
- Video walkthroughs——channels such as OSC and Chris Doner cover every topic in the new syllabus, including the HL-only content.
- Sibling guides——build the foundations with our IGCSE Physics Complete Guide, see how maths powers the subject in our A-Level Maths Syllabus guide, and explore the other Group 4 sciences with our IGCSE Chemistry Syllabus and IGCSE Biology Syllabus guides.
Expert Advice: How to Score a 7
Top-scoring IB Physics students do not memorise answers — they learn to think in quantities, units and orders of magnitude, and they treat every past paper as a real exam.
- Score the easy marks——MCQs carry no negative marking, so attempt every question; on Paper 2, always write the equation before substituting numbers, because method marks are awarded even when the answer is wrong.
- Units and uncertainties everywhere——Give answers with units and correct significant figures, and practise propagation of uncertainties for the IA and Paper 1B.
- Practise HL-only topics from day one——A.4 rigid body mechanics, A.5 relativity, B.4 thermodynamics, D.4 induction and E.2 quantum physics are new territory for every student; spreading them across two years beats cramming them in Year 2.
- Timed full papers——HL Paper 2 is 2.5 hours of sustained writing; build up to full timed papers from the first term of Year 2 so stamina is never the reason marks are lost.
Frequently Asked Questions (FAQ)
Q: What is the difference between IB Physics SL and HL?
HL adds five HL-only topics (A.4 Rigid body mechanics, A.5 Galilean and special relativity, B.4 Thermodynamics, D.4 Induction and E.2 Quantum physics) and treats shared topics with greater mathematical depth. The IB recommends 240 teaching hours for HL versus 150 for SL, and HL papers are longer with more marks: Paper 1 is 2 hours (60 marks) and Paper 2 is 2 hours 30 minutes (90 marks), against 1 hour 30 minutes (45 marks) and 1 hour 30 minutes (55 marks) at SL.
Q: Is there a Paper 3 in the new IB Physics syllabus?
No. The previous options papers and Paper 3 were removed in the 2025 syllabus. Experimental skills are now assessed through the data-based questions in Paper 1B and through the scientific investigation (IA), which is worth 20% of the final grade.
Q: How much is the IB Physics internal assessment worth?
The scientific investigation is worth 24 marks — 20% of the final grade at both SL and HL. Students spend about 10 hours on it, it is marked by the teacher and moderated by the IB, and it must be the student’s own work; teachers give advice on one draft only.
Q: What is the hardest topic in IB Physics?
HL students most often name A.4 rigid body mechanics and E.2 quantum physics, which demand strong algebra and abstract reasoning; at SL, D.2 electric and magnetic fields and the quantitative wave topics in Theme C are the common stumbling blocks. Starting these topics early and practising regularly is the best defence.
Further Resources & Next Steps
- Official Resources——the International Baccalaureate Organisation (IBO) publishes the Physics guide (first assessment 2025), specimen papers, past papers and the Physics data booklet on the Programme Resource Centre (IBIS); access is via your school’s IB coordinator.
- Further Reading——K. A. Tsokos’s Physics for the IB Diploma (updated for the current syllabus) and Chris Hamper’s IB Physics course companion are the two most widely used study texts.
- Parent Tips——Ask your child to explain each week’s physics to you in plain language; teaching a concept aloud is the fastest way to expose gaps, and a regular, short practice routine beats marathon weekend sessions.
Note: The information above is for reference only. Please consult professional education institutions for details.
This article was initially drafted and organised with AI. Editor / Professor Chan Kwok-wai; Managing Editor / Kong Yee-leung
Direct Answer：What topics are in the IB Physics syllabus?
The IB Physics syllabus (first assessment 2025) has 24 topics in five themes: A Space, time and motion (kinematics, forces, energy, rigid body mechanics and relativity); B The particulate nature of matter (thermal transfers, the greenhouse effect, gas laws, thermodynamics and circuits); C Wave behaviour (SHM, the wave model, wave phenomena, standing waves and the Doppler effect); D Fields (gravitational, electric and magnetic, and induction); and E Nuclear and quantum physics (the atom, quantum physics, radioactivity, fission, fusion and stars).
Direct Answer：Is IB Physics hard?
IB Physics is demanding — especially at HL, which adds five HL-only topics and requires strong algebra — but it is very achievable with a steady routine: master the data booklet, practise current-syllabus past papers from 2025 onwards under timed conditions, and treat the experimental programme and IA as exam preparation rather than an afterthought. Students who do this consistently score 6s and 7s.
