Question 1
A box of mass m rests without moving on a rough slope at angle θ to the horizontal. The coefficient of static friction is μₛ. What is the size of the frictional force on the box?
The physics syllabus: SL and HL, theme by theme
Five themes and 24 topics. Five topics are for HL students only and seven more go further at HL; HL has 180 hours of syllabus content against 110 at SL.
26 weeks at SL, 104 hours in all
Start with Theme A
Space, time and motion: 23.6 of your hours. It is 27 of the 110 hours of SL syllabus content, 25%.
| Theme | Your hours | Share of the syllabus |
|---|---|---|
| Theme A: Space, time and motion | 23.6 | 25% |
| Theme B: The particulate nature of matter | 20.9 | 22% |
| Theme E: Nuclear and quantum physics | 20.1 | 21% |
| Theme D: Fields | 16.6 | 17% |
| Theme C: Wave behaviour | 14.8 | 15% |
Week by week
- Week 1Theme A: Space, time and motion
- Week 2Theme A: Space, time and motion
- Week 3Theme A: Space, time and motion
- Week 4Theme A: Space, time and motion
- Week 5Theme A: Space, time and motion
- Week 6Theme A: Space, time and motion, Theme B: The particulate nature of matter
- Week 7Theme B: The particulate nature of matter
- Week 8Theme B: The particulate nature of matter
- Week 9Theme B: The particulate nature of matter
- Week 10Theme B: The particulate nature of matter
- Week 11Theme B: The particulate nature of matter
- Week 12Theme B: The particulate nature of matter, Theme E: Nuclear and quantum physics
- Week 13Theme E: Nuclear and quantum physics
- Week 14Theme E: Nuclear and quantum physics
- Week 15Theme E: Nuclear and quantum physics
- Week 16Theme E: Nuclear and quantum physics
- Week 17Theme E: Nuclear and quantum physics, Theme D: Fields
- Week 18Theme D: Fields
- Week 19Theme D: Fields
- Week 20Theme D: Fields
- Week 21Theme D: Fields, Theme C: Wave behaviour
- Week 22Theme C: Wave behaviour
- Week 23Theme C: Wave behaviour
- Week 24Theme C: Wave behaviour
- Week 25Timed SL Paper 1 practice, then review every miss
- Week 26Timed SL Paper 1 practice, then review every miss
| Paper 1 | Paper 1A multiple choice and Paper 1B data-based questions: 1.5 hours at SL, 2 hours at HL, 36% |
|---|---|
| Paper 2 | Short-answer and extended-response questions: 1.5 hours at SL, 2.5 hours at HL, 44% |
| Scientific investigation | Your own investigation, a report of at most 3,000 words: 20% |
| Teaching hours | 150 at SL and 240 at HL, as for every Diploma subject |
The five themes
- A Space, time and motion: kinematics; forces and momentum; work, energy and power; rigid body mechanics (HL); Galilean and special relativity (HL). 27 hours at SL, 42 at HL.
- B The particulate nature of matter: thermal energy transfers; the greenhouse effect; gas laws; thermodynamics (HL); current and circuits. 24 hours at SL, 32 at HL.
- C Wave behaviour: simple harmonic motion; the wave model; wave phenomena; standing waves and resonance; the Doppler effect. 17 hours at SL, 29 at HL.
- D Fields: gravitational fields; electric and magnetic fields; motion in electromagnetic fields; induction (HL). 19 hours at SL, 38 at HL.
- E Nuclear and quantum physics: the structure of the atom; quantum physics (HL); radioactive decay; fission; fusion and stars. 23 hours at SL, 39 at HL.
What HL adds
Five topics are taught only at HL: rigid body mechanics, Galilean and special relativity, thermodynamics, induction and quantum physics. Seven topics are taught to everyone with extra content at HL: simple harmonic motion, wave phenomena, the Doppler effect, gravitational fields, electric and magnetic fields, the structure of the atom and radioactive decay.
Fields gains the most: 38 hours at HL against 19 at SL. Every theme is examined on both papers at both levels.
The practical side
The experimental programme is 40 hours at SL and 60 at HL: practical work, the collaborative sciences project (10 hours) and the scientific investigation (10 hours). Three concepts run through every theme: forces, energy and particles.
Plan your hours by theme
The planner above splits your revision across the five themes by their teaching hours at your level and how sure you feel of each, then lays it out week by week, keeping the last weeks for timed Paper 1 practice.
Try 2 questions
Question 2
The graph shows how the gravitational field strength g outside a planet of radius R varies with the distance r from its centre, from r = R to r = 2R. What is g at r = 4R?
Next step
The IB's Diploma Programme physics page, with the subject brief
Questions people ask
What is the difference between IB Physics SL and HL?
HL covers 180 hours of syllabus content against 110 at SL: five extra topics (rigid body mechanics, relativity, thermodynamics, induction and quantum physics) and more depth in seven others. HL papers are longer: Paper 1 is 2 hours against 1.5, and Paper 2 is 2.5 hours against 1.5.
How many themes are in IB Physics?
Five: A Space, time and motion; B The particulate nature of matter; C Wave behaviour; D Fields; E Nuclear and quantum physics, with 24 topics between them.
When was the current physics syllabus first examined?
In 2025. The IB lists its first teaching as August or September 2023.
Are there options in IB Physics?
The current course is the five themes for every student, with the HL topics added at HL.