IB Physics SL and HL: Syllabus, Papers, IA and Revision (2025 Guide)
IB Physics changed a lot with the new guide first assessed in May 2025. The old core-plus-options structure has gone, Paper 3 has gone, and the internal assessment now allows some collaboration. Many revision notes, websites and older textbooks still describe the previous course, so students and parents often plan around a syllabus that no longer exists.
This guide explains the current IB Diploma Physics course as the IB describes it: the five themes and their topics, what is SL and what is HL, the two exam papers and their weightings, the scientific investigation (the IA), the collaborative sciences project and the Extended Essay in physics. It then covers how to choose between SL and HL, common mistakes, using the data booklet, a revision plan and how to pick an IA topic without crossing the academic-honesty line.
The IB Physics course at a glance
The IB recommends 150 teaching hours for an SL subject and 240 hours for HL. In physics, those hours are split between syllabus content and an experimental programme.
| Component | SL hours | HL hours |
|---|---|---|
| Syllabus content | 110 | 180 |
| Practical work | 20 | 40 |
| Collaborative sciences project | 10 | 10 |
| Scientific investigation (IA) | 10 | 10 |
| Total | 150 | 240 |
The course is built around three concepts that run through every theme: forces, energy and particles. Alongside the content, students must develop skills in the study of physics, grouped as tools (experimental techniques, technology and mathematics) and the inquiry process (exploring and designing, collecting and processing data, concluding and evaluating). The nature of science runs through the whole course as an overarching theme.
The five themes and their topics
The syllabus is grouped into five themes, labelled A to E. Some topics are for all students, some have extra content for HL, and some are HL only.
| Theme | Topics | SL / HL hours |
|---|---|---|
| A. Space, time and motion | A.1 Kinematics; A.2 Forces and momentum; A.3 Work, energy and power; A.4 Rigid body mechanics (HL only); A.5 Galilean and special relativity (HL only) | 27 / 42 |
| B. The particulate nature of matter | B.1 Thermal energy transfers; B.2 Greenhouse effect; B.3 Gas laws; B.4 Thermodynamics (HL only); B.5 Current and circuits | 24 / 32 |
| C. Wave behaviour | C.1 Simple harmonic motion (extra HL content); C.2 Wave model; C.3 Wave phenomena (extra HL content); C.4 Standing waves and resonance; C.5 Doppler effect (extra HL content) | 17 / 29 |
| D. Fields | D.1 Gravitational fields (extra HL content); D.2 Electric and magnetic fields (extra HL content); D.3 Motion in electromagnetic fields; D.4 Induction (HL only) | 19 / 38 |
| E. Nuclear and quantum physics | E.1 Structure of the atom (extra HL content); E.2 Quantum physics (HL only); E.3 Radioactive decay (extra HL content); E.4 Fission; E.5 Fusion and stars | 23 / 39 |
If you are working from an older book, note what has gone. The previous course had a core, additional HL topics and one option chosen from relativity, engineering physics, imaging and astrophysics. The options have been removed, and some of their content has been folded into the main syllabus at SL or HL. Anything labelled "Option A–D" or "Paper 3" belongs to the old course.
How IB Physics is assessed
All students now sit two external exam papers. Together they make up 80% of the final grade, and the scientific investigation makes up the other 20%. The weightings are the same at SL and HL; HL papers are longer and cover the HL content.
| Component | Format | SL time | HL time | Weighting |
|---|---|---|---|---|
| Paper 1 | Paper 1A: multiple-choice questions. Paper 1B: data-based questions | 1.5 hours | 2 hours | 36% |
| Paper 2 | Short-answer and extended-response questions | 1.5 hours | 2.5 hours | 44% |
| Scientific investigation (IA) | Written report, maximum 3,000 words | 10 hours | 10 hours | 20% |
Paper 1 (1A and 1B)
Paper 1A is multiple choice. Paper 1B contains data-based questions, which the IB uses to test skills such as graphing, units and uncertainties. In the IB's specimen papers, Paper 1A is out of 25 marks at SL and 40 at HL, and Paper 1B is out of 20 at both levels. The specimen papers also state that a calculator and a clean copy of the physics data booklet are required. Students who learnt the old course sometimes assume multiple choice is a no-calculator paper; for the new course, check the instructions on the current papers your school gives you.
Paper 2
Paper 2 starts with short-response questions, each focused on a narrow area of the syllabus. It ends with extended-response questions that draw on different areas of the guide and use one of the three concepts (forces, energy, particles) throughout: one such question at SL and two at HL. These are the questions that reward students who can link topics, not just recall them.
The internal assessment: the scientific investigation
The IA is an open-ended investigation in which the student gathers and analyses data to answer a research question they have formulated themselves. It is written up as a report of no more than 3,000 words, is allocated 10 hours in the recommended teaching time, and is worth 20% of the final grade at both SL and HL.
Two changes matter most:
- Limited collaboration is allowed. Students can work in small groups and share similar methods, as long as the independent or dependent variable differs between students and each student's data is their own. Every student still submits an individual report.
- Half the marks are for thinking about results. The IB states that 50% of the IA marks are allocated to the conclusion and evaluation. A tidy method with little analysis of what the data means, or of the investigation's weaknesses, will not score well.
Your teacher will share the full marking criteria for the IA; read them before you choose a topic, not after you have collected data.
Picking an IA topic
- Choose something you can measure well. Strong topics have a clear independent variable you can change over a good range and a dependent variable you can measure with sensible uncertainty, using equipment your school lab actually has or a reliable simulation or database.
- Link it to physics you can explain. A good IA tests or explores a relationship you can model, such as how damping affects an oscillation or how a resistance changes with temperature. A topic with no clear theory makes the conclusion hard to write.
- Keep the question narrow. "How does the length of a pendulum affect its period?" is manageable; "What affects pendulums?" is not.
- Plan for enough data. Aim for enough values of the independent variable, with repeats, to draw a proper graph with uncertainties.
- Think about the evaluation early. Note the problems and limitations while you work, since evaluation carries so many marks.
The academic-honesty line
The IA must be your own work. A teacher or tutor can explain the physics, suggest reading, ask questions that sharpen your research question, teach you how to propagate uncertainties or draw a best-fit line, and point out what the criteria reward. They should not choose your topic for you, design your method, collect or process your data, or write or rewrite any part of your report. The same applies to AI tools: follow your school's academic integrity policy, including what it says about AI, and cite every source you use. If you share a method with classmates, make sure your variable and your data are genuinely your own.
The collaborative sciences project
The collaborative sciences project is an interdisciplinary project that addresses a real-world problem which can be explored through the different sciences. Students work with those taking other DP science subjects, either in their own school or with other IB World Schools, and the IB recommends 10 hours for it at both SL and HL. It does not appear in the IB's assessment weightings for physics, but it is part of the course, and it builds teamwork and communication skills.
The Extended Essay in physics
The Extended Essay (EE) is a compulsory part of the Diploma core: an independent research essay of up to 4,000 words, written under the guidance of a supervisor. The IB has launched a new EE, first assessed in May 2027, with two pathways: a subject-focused essay (for example, in physics alone) or an interdisciplinary essay that combines two DP subjects.
Under the new model, students have three formal reflection sessions with their supervisor, the last being a short viva voce, and write a 500-word reflective statement. The essay is assessed on framework for the essay (6 marks), knowledge and understanding (6), analysis and line of argument (6), discussion and evaluation (8) and reflection (4). Together with Theory of Knowledge, the EE can earn up to three points towards the diploma.
A physics EE needs a focused research question that can be answered with experimental data, secondary data or simulation within the word limit. It should go beyond an IA: more depth, more reading and a sustained argument. Do not reuse your IA as your EE; check your school's rules on overlap with your supervisor.
SL or HL: how to choose
HL covers 180 hours of content compared with 110 at SL, with HL-only topics such as rigid body mechanics, relativity, thermodynamics, induction and quantum physics, plus extra depth in waves, fields and atomic physics. The papers are longer, and Paper 2 has two extended-response questions rather than one.
- Take HL if your child enjoys physics, is comfortable with algebra, graphs and trigonometry, and is heading towards engineering, physics or related university courses. Check the entry requirements of the universities and courses they are considering, including whether they ask for HL Physics.
- SL can be right if physics is a supporting subject, their other HL choices are heavy, or maths is not their strength.
- Think about maths too. Physics HL leans heavily on mathematical skills. Our guide to IB Maths AA and AI at SL and HL helps with that side of the choice.
Talk to the school's physics teacher before the deadline for changing levels. A realistic look at Grade 10 or IGCSE physics and maths results is usually a good guide.
Common mistakes in IB Physics
- Revising from the old syllabus. Past papers from before 2025 still help with physics skills, but they include option questions and a different paper structure. Match every resource against the current themes.
- Ignoring uncertainties. Uncertainties, significant figures and error bars appear in Paper 1B, Paper 2 and the IA. Many students lose marks here.
- Weak graphs. Missing units, poor scales and unjustified best-fit lines cost marks in data questions.
- Formula hunting. Picking an equation from the data booklet without understanding when it applies leads to wrong answers that look right.
- Vague explanations. In "explain" and "outline" questions, examiners want physics reasoning in clear steps, not general statements.
- Leaving the IA late. Rushed data collection makes a good conclusion and evaluation impossible, and those carry half the IA marks.
- Treating the extended-response questions as ordinary long answers. They join ideas from different themes, so practise linking topics.
Using the data booklet well
The physics data booklet is required in the exams, so learn to use it long before May.
- Use it from the first week of the course, not only for revision, so you know where each equation and constant sits.
- For each equation, know what every symbol means and the units involved. The booklet gives the equation, not the conditions for using it.
- Know which results are not in the booklet and must be understood or derived, and practise those separately.
- Always practise past and specimen questions with a clean copy of the booklet, exactly as in the exam.
A revision plan for IB Physics
| When | Focus |
|---|---|
| DP1, through the year | Keep a summary sheet for each topic as it is taught. Practise uncertainties and graphing early. Do end-of-topic questions with the data booklet. |
| End of DP1 and summer | Revise all DP1 topics. Settle the IA topic and research question with your teacher. Start reading around a possible EE question if physics is your EE subject. |
| DP2, first term | Complete the IA to your school's internal deadlines. Keep up with new topics, especially HL-only content. |
| Mock exams | Sit full Paper 1 and Paper 2 under timed conditions. Mark with markschemes and list weak topics by theme. |
| After mocks to the final exams | Work theme by theme on weak areas. Mix Paper 1A practice for speed, Paper 1B for data skills and Paper 2 extended-response questions for linking ideas. |
| Final two weeks | Full timed papers every few days, review of your mistakes list, and the data booklet at your side for every practice session. |
Use the IB's specimen papers and papers from 2025 onwards as your main exam practice, since they follow the current structure. Older papers can still be useful for topic practice if you skip questions on content that is no longer in the course.
IB Physics support in Gurgaon
In Gurgaon (Gurugram), families at the international schools along Golf Course Road, Golf Course Extension Road and Sohna Road often look for help once the HL content and IA deadlines arrive together in DP2. IB tutors who know the new guide well are fewer than CBSE tutors in any one area, so many families combine home classes in sectors such as DLF Phase 5 and Sector 54 with online sessions around mock exams. Our IB Physics tutors in Gurgaon page lists local options, and the IB and IGCSE tutoring guide for Gurgaon parents covers how to judge an international-board tutor. If you are unsure whether home or online classes suit your child, read home tutor or online tutor.
How NXTutors can help
NXTutors arranges home tutoring across Gurugram and online tutoring across India. Tell us whether your child takes Physics SL or HL, where they are in the course and what they need, whether that is new topics, exam practice or understanding the IA criteria, and we shortlist two or three tutors. You see each tutor's fee before the demo, the first class is a free demo, and switching tutor later is free. Across NXTutors, most home-tuition sessions fall between ₹800 and ₹2,500 an hour; Classes 11–12, IB/IGCSE and JEE/NEET sit toward the upper end; specialists for IB HL or JEE Advanced can charge more.
Browse IB Physics tutors or see all local options on our Gurugram tutors page.
Frequently asked questions
Is there still a Paper 3 in IB Physics?
No, IB Physics no longer has a Paper 3: since the new course was first assessed in 2025, all students sit only Paper 1 and Paper 2. Paper 1 combines 1A multiple-choice and 1B data-based questions. The option topics that used to be examined in Paper 3 have been removed, with some of their content moved into the main syllabus.
How much is the IB Physics IA worth?
The IB Physics IA, the scientific investigation, is worth 20% of the final grade at both SL and HL. It is a written report of up to 3,000 words with 10 recommended hours, and the IB allocates half of its marks to the conclusion and evaluation, so analysing results and weaknesses matters as much as a tidy method.
Can students work together on the IB Physics IA?
Yes, IB Physics students can collaborate on the IA in small groups and share similar methods, within limits the IB sets. Each student's independent or dependent variable must differ, the data must be their own, and every student submits an individual report. Follow the school's academic integrity policy before sharing a method with classmates.
What is the difference between SL and HL Physics in the IB?
IB Physics HL has 180 hours of syllabus content against 110 at SL, including HL-only topics such as rigid body mechanics, relativity, thermodynamics, induction and quantum physics. HL papers are longer, and HL Paper 2 has two extended-response questions rather than one. The weightings of the papers and the IA are the same at both levels.
Can a tutor help with the IB Physics IA without breaking the rules?
Yes, a tutor can help with the IB Physics IA by teaching rather than doing: explaining the physics and the criteria, and skills such as uncertainty analysis and graphing. The topic, method, data and writing must be the student's own. A tutor should not choose the topic, design the method, process the data or rewrite any part of the report.
How are the IB Physics exam papers weighted?
In IB Physics, Paper 1 carries 36% of the final grade, Paper 2 carries 44% and the scientific investigation 20%, at both SL and HL. Paper 1 takes 1.5 hours at SL and 2 hours at HL, and Paper 2 takes 1.5 hours at SL and 2.5 hours at HL. The specimen papers require a calculator and a clean data booklet.
Are IB Physics past papers from before 2025 still useful?
IB Physics past papers from before 2025 still help with physics skills, but they include option questions and a different paper structure. Use the IB's specimen papers and papers from 2025 onwards as the main exam practice, since they follow the current structure, and skip older questions on content that is no longer in the course.
How does the new Extended Essay work for a physics student?
The new IB Extended Essay, first assessed in May 2027, lets a physics student write a subject-focused essay or an interdisciplinary essay combining two DP subjects. Either way, the limit is 4,000 words. Students have three formal reflection sessions with their supervisor, the last a short viva voce, and write a 500-word reflective statement. Do not reuse the IA as the EE.
