IB Physics Guide: SL vs HL, Topics, Data Booklet and IA (2026)

Short answer: IB Physics is the International Baccalaureate Diploma physics course, offered at standard level (150 teaching hours) and higher level (240 hours). The current syllabus, first assessed in 2025, has five themes. Two exam papers count for 80% of the grade and a 3,000-word scientific investigation for 20%. Students use the official data booklet in every exam.

IB Physics rewards students who understand where equations come from and can work with real data. This guide covers the syllabus, the papers, the data booklet and the internal assessment, with a worked exam-style problem.

Key points

• Two levels SL is 150 teaching hours; HL is 240 hours with extra topics and longer papers.
• Five themes Space, time and motion; matter; waves; fields; nuclear and quantum physics.
• Two papers, 80% Paper 1 is worth 36% and Paper 2 is worth 44% at both levels.
• Investigation, 20% One scientific investigation, a report of up to 3,000 words, marked out of 24.
• Data booklet in every paper Each student gets a clean copy of the official booklet in the exam.
• Graded 1 to 7 Physics contributes up to 7 of the 45 Diploma points.

What is IB Physics?

IB Physics is one of the experimental sciences in the IB Diploma Programme (DP). The IB describes it as a course that takes a mathematical approach to models, theories and laws, with an emphasis on data analysis, and that runs from the smallest particles to the distances between galaxies (IB Diploma Programme physics).

Three concepts run through every part of the course: forces, energy and particles. Practical work is built in, from guided labs to open-ended inquiry, simulations and modelling.

The current course was first taught in August 2023 and first assessed in 2025. If you are using notes or past papers from before 2025, expect older topic names (such as “circular motion and gravitation” or “energy production”) and a different paper structure. For how IB Physics fits alongside IB Math, see our overview of IB math and physics tutoring.

What is the difference between IB Physics SL and HL?

SL and HL share the same five themes, the same experimental programme and the same internal assessment. HL adds more content, some of it conceptually harder, and longer exams. The IB calls the difference one of both breadth and depth.

What extra content is in IB Physics HL?

Five subtopics are HL only: A.4 rigid body mechanics, A.5 Galilean and special relativity, B.4 thermodynamics, D.4 induction and E.2 quantum physics. HL students also study additional material within simple harmonic motion, wave phenomena, the Doppler effect, gravitational fields, electric and magnetic fields, atomic structure and radioactive decay.

In practice, HL means more calculus-style thinking about rates of change (induction, exponential decay), more field theory (potential and potential energy), and topics such as rotational dynamics and relativity that are new to most students.

Should you take Physics SL or HL?

• Choose HL if you are considering physics, engineering, astronomy or another physical science at university, or a program that lists HL Physics as a requirement. Check each university’s requirements directly.
• Choose SL if you want a strong science grounding but your main HL subjects lie elsewhere, or if you would rather spend HL hours on subjects closer to your intended major.
• Look at your math. HL Physics leans on algebra, trigonometry, logarithms and exponentials. Students taking HL Math alongside it usually find the overlap helpful.

What topics are in the IB Physics syllabus?

The syllabus is organized into five themes, each split into numbered topics (IB Physics subject brief). Topics marked HL only are not studied at SL.

Each topic in the IB guide comes with guiding questions and a list of understandings, and the HL-only material is marked as “additional higher level” content within each topic.

Tutor tip: The themes are not meant to be learned in isolation. The IB builds the course around linking questions, such as how electric fields are like gravitational fields, so practise explaining one topic using ideas from another.

How is IB Physics assessed?

Every IB Physics student sits two exam papers and completes one internally assessed scientific investigation. The weightings are the same at SL and HL.

• 36% Paper 1: multiple choice and data-based questions
• 44% Paper 2: short-answer and extended response
• 20% scientific investigation (internal assessment)
• 24 marks available for the investigation

Paper 1

Paper 1 comes in two booklets completed in one sitting. Paper 1A is multiple choice: 25 questions at SL and 40 at HL, with no marks deducted for wrong answers, so never leave one blank. Paper 1B is 20 marks of data-based questions, where you interpret graphs and experimental results.

Paper 2

Paper 2 has short-answer and extended-response questions: 50 marks in 1 hour 30 minutes at SL, and 90 marks in 2 hours 30 minutes at HL. These questions often build in parts, so an early answer feeds into later ones. Calculators are permitted on both papers.

When are the IB Physics exams?

The IB runs exam sessions in May and November; most schools use May. Your school registers you for SL or HL and the session.

What is in the IB Physics data booklet?

The Physics data booklet is the official reference of equations and constants for the course, for use in class and in the exams. Every student must have access to a clean copy during Paper 1 and Paper 2, and schools download it from the IB’s teacher resource site. The IB does not post it publicly, so ask your teacher for the current version (first assessment 2025) rather than relying on older copies online.

The booklet is organized in this order:

• Mathematical equations and how to handle uncertainties
• Fundamental constants, such as G = 6.67 × 10⁻¹¹ N m² kg⁻² and g = 9.8 m s⁻²
• Metric (SI) multipliers and unit conversions
• Electrical circuit symbols and the electromagnetic spectrum
• Equations for each theme, A to E, split into “standard level and higher level” and “additional higher level” blocks

Because HL-only equations sit in their own blocks, SL students can ignore those blocks entirely. HL students should know which block each equation lives in so they can find it fast.

How should you use the data booklet in the exam?

1. Know it before the exam. Work every practice problem with the booklet open, so you know where each equation sits without searching.
2. Know what it leaves out. It lists equations, not definitions, conditions or derivations. The kinematics equations, for example, only apply when acceleration is constant, and the booklet does not say so.
3. Know the symbols. Check what each symbol means in that topic, since the same letter can mean different quantities in different themes.
4. Use the constants as printed. Take values such as g and G from the booklet so your answer matches the markscheme.
5. Still show the equation. Write the equation you are using before substituting. A clearly written method gives the examiner something to award marks for, even if a later arithmetic slip costs the final answer.

Worked example: an IB-style kinematics problem

Here is an exam-style question from theme A.1, solved using only equations and constants from the data booklet.

A stone is thrown vertically upward at 12.0 m s⁻¹ from the edge of a cliff 25.0 m above the sea. Air resistance is negligible. (a) Calculate the maximum height of the stone above the cliff. (b) Determine the time the stone takes to reach the sea.

1. Choose a sign convention. Take upward as positive, so u = +12.0 m s⁻¹ and a = −9.8 m s⁻² (g from the data booklet). Acceleration is constant, so the kinematics equations apply.
2. Part (a): pick the equation without time. At the top, v = 0. Use v² = u² + 2as: 0 = 12.0² + 2 × (−9.8) × s.
3. Solve. 0 = 144 − 19.6s, so s = 144 ÷ 19.6 = 7.35 m above the cliff.
4. Part (b): set up the displacement. The sea is 25.0 m below the start, so s = −25.0 m. Use s = ut + ½at²: −25.0 = 12.0t − 4.9t².
5. Rearrange into a quadratic. 4.9t² − 12.0t − 25.0 = 0, so t = (12.0 + √(12.0² + 4 × 4.9 × 25.0)) ÷ (2 × 4.9) = (12.0 + √634) ÷ 9.8.
6. Solve and reject the negative root. √634 ≈ 25.18, so t ≈ 37.18 ÷ 9.8 ≈ 3.79 s.
7. Check another way. v² = u² + 2as gives v² = 144 + 2 × (−9.8) × (−25.0) = 634, so the stone hits the sea at about 25.2 m s⁻¹. Then v = u + at gives −25.18 = 12.0 − 9.8t, so t ≈ 3.79 s again.

The physics is the sign convention: once displacement and acceleration have consistent signs, one equation per part does the work. Most lost marks on questions like this come from a sign slip, not from the wrong equation.

Tutor tip: Our tutors teach students to derive the kinematics equations from a velocity-time graph. Once you can see that displacement is the area under the graph, you know when the equations apply and when they do not.

What is the IB Physics internal assessment?

The internal assessment (IA) is the scientific investigation: an open-ended task in which you gather and analyse data to answer your own research question. It is worth 20% of your grade at both SL and HL, uses about 10 hours of class time, and is written up as a report of no more than 3,000 words.

Charts, data tables, equations and calculations, citations, the bibliography and headers do not count toward the word limit. Your teacher marks the report and the IB moderates a sample.

How is the IB Physics IA marked?

What makes a strong IB Physics IA?

• A focused, quantitative question. The investigation must collect and analyse quantitative data, by changing an independent variable, selecting variables in fieldwork, or drawing on a database or simulation.
• Enough data to see a trend. A good range and interval for the independent variable, with repeats, matters more than a complicated apparatus.
• Uncertainties all the way through. Propagate them into processed values and show them on graphs, for example with error bars and maximum and minimum gradient lines.
• A link to theory. Compare your result with a published value or a physical model, and explain any disagreement.
• An honest evaluation. Name the weaknesses specific to your method, say which mattered most, and propose improvements that address them.

Collaboration is optional. Groups can be no larger than three, but each student must have their own research question and write their own report, and no two students may present the same set of raw data. Your teacher can comment on one draft before the final submission.

IB Physics IA example research questions

These are illustrative ideas to show the shape of a workable question, not IB exemplars. Each names an independent and a dependent variable inside a specific system.

• How does the drop height of a steel ball affect the diameter of the crater it makes in a tray of fine sand?
• How does the length of a vibrating string affect its fundamental frequency at constant tension?
• How does the temperature of a thermistor affect its resistance between 20 °C and 80 °C?
• How does the angle of release affect the range of a projectile launcher, and how well does the no-air-resistance model predict it?

What is the collaborative sciences project?

The collaborative sciences project is a group project, about 10 hours at SL and HL, in which students from different sciences work together on a real-world problem. It is part of the course for every IB science student but is not one of the graded components of your physics grade.

How does IB Physics affect the IB Diploma score?

Each of your six subjects is graded 1 to 7, and Theory of Knowledge and the Extended Essay add up to 3 more points, for a maximum of 45 (IB Diploma passing criteria). SL and HL grades count equally toward the total.

Several of the Diploma’s passing conditions make a weak Physics grade costly:

• At least 24 points in total.
• At least 12 points across HL subjects and at least 9 across SL subjects.
• No more than two grade 2s, and no more than three grades of 3 or below.

A 3 in HL Physics, for example, makes the 12-point HL requirement harder to reach with your other two HL subjects.

IB Physics vs AP Physics: what is the difference?

Both prepare students well for university science. The main differences are structure and scoring.

The AP Physics 1 exam, for example, gives 85 minutes for its multiple-choice section and 95 minutes for free response, each worth half the score (College Board AP Physics 1 exam). For the AP side in detail, see our guide to working with an AP Physics tutor. Students coming from the Cambridge system may also find our IGCSE Physics 0625 guide a useful bridge into IB.

How does a tutor help with IB Physics?

IB Physics asks for three different skills: understanding the physics, answering exam questions the way the markscheme expects, and running a real investigation. One-on-one tutoring can work on all three.

1. Find the real gap. Many lost marks trace back to algebra, trigonometry, vectors or unit conversions rather than the physics topic itself.
2. Teach the physics, not just the formula. Derive key equations so you know when they apply, then practise with the data booklet open.
3. Build paper technique. Timed Paper 1A practice, graph reading for Paper 1B, and multi-part Paper 2 questions with attention to command terms like “show”, “determine” and “explain”.
4. Plan and analyse the IA. Help choosing a workable research question, designing the data collection, processing uncertainties and writing an evaluation, while the work and writing stay yours.
5. Support HL extension topics. Rigid body mechanics, relativity, thermodynamics, induction and quantum physics are where HL students most often need a second explanation.
6. Review every lost mark. Go back through each past-paper error until the cause is clear.

“You never learn to search for what the problem is. Error analysis is very important for growth.”

Jake, Alexander Tutoring math tutor

At Alexander Tutoring, IB Physics students work one-on-one, online, with tutors who are working physicists, mathematicians and engineers with research experience, the same skills the IA asks for. Your first lesson is risk-free, and our Full Semester Guarantee means that if you are not satisfied at the end of the term, you get a full refund. Learn more about our online physics tutoring.

Tutor tip: Start a running list of every mark you lose on past papers and why. After a few papers, the same handful of mistakes usually explains most of them, and those are what to fix first. For more study habits, see how to get better at physics.

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