Cambridge IGCSE Physics (code 0625) asks you to explain how the physical world behaves using relationships, graphs and clear reasoning. It is less about remembering facts than about choosing the right idea for a situation, and then showing it in units and steps.
This guide gives you the shape of the subject, a study order through every module on this site, the difficulties students meet most, and how to decide when extra help is worth having.
What is IGCSE Physics, and what does the code mean?
The code used here is 0625, published by Cambridge. Cambridge changes syllabus details by exam year, so treat this page as a map and treat the Cambridge page as the authority for scope, tiers, paper structure and any practical or alternative route.
Your school or exam centre controls entry, registration and results, and it also confirms which version applies to you. Use our syllabus and exam-year navigator to build a checking list of what to confirm, and read the 0625 code and exam-year guide before you plan revision.
How is the subject built?
Think of Physics as three layers that appear in every topic.
- Ideas: what a quantity means, such as speed, force, pressure, current or half-life.
- Relationships: equations, proportionality and graph features that link those quantities.
- Reasoning: choosing the relationship for a situation, carrying units, stating assumptions, and explaining in a chain of cause and effect.
Exam questions test all three. A typical lost mark is at layer three: the student knows the equation but picks it before understanding the situation, or writes a number without the unit that would have revealed the mistake.
In what order should I study the topics?
The order below follows how skills build. Each module page lists its lessons and a practice set. Your school may teach in another order, so use this as a revision route as well.
Start here: measurement and motion
- Measurement and quantities: units, scales, means, vectors and uncertainty. Every later topic uses these habits.
- Motion and graphs: speed, acceleration, and how gradient and area work on graphs. This is the graph-reading foundation for the whole subject.
Forces and the mechanics of objects
- Forces and momentum: direction, resultant force and change in motion.
- Mass, weight and density: three quantities that are easy to mix up.
- Moments and stability: turning effects and balance.
- Pressure in solids and fluids: force spread over area, and what changes with depth.
Energy and thermal physics
- Work, energy and efficiency: how energy is stored and transferred.
- Power and energy resources: rate of energy transfer and resource comparison.
- Thermal processes: conduction, convection, radiation and particle models.
- Heat calculations: specific heat capacity and related calculations.
Waves, light and sound
- Wave behaviour: wavelength, frequency, speed and wave effects.
- Light and imaging: reflection, refraction and ray diagrams.
- Electromagnetic spectrum and sound: types of radiation and how sound differs from light.
Electricity and magnetism
- Charge and current: what moves, and how it is measured.
- Potential difference, resistance and circuits: series, parallel and reading circuit graphs.
- Electrical energy and safe interpretation: power, energy units and sensible safety reasoning.
- Magnetism and fields: field patterns and forces.
- Induction and transformers: how changing fields produce voltage.
Atoms, nuclei and space
- Atomic and nuclear models: structure and radiation.
- Half-life and background: reading decay data and handling background radiation.
- Space physics: the Solar System and the wider universe.
Across every topic
- Physics investigations and explanations: planning, graphs, conclusions and written explanations. Work on this module alongside the others, not only at the end.
What are the most common difficulties?
Students usually report one of these. Each has a short guide with original examples.
- Jumping to an equation before understanding the picture: choosing a formula before drawing the situation.
- Confusing distance with displacement on motion graphs: distance and displacement in motion graphs.
- Converting energy units wrongly, such as kilowatt-hours and joules: unit conversion in electrical energy.
- Using gradient when the question needs area, or the reverse: gradient versus area on a graph.
- Writing a force as a number without a direction: describing forces with direction.
- Being unable to turn a diagram into a written explanation: connecting a diagram to an explanation.
The bounds and rounding explainer and the triangle and bearings reasoning board also help you practise stating assumptions and choosing a model before you calculate.
How should I study Physics well?
A routine that works is short and repeatable. Do it after each topic.
- Write a one-line meaning and a unit for each quantity. If you cannot, the formula will not help you.
- Sketch the situation before choosing a relationship. Label directions and known values.
- Predict the size or sign of the answer. Is it positive, larger than 1, in metres or centimetres?
- Calculate with units on every line. A wrong unit is a free warning.
- Explain in a sentence what the answer means for the object or circuit.
- Keep an error log with three columns: what I did, what went wrong, what I will check next time.
Use the original practice section for mixed questions with explained answers, and the revision guide to plan around real gaps instead of rereading everything.
What does one-to-one teaching add?
Reading explains what is correct. A teacher watches what you actually do with a question, and can stop you at the moment you choose a formula too early. That kind of correction is hard to get from a book, because the book cannot see your working.
If you want to try it, online one-to-one Physics tuition starts with a paid one-hour trial at the assigned teacher’s confirmed rate, from RM80. If you are not sure yet, considering Physics tuition explains when self-study or group classes are enough.