Cambridge IGCSE Physics (0625) explains how motion, forces, energy, heat, waves, electricity, atoms and space behave. The subject becomes manageable when students link a physical situation to a correct model, choose the relevant relationship and check whether the result matches the evidence. This guide explains what students study, how the 2026–2028 examinations work and how to revise without relying on memorised answers.
The most useful way to understand IGCSE Physics is to ask four questions about any problem: What is happening? Which quantities describe it? What physical relationship connects them? How can the result be checked? A student who can answer these questions can adapt familiar concepts to unfamiliar diagrams, experiments and calculations.
Quick information for students: this article covers Cambridge International Physics syllabus 0625, examinations in 2026–2028. There are six main subject areas and three exam components per candidate. Core students take Papers 1, 3 and either 5 or 6. Extended students take Papers 2, 4 and either 5 or 6. The multiple-choice paper carries 30%, theory carries 50%, and practical assessment carries 20%. Confirm the awarding body, paper route and examination year with your school because other IGCSE Physics qualifications have different rules.
First, Check That Your Physics Course Is Cambridge 0625
‘IGCSE Physics’ describes a qualification type, not a single universal syllabus. A student might be studying Cambridge Physics 0625, a Cambridge 9–1 version, an Edexcel International GCSE or a combined science qualification. Content overlaps, but syllabus details and exam papers cannot be swapped casually.
The Cambridge 0625 syllabus for 2026, 2027 and 2028 is available through the official qualification page. Check the exam year rather than the year the course began. If your final examination will be in 2029, consult the separate 2029 document and relevant amendments.
Write down your syllabus code, intended examination session, Core or Extended route, practical paper, and any equipment your centre specifically permits. Review that record before buying a revision book or completing a full mock. This small step prevents an avoidable but common planning error.
The guide is independent educational advice. It does not claim to set Cambridge rules, predict examination questions or replace school instructions.
The Six Main Areas of the 2026–2028 Syllabus
Cambridge groups Physics 0625 content under six main headings. Each heading contains multiple smaller ideas and the full syllabus distinguishes Core statements from Supplement statements.
- Motion, forces and energy: speed, acceleration, interpreting motion graphs, forces, mass, weight, momentum where required, energy stores and transfers, work, power and pressure.
- Thermal physics: particle behaviour, thermal properties, temperature, heat transfer and explanations of thermal phenomena.
- Waves: wave characteristics, light, sound, electromagnetic radiation and relationships between quantities such as speed, frequency and wavelength.
- Electricity and magnetism: charge, current, voltage, resistance, circuits, electrical energy, magnetic effects and electromagnetic induction where required.
- Nuclear physics: atomic structure, ionising radiation, decay, hazards and uses of radiation in appropriate contexts.
- Space physics: astronomical objects, the Solar System, stars and wider space phenomena covered by the syllabus.
These are not separate rooms with locked doors. Energy crosses into almost every topic. A wave transfers energy; electrical devices transform energy; forces can change motion and energy; nuclear processes involve energy and radiation.
The first sign that a student understands Physics is the ability to explain connections between topics, not merely recite the six headings.
How Core and Extended Entry Works
The Cambridge 2026–2028 specification has Core and Extended routes. A Core candidate studies the Core content and sits the corresponding papers. An Extended candidate prepares Core material plus Supplement material and sits the Extended papers.
For this syllabus, Core entry is eligible for grades C to G. Extended entry is eligible for grades **A* to G**. This is an examination-entry rule, not an assessment of a student’s character or potential.
A student intending to compete for the highest grades must discuss Extended suitability with the school or examination centre early. Moving to Extended should be based on demonstrated understanding, practice evidence and sufficient time to learn the additional requirements, not wishful thinking.
A student who cannot consistently work with units, graphs or basic algebra may need foundational repair before advanced Physics questions become productive. These prerequisite skills are essential regardless of the final route.
All Six Paper Numbers Explained Correctly
Paper 1 – Multiple Choice (Core): 45 minutes, 40 marks and 30% of the qualification. There are 40 four-option multiple-choice questions using Core content.
Paper 3 – Theory (Core): 1 hour 15 minutes, 80 marks and 50%. It assesses Core knowledge through short-answer and structured questions.
Paper 2 – Multiple Choice (Extended): 45 minutes, 40 marks and 30%, based on Core plus Supplement content.
Paper 4 – Theory (Extended): 1 hour 15 minutes, 80 marks and 50%. It tests both understanding and application of Core and Supplement content.
Paper 5 – Practical Test: 1 hour 15 minutes, 40 marks and 20%. Students complete a practical assessment where available through the centre.
Paper 6 – Alternative to Practical: 1 hour, 40 marks and 20%. It is a written examination of experimental techniques, data handling and practical reasoning.
A Core candidate takes 1 + 3 + either 5 or 6. An Extended candidate takes 2 + 4 + either 5 or 6. Everyone takes three components, not six.
Paper 5 and Paper 6 assess the same broad scientific skill domain but in different ways. The school or centre should confirm the actual route entered.
What Physics Questions Are Trying to Measure
A routine exercise might say, ‘Calculate speed using the distance and time.’ An examination problem may instead describe an object moving between two points, provide a table and ask for an interpretation. Both relate to motion, but the second demands a decision about which quantities matter.
Most student difficulties occur at one of four stages: interpreting the words, choosing a physical model, operating the mathematics, or explaining the answer in context. Simply repeating the calculation step does not repair an interpretation problem.
Treat the question as a small scientific investigation. Identify the system, quantities and constraints. If a diagram is supplied, label it. If units appear, check whether they are consistent. If data come from an experiment, separate observation from theoretical expectation.
Physics rewards this disciplined process because a correct formula applied to the wrong situation is still a wrong solution.
Motion: Learn to Read What the Numbers Mean
Speed measures distance travelled per unit time. An object travelling 180 metres in 60 seconds has an average speed of 3 metres per second, since 180 ÷ 60 = 3.
That calculation is elementary. The real skill is deciding whether ‘distance’ or ‘displacement’ is required and whether the question asks for average speed, speed at an instant or another motion quantity.
A distance–time graph can reveal how distance changes over time. The gradient of a straight segment gives the corresponding speed in appropriate units. A horizontal segment means the recorded distance is not changing. A curved graph requires care because the gradient changes.
A speed–time graph shows speed changing with time. Its gradient indicates acceleration in the appropriate context; the area under a speed–time graph gives distance travelled. Do not automatically apply interpretations from one kind of graph to another.
Students should practise sketching the physical story from a graph and sketching the corresponding graph from a short physical story. This two-way translation develops understanding.
Forces: The Diagram Comes Before the Formula
A force can change motion or deform an object. Before writing an equation, determine which forces act on the system and their directions. Distinguish the object of interest from the surrounding environment.
For a simple horizontal push, resistive forces may oppose the applied force. If the forces balance, the resultant force is zero. That does not mean the object must be stationary: it can continue moving at constant velocity when the overall force is zero.
If there is a non-zero resultant force, the motion changes according to the relevant laws and conditions. In suitable questions using Newton’s second law, resultant force = mass × acceleration.
If an object of mass 4 kg has acceleration 2 m/s² from the resultant force, then the resultant force is 8 N. The answer is not necessarily the size of a single applied force unless the question says that force is the only unbalanced one.
A frequent mistake is treating mass and weight as the same quantity. Mass is measured in kilograms; weight is a force measured in newtons. The relationship between them depends on gravitational field strength.
Energy: Follow the Transfer Rather Than Saying It Vanishes
Energy is useful because it links many physical situations. When a ball is raised, work is done against gravity and its gravitational potential energy increases. When it falls, energy is transferred between stores, with some transferred to the surroundings through processes such as air resistance.
Students often write ‘energy is lost’. In a school-level explanation, it is more accurate to identify where energy was transferred and why it becomes less useful for the intended purpose.
A useful device calculation may ask for efficiency. If an appliance receives 500 J of energy and delivers 350 J usefully, its efficiency = useful output ÷ input × 100% = 70%.
But the percentage alone is not the explanation. The student should identify the useful output, how the remaining energy is transferred and the condition that makes the comparison meaningful.
Likewise, power measures the rate of energy transfer. A high-power device transfers energy more quickly, not necessarily with greater efficiency. Keep energy, power and efficiency conceptually separate.
Thermal Physics: Why Particle Reasoning Matters
Temperature, internal energy and heat transfer are related but not synonymous. A good answer identifies what is being measured and the physical process that changes it.
For a solid heated towards melting, particles gain energy and the arrangement can change as the material reaches the conditions for phase transition. A temperature–time graph may show a region where energy transfer occurs without a simple rise in temperature during melting.
Conduction, convection and thermal radiation require different explanations. Conduction involves transfer through interactions in a material. Convection depends on bulk movement in fluids. Thermal radiation involves electromagnetic radiation and does not require matter between source and receiver.
A common error is describing any heat transfer as ‘convection’ because warm material rises. In an experiment involving a metal rod, the relevant mechanism may instead be conduction.
For each explanation, name the mechanism, the material or space involved and the evidence that supports the conclusion.
Waves: Interpret Amplitude, Frequency and Wavelength
Wave questions require students to connect a diagram with a physical phenomenon. Amplitude indicates the maximum displacement from the equilibrium position in the relevant representation. Wavelength is a spatial length between corresponding points on successive cycles. Frequency tells how many cycles occur per second.
For a wave travelling at speed 12 m/s with frequency 4 Hz, the wavelength is 3 m, because speed = frequency × wavelength.
The unit check helps: hertz means per second, and multiplying per-second by metres produces metres per second. A result in the wrong units often signals a mistaken rearrangement.
Students should separate properties of the wave from properties of its source or medium. A sound wave needs a medium. Electromagnetic waves can travel through a vacuum. These distinctions matter in questions that compare sound and light.
When drawing rays or wave diagrams, follow the conventions of the syllabus and label the actual physical quantities rather than relying on a memorised picture with no explanation.
Electricity: Trace the Circuit Path
Electricity becomes easier when students stop treating circuit symbols as decorations and start reasoning about complete paths, charges, energy and the function of components.
Current is the rate of flow of charge. Potential difference relates to energy transferred per unit charge. Resistance concerns how a component affects current for the potential difference across it. They are related, but they are not interchangeable.
For a suitable resistor obeying V = IR, if the potential difference is 6 V and current is 0.5 A, the resistance is 12 Ω. Check by multiplying 0.5 × 12 to recover 6 V.
In a simple series circuit, current is the same through each element in the single path. In a parallel arrangement, current divides between branches according to the conditions. Students should not apply the series rule to every parallel circuit by habit.
To solve a circuit question, draw or trace the paths, mark known readings and decide whether the question concerns current, voltage, resistance or energy. Only then choose a formula.
Nuclear Physics: Differentiate Activity From Risk
Students learn about atoms, unstable nuclei, types of ionising radiation and nuclear processes. The key habit is to connect a particular radiation type or nuclear change to its actual properties and the task at hand.
An isotope is identified through proton number and neutron number; isotopes of the same element have the same number of protons but different numbers of neutrons.
Radioactive decay is a statistical process. Half-life is the time required for the activity or number of undecayed nuclei in a large sample to fall to half the starting value, under the usual model. It does not mean every individual nucleus waits the same amount of time.
Consider a sample with an activity of 800 counts per unit time above background. After one half-life, the expected activity is 400 in the simple idealised model; after another, 200. Actual measurements can fluctuate and require background-rate considerations.
Distinguish irradiation from contamination, and avoid treating all radiation as having identical penetration and ionising effects. Any practical work involving radiation must follow formal laboratory safety rules rather than improvised home experiments.
Space Physics: Build a Model of Scale
Space physics links familiar motion and energy concepts to astronomical scales. Students encounter the Solar System, stars and larger structures, with the particular requirements defined by Cambridge 0625.
A common problem is mixing up the words rotation and orbit, or confusing the apparent movement of objects in the sky with the actual movement of the bodies involved. Draw a simple schematic to separate the motions.
When discussing distances, identify the unit and its meaning. A light-year is a unit of distance, not a unit of time, despite the word ‘year’.
Use scale cautiously. A small textbook diagram cannot usually show both planet sizes and orbital separations accurately. Ask which feature the drawing is intended to represent.
Space physics is not a separate memory exercise; it is an opportunity to apply physical models to unfamiliar environments and scales.
The Calculation Routine That Prevents Avoidable Errors
A strong numerical answer usually follows the same sequence. Students should practise it as a routine and then shorten the presentation where the question requires less working.
- Identify the target quantity. Write what the question is asking for, including its unit.
- Select the physical relationship. Confirm that the formula fits the given system and conditions.
- Convert units. Change centimetres to metres or minutes to seconds when required before calculating.
- Rearrange symbolically where practical. Avoid premature substitution when it creates unnecessary arithmetic confusion.
- Substitute and calculate. Keep enough precision through intermediate steps.
- Check the scale and unit. Compare the result with the original situation and any reasonable estimate.
For example, an object moving 1.2 kilometres in 4 minutes covers 1200 metres in 240 seconds. Its average speed is 5 m/s. Dividing 1.2 by 4 to produce 0.3 and labelling the answer ‘m/s’ would be a unit error, not a Physics discovery.
A good mistake log distinguishes a formula-selection error from a conversion error. They require different repairs.
Graph Skills: What the Shape Does and Does Not Prove
Examination graphs may represent motion, cooling, electrical relationships or experimental measurements. In every case, start with the title, axes, units, scale and plotted values.
A line that appears straight may indicate a relationship in the measured range, but the interpretation depends on what each axis represents. Two quantities may be correlated without the graph proving the mechanism behind the correlation.
When asked for a gradient, use a large clear triangle appropriate to the graph, state the quantities and calculate with units. When asked for an anomalous reading, identify it relative to the overall pattern and explain why it needs review.
Graph quality is part of scientific communication. Clear axes and sensible scales make the data interpretable; decorative complexity does not.
Students can practise by drawing a graph from a small table, extracting a point from the graph and explaining one supported conclusion plus one limitation.
Practical Paper 5 and Paper 6: Both Require Scientific Thinking
The practical route deserves planned preparation because it contributes 20% of the assessment. Paper 5 and Paper 6 are not identical, but both test understanding of variables, measurement, results and investigation quality.
A physical experiment might measure the time for a moving object to cover a distance. Students need to recognise what changes, what is measured, which quantities are kept consistent and how repeats reduce uncertainty from timing variation.
For a pendulum investigation, timing a number of oscillations and dividing by the number can help estimate a period more reliably than timing one oscillation. The design still needs the appropriate controlled variables and safe apparatus.
Paper 6 may present an experimental setup in words or a diagram and ask how measurements should be taken, plotted or evaluated. A student who never thinks about real experimental limitations is at a disadvantage, even without a hands-on paper.
Do not use household electrical supply or other hazardous equipment for unsupervised experiments. Practical learning should use school-approved procedures and supervised equipment.
Measurements, Accuracy and Uncertainty
Measurements are never just numbers. They have units, instrument limitations and often repeated observations. Understanding these details improves both practical answers and interpretation of experimental results.
If a ruler can only be read to a certain resolution, recording a measurement to excessive decimal places creates false precision. If the starting point of a length is offset, an otherwise careful reading can be systematically wrong.
Random variation and systematic error are not the same. Repeated readings can reveal scatter and help estimate a mean, but they will not automatically remove a systematic calibration offset.
An improvement should address a named weakness. ‘Repeat the reading to reduce the influence of random timing errors’ is useful when the problem is repeatability. It is not the appropriate solution for a device whose zero is incorrectly set.
When an exam asks whether evidence supports a conclusion, compare the uncertainty with the size of the observed effect before claiming that two values are meaningfully different.
Multiple Choice and Structured Questions Need Different Practice
The multiple-choice paper uses four-option questions. Reading quickly is useful, but guessing by keyword is unreliable. Work out what physical quantity or rule the stem requires, then test the options.
Eliminate answers with impossible units, inconsistent directions or implausible magnitude where appropriate. A numerical distractor may represent a common conversion or rearrangement error.
Structured theory questions require students to show reasoning and communicate precisely. A numerical final answer with no appropriate working may miss evidence of method; a long paragraph without the requested physical relationship may also be unhelpful.
Read command words accurately. State asks for a concise fact. Describe asks what happens. Explain asks why. Calculate asks for a numerical result supported by the required method. Suggest calls for a plausible idea justified by the context.
A strong student learns to match the response to the task and the available marks.
Common Physics Mistakes and Their Specific Repairs
- Wrong quantity: using distance when displacement is required. Repair by defining the quantity before substituting.
- Units left unchanged: mixing minutes and seconds, or centimetres and metres. Repair by writing conversions before the equation.
- Formula without model: choosing the first familiar equation despite mismatched conditions. Repair with a one-line physical explanation.
- Graph confusion: transferring a distance–time graph rule to a speed–time graph. Repair by discussing the axes separately.
- Direction confusion: missing that force and acceleration have directions. Repair by drawing labelled arrows.
- Energy-language confusion: saying energy disappeared instead of naming transfers. Repair with a system-boundary description.
- Overprecise results: claiming more significant figures than measurements justify. Repair by checking source precision and question instructions.
- Experiment without controls: changing more than one factor. Repair by defining independent, dependent and controlled variables.
A generic instruction to ‘be more careful’ rarely fixes these mistakes. Each error should lead to one specific exercise that tests whether the problem is resolved.
Repair, Stabilise and Extend: The Three Learning Paths
Students who need repair should begin with prerequisite mathematics, measurement, graphs and elementary physical concepts. If negative numbers or algebraic rearrangement is unreliable, the student will struggle even when the Physics idea is understood.
Students who need stabilisation should practise mixed questions after a delay. A student may solve every forces question within the forces chapter but fail to recognise a forces problem in a mixed examination. Interleaving makes the method more retrievable.
Students who are ready for extension can compare competing models, explain assumptions, evaluate the usefulness of approximations and solve unfamiliar multi-step problems. Extension should deepen interpretation instead of merely increasing the number of formulas.
A student can be strong in electricity and weak in waves. Diagnose the actual topic and cognitive skill rather than applying a single label to the learner.
A Four-Session Weekly Physics Routine
Session one: conceptual model. Choose one physical process. Explain it in ordinary language, then use precise terms, diagrams and units. Finish with two independent questions.
Session two: numerical method. Practise selecting equations, converting units and checking plausible results. Mix at least one older topic with the current topic.
Session three: graphs and practical skills. Interpret a new data set, evaluate an investigation and explain one limitation or improvement.
Session four: retrieval and correction. Reattempt previously missed questions after time has passed. Work on the cause of errors rather than completing another unreviewed paper.
The ideal duration depends on the student’s school load and attention. Regular, focused practice with feedback is more valuable than a heroic timetable that cannot be maintained.
A Twelve-Week Preparation Roadmap
Weeks 1–2: establish the baseline. Confirm 0625, examination year, tier and practical route. Sample the six topic groups and basic calculations. Separate knowledge errors from mathematical or reading errors.
Weeks 3–5: rebuild foundations. Prioritise units, graphs, speed, forces, energy and basic circuits according to diagnostic results. Explain processes before rehearsing formula substitutions.
Weeks 6–8: integrate. Connect waves, thermal physics, nuclear and space topics to earlier ideas. Use mixed short-answer questions and introduce more practical reasoning.
Weeks 9–10: rehearse paper conditions. Attempt selected current-specification components with authentic timing. Mark carefully and track time loss as well as wrong answers.
Weeks 11–12: consolidate, not panic. Return to recurring errors, practise the practical assessment route and use full papers selectively. Check the official syllabus one final time for updates.
This timetable is a teaching suggestion, not a claim about Cambridge’s official course duration or a guarantee of grade improvement.
How to Use Official Syllabus Documents and Past Papers
Cambridge’s IGCSE Physics (0625) qualification page is the primary reference. The 2026–2028 syllabus sets out subject statements, examination components and skills.
Some older papers remain useful for practising stable concepts, but they should not override the latest examination-year rules. Identify the paper code, year and component before timing a full paper.
After marking a question, ask what went wrong first: physical model, data reading, units, arithmetic, explanation or timing? Write one correction sentence and reattempt later without the mark scheme.
Students taking other science subjects can also use How IGCSE Biology Works, How IGCSE Chemistry Works and How IGCSE Mathematics Works, while keeping the separate syllabus specifications clear.
Frequently Asked Questions
How many Physics papers does a Cambridge 0625 student sit?
Three. Core takes Papers 1 and 3 plus Paper 5 or 6. Extended takes Papers 2 and 4 plus Paper 5 or 6 under the 2026–2028 syllabus.
Is Physics mostly mathematics?
Mathematics is an important tool, but Physics also requires selecting models, explaining mechanisms, interpreting data and evaluating experiments. Correct arithmetic does not guarantee a correct physical interpretation.
What if I understand a lesson but forget during a test?
Include delayed retrieval and mixed problems in revision. Build the habit of interpreting the question before choosing a formula, and keep an error log that reveals which kind of memory or method failure occurs.
Is Paper 6 a way to skip practical knowledge?
No. It assesses experimental reasoning in a written format. Measurement, variables, graphs, limitations and safe procedures are still important.
Can Core students achieve an A*?
Not through the published Core entry route for 2026–2028, whose eligible range is C–G. Extended eligibility should be discussed with the centre.
Should I memorise every formula without understanding it?
Learn the meaning, variables and conditions of important relationships. Check the current Cambridge syllabus for any formulas supplied in examinations. No formula list substitutes for choosing the right model.
Is a long explanation better than a short one?
The best explanation is accurate, relevant and sufficient for the question. Extra words that do not explain the mechanism can waste time or introduce contradictions.
Student Checklist Before Examination Day
- I know the correct Physics syllabus, examination year and tier.
- I know which three papers I am taking and the weight of each.
- I can distinguish quantities such as distance, displacement, mass, weight, energy and power.
- I can convert units, rearrange equations and check numerical plausibility.
- I can interpret distance–time and speed–time graphs correctly.
- I can explain core physical processes using a clear cause-and-effect chain.
- I can interpret an experiment, choose controls and discuss uncertainty.
- I revisit misconceptions instead of only collecting more past papers.
- I use the official Cambridge specification to confirm changes.
IGCSE Physics works when a student can move confidently between the world, a physical model, a mathematical representation and real evidence. The objective is not a collection of memorised formulas. It is independent reasoning that survives unfamiliar questions and examination pressure.
Official source: Cambridge IGCSE Physics (0625). This eduKateSG student guide is independent educational commentary.
More IGCSE Student Guides
Explore the next guides in the eduKateSG IGCSE series. Check each guide’s examination year and Cambridge syllabus code before using paper details.