Q: What does Cambridge IGCSE Physics Paper 6 assess? A: Paper 6 is the one-hour Alternative to Practical paper. Candidates do not perform experiments during the paper, but Cambridge tests the same AO3 experimental skills and contexts as Paper 5.
TL;DR For the 2026-2028 Physics syllabuses, Paper 6 has 40 marks, contributes 20%, and contains compulsory questions. It tests practical reasoning through written material rather than candidate-run experiments. Confirm your syllabus code and paper entry with your centre instead of assuming that private-candidate status automatically means Paper 6.
Last reviewed: 20 August 2026. This guide is bounded to Cambridge's published 0625 and 0972 specifications. A syllabus lists assessable skills and contexts, not the exact questions that will appear in a future paper.
1. Paper 6 at a glance
Feature
Published 2026-2028 position
Paper name
Alternative to Practical
Duration
1 hour
Marks
40
Weighting
20%
Assessment objective
AO3 Experimental skills and investigations
Candidate-run experiments in the paper
No
Check this topic from memory
Attempt the matching topic bank before reopening the notes. Use each missed idea to decide what to review next.
All candidates take one practical paper from a choice of Paper 5 or Paper 6. Cambridge says the two papers require the same experimental skills, require understanding of the same experimental contexts, and test the same assessment objective.
That equivalence does not make the papers identical. Paper 5 requires candidates to perform experiments in a laboratory. Paper 6 presents the practical work through questions, diagrams, readings, observations, tables, or other supplied material.
2. Confirm the entry before choosing resources
Do not infer the practical paper from whether the candidate studies privately, attends an international school, or has access to a laboratory elsewhere. The centre makes and administers the examination entry.
Ask the centre to confirm in writing:
the syllabus code, 0625 or 0972;
the examination series and administrative zone;
whether the entry uses Paper 5 or Paper 6;
the final component code on the Statement of Entry;
any centre deadlines and local arrangements.
Cambridge describes 0972 as graded 9 to 1 and otherwise the same as 0625, but 0972 is available only in specified administrative zones. The published availability notice and the candidate's actual entry matter more than a general assumption about location.
3. The AO3 skills Cambridge may assess
The current syllabus groups AO3 into five areas.
Selecting and using techniques, apparatus, and materials
Candidates may need to identify apparatus from a diagram or description, complete or label a diagram, explain how apparatus is used, choose an appropriate method, address a hazard, or explain how accuracy can be improved.
Planning experiments and investigations
The specification includes identifying independent and dependent variables, explaining controlled variables, choosing a suitable number and range of values, selecting apparatus, describing a procedure, addressing risk, recording results, processing results, and making a reasoned prediction.
Cambridge does not publish one mandatory planning template. A response should answer the particular task instead of forcing every plan into a memorised paragraph.
Making and recording measurements
Candidates may read analogue or digital apparatus, interpolate to the nearest half-scale division where required, correct a zero error where required, repeat measurements where appropriate, and record values systematically with suitable precision and units.
Interpreting and evaluating data
This includes calculations, graphing, gradients and intercepts, conclusions supported by data, anomalous results, and whether values agree within experimental accuracy. For this syllabus, Cambridge states that experimental accuracy may be assumed to be plus or minus 10% when a question asks whether results are equal within its limits.
Evaluating methods and improvements
Candidates may identify measurement, random, or systematic error, explain a source of uncertainty, evaluate the control of variables, and suggest a change to the apparatus or method. A generic phrase such as "human error" does not identify which measurement or procedure is limited.
4. Published experimental contexts
Cambridge says candidates should be familiar with practical work involving:
measurement of quantities such as length, volume, and force;
small distances or short time intervals;
derived quantities, such as spring extension per unit load or resistance;
relationships between two variables;
comparisons of measured or derived quantities;
heating, cooling, and temperature measurement;
springs, balances, motion, and oscillations;
electric circuits, including current and potential difference;
optics using items such as pins, mirrors, prisms, lenses, and transparent or opaque blocks;
unfamiliar procedures using simple apparatus.
These are syllabus contexts, not a prediction that every paper will contain one mechanics, one electricity, one optics, and one thermal question. Past-paper patterns can change and should not replace the current specification.
5. Readings, tables, and graphs
Cambridge publishes specific data-presentation conventions.
Read a scale to one half of its smallest division when interpolation is required.
Record a measured value at a precision supported by the instrument.
Put the quantity and unit in a table heading, such as time / s, rather than repeating the unit in each data cell.
Repeat a reading where appropriate.
Label each graph axis with the quantity and unit.
Unless instructed otherwise, use more than half the grid in both directions and choose a sensible scale.
Mark points clearly and plot them within half a small square.
Draw one thin, smooth best-fit line or curve by inspection.
Ignore a clearly anomalous point only when it has been identified as anomalous.
The specification does not say that every graph requires a gradient triangle or that a gradient always has units. Follow the actual question and the dimensions of the plotted quantities.
6. A source-bounded preparation method
The following is study advice, not a Cambridge rule.
Verify the component code before selecting papers.
Use papers from the applicable syllabus and check that they reflect the current 2026-2028 content.
Tag each error by the relevant AO3 skill: apparatus, planning, measurement, data, or evaluation.
Practise reading the scale actually shown instead of applying a fixed number of decimal places to every instrument.
Redraw tables and graphs using Cambridge's published conventions.
For an evaluation, name the limited step, explain its effect, and propose a change that addresses that limitation.
Complete timed work only after the underlying skill errors are understood.
Cambridge says learners should develop practical skills through practical work and investigations. Handling apparatus can therefore support the course, even when the examination entry is Paper 6. It does not follow that one particular commercial course, number of laboratory sessions, or mock-paper schedule is required.
7. What this guide does not establish
The syllabus does not establish:
which component a particular Singapore centre will offer;
that all private candidates take Paper 6;
the exact experiments or question order in a future paper;
a guaranteed recurring topic pattern;
a fixed number of past papers needed for a grade;
grade improvement from laboratory tuition or any other preparation format.
Use the syllabus for the assessment contract, the centre for the candidate's entry, and the live examination documents for series-specific administration.
Worked application: turn evidence into a conclusion
Suppose a candidate investigates how one controlled change affects a measured physics quantity in IGCSE Physics Paper 6 (Alternative to Practical): Current 0625 / 0972 Guide. The plan names the independent variable, gives a sensible range with at least five values and states how the dependent variable is measured. Other relevant factors are held constant. Raw readings are recorded with units and consistent precision, repeated where scatter is plausible, then processed into a graph or derived quantity. The conclusion describes the observed relationship and cites the trend rather than saying only that the prediction was correct. An evaluation identifies a specific limitation, explains its likely effect and proposes a practical improvement that directly reduces that limitation.
Connect planning, measurement and evaluation
The strongest practical answers form one chain. The question determines the variables; the variables determine the apparatus and range; the apparatus determines resolution and plausible uncertainty; and the intended relationship determines the table, graph and calculation. Plan the analysis before collecting data so every required raw measurement is recorded. A derived quantity cannot be recovered reliably if one of its component readings was never taken.
Use repeat readings to expose random variation, not as a ritual. Repeats are most useful when a reading is difficult to judge, a time interval is short or the system fluctuates. If repeats are close, calculate a mean. If one value is anomalous, investigate it and repeat that condition rather than deleting it without justification. A zero error affects every reading systematically and is corrected differently from scatter.
Evaluation should name the route from limitation to effect. For example, a broad pointer makes a length endpoint uncertain, which creates scatter in the calculated gradient; replacing it with a thin fiducial marker reduces that reading uncertainty. Saying only "use better equipment" does not identify what becomes better or why the evidence improves.
Common misconceptions and corrections
Changing several variables together. Vary only the independent variable and control the other relevant factors.
Recording only processed values. Keep the raw readings, units and consistent precision needed to audit every calculation.
Drawing a dot-to-dot graph. Use an appropriate best-fit line or curve and identify anomalies from the overall pattern.
Calling every difference human error. Name the physical or measurement cause and explain its effect on the result.
Offering an improvement with no causal link. State the limitation, its consequence and how the change reduces it.
Assessment guidance
Paper 5 and Paper 6 assess the same AO3 reasoning even though one uses laboratory work and the other supplies experimental information. Read scales to the requested precision, include units in table headings and use most of the graph grid with a simple scale. Show gradient triangles and calculations clearly. Conclusions must refer to observations or numerical trends. Planning answers need operational steps, a suitable range, control variables, safety where relevant and a stated analysis method. Evaluation marks reward specific, feasible improvements linked to identified limitations, not generic instructions to repeat or be more careful.
Retrieval practice
Redesign the worked application for three different independent variables. For each version, list apparatus with range or resolution, five values, control variables, raw table headings, the expected graph and one safety control. Then diagnose one random and one systematic error, calculate a mean with an anomaly, describe a best-fit trend and write two limitation-effect-improvement chains.
