Command Terms

In IB Physics, a command term defines the task required by a question and indicates the expected depth of treatment. Read the complete question and use the command term, physical context and mark allocation to determine the physics, reasoning or working that should be presented.

The table below places the meaning of each command term alongside practical guidance on how to respond.

Command Terms Used in Examination Questions

Command term	What is required	How to respond
Draw	Represent the required information using a labelled, accurate diagram or graph.	Use a pencil and a ruler for straight lines. Draw diagrams to scale. Plot graph points accurately and join them with a straight line or smooth curve as appropriate.
State	Give a specific name, value or other brief answer without explanation or calculation.	Give the required answer directly and precisely.
Annotate	Add brief notes to a diagram or graph.	Place concise and relevant notes next to the corresponding part, data point or graph feature.
Calculate	Obtain a numerical answer and show the relevant stages in the working.	State the relationship used, rearrange where necessary and substitute the data. Give the final answer with appropriate significant figures, units and any required direction or sign.
Describe	Give a detailed account.	State the relevant features, what happens during the process or how the physical quantities change. Organise the information in a logical order.
Estimate	Obtain an approximate value.	Use a reasonable approximation, order of magnitude or simplifying condition, and give a result consistent with the precision of the estimate.
Outline	Give a brief account or summary.	Include the main features, stages or relationships without developing secondary details.
Analyse	Break down information to bring out its essential elements or structure.	Identify the relevant information in the data, graph, equation or physical context, and explain the relationships between its parts.
Determine	Obtain the only possible answer.	Use the information provided to reach a definite result through calculation, graph analysis or physical reasoning.
Discuss	Give a considered and balanced review of relevant arguments, factors or hypotheses.	Consider the main relevant factors and their effects. State the conclusion clearly and support it with appropriate physical reasoning or data.
Explain	Give a detailed account including reasons or causes.	Link the conditions, relevant physical principles, intermediate reasoning and result in a complete cause-and-effect sequence.
Predict	Give an expected result.	Use the relevant physical relationship, model, trend or condition to state the expected result.
Show	Give the steps in a calculation or derivation.	Begin with an appropriate relationship and include the necessary steps leading to the required result.
Sketch	Use a diagram or graph to represent the general shape or relationship and include the relevant features.	Show the correct overall shape, trend or relationship, and label axes, particular points or other key features as required.
Suggest	Propose a solution, hypothesis or other possible answer.	Give a reasonable possible answer that is consistent with the information provided and the relevant physics.

The official guide states that examination questions may also use terms that are not included in this list. In such cases, use the complete wording and context of the question to determine the required task.

Command Terms Used in the Scientific Investigation

The level descriptors for the scientific investigation use State, Identify, Outline, Describe, Explain and Justify. State, Outline, Describe and Explain are already included above. The two additional terms are defined below.

Command term	What is required	How to respond
Identify	Provide an answer from a number of possibilities.	State the required variable, feature, trend, source of error or other relevant item clearly.
Justify	Give valid reasons or evidence to support an answer or conclusion.	Support the judgement using relevant physical principles, data, calculations, experimental results or other valid evidence.

Answering Guidelines

When answering IB Physics questions:

• Read the complete question and address every object, physical quantity, stage and task that it specifies.
• Match the scope and depth of the response to the command term, physical context and mark allocation.
• Include only physics that is directly relevant to the question.
• Use complete physical statements that make the relevant quantities, conditions and relationships clear.
• Present independent information on separate lines where helpful. Present connected causes and consequences as a coherent line of reasoning.
• When an explanation is required, state the reason, physical mechanism or causal link and show how the relevant physical quantities are related.
• Select equations that apply under the conditions given in the question, and relate the quantities in the equation to the physical situation.
• In calculations, show the relevant working, including the necessary equation, rearrangement and substitution.
• Give numerical answers with appropriate significant figures and units, together with any required direction or sign.
• When using data or a graph, refer explicitly to relevant values, trends, gradients, intercepts, areas, maxima, minima or other features.
• Label diagrams and graphs clearly and correctly. Label graph axes with the relevant physical quantities and units.
• State the system, direction, reference point, initial conditions or assumptions when they affect the result.
• Use standard physical terminology and the symbols and units used in the guide and the data booklet.
• Distinguish between related but different physical quantities, such as distance and displacement, speed and velocity, mass and weight, and energy and power.
• Avoid isolated keywords, repeated information and material that does not answer the question.

Marks and Expected Scope

The mark allocation gives the total number of marks available for a question part and reflects the physics, reasoning or working that should be presented. The specific allocation of marks is given in the question-specific markscheme.

• A 1-mark question usually requires one clear and accurate name, value, relationship, direction, judgement or conclusion.
• A multi-mark question usually requires several relevant physical points, stages of reasoning, calculation steps or graph features.
• An explanation should include the reasons, physical mechanisms and causal links required by the question.
• A calculation should show the principal stages needed to obtain the answer and state the final result clearly.
• A data- or graph-based response should refer to specific data or graph features that support the answer.
• A question containing several requirements should address each requirement.
• The content and structure of the response should follow the command term, physical context and specific requirements of the question.

References

Reference: International Baccalaureate, Physics guide, first assessment 2025, pp. 76–77.

Additional references: International Baccalaureate, Physics guide, first assessment 2025, pp. 27–32, 60–65 and 71.

The question-specific markscheme determines how marks are awarded in an examination.

Send Feedback