A-Level Physics Essay Questions: There are no essay questions. How to write written response questions, along with the official definitions of command words from Cambridge and Edexcel.

First, a clarification: A-Level Physics has no essay papers, nor are there essay questions. However, both exam boards include questions requiring written responses in their theory papers: Cambridge 9702's structured questions often feature sub-questions like Explain, Describe, and Suggest; the Edexcel IAL syllabus specifies that unit papers may include "extended-writing questions". For the rules on calculation questions (including Show that), see Physics Calculation Questions; for practical questions, see Physics Practical. This article focuses on written questions: the official definitions of command words by both boards, what the assessment objectives imply, and how to answer them. This is based on the Cambridge 9702 (2025–2027) and Pearson IAL Physics (3rd Edition) syllabuses.

1. Where Are the Written Questions?

• Cambridge 9702: Paper 2 (AS) and Paper 4 (A Level) are structured questions, with written questions distributed across the sub-questions;
• Edexcel IAL: The syllabus specifies that theory unit (Units 1, 2, 4, 5) papers may include multiple-choice, short-answer, open-response, calculation, and extended-writing questions; practical unit (Units 3 and 6) papers may also include extended-writing questions.

Cambridge Assessment Objective Weightings: Papers 1, 2, and 4 are all 50% AO1 (Knowledge and Understanding) and 50% AO2 (Handling, Applying, and Evaluating Information) (AO3 (Experimental Skills) is only assessed in Papers 3 and 5). The syllabus describes AO1 as including mastery of "scientific vocabulary, terminology, and conventions," and AO2 as including "translating information from one form to another" and "handling, applying, and evaluating information using words or other forms." In other words, expressing ideas in accurate physics language is itself part of the scoring requirements.

2. Command Words: Definitions from Both Exam Boards

Definitions from the Cambridge syllabus (excerpt):

• Describe: State the main points, giving features and characteristics;
• Explain: Give the purpose or reason, clarify the relationship between things, explain why and/or how, and support with relevant evidence;
• Suggest: Apply knowledge and understanding to propose a suggestion in a situation with multiple plausible answers;
• Define: Give the exact meaning; State: Express clearly;
• Compare: Identify or comment on similarities and/or differences; Comment: Give a reasoned opinion; Justify: Support a point of view with evidence or reasoning; Predict: Deduce what might happen based on given information; Determine: Find the answer using given information.

The "Command Word Table" in the Edexcel syllabus is more specific and particularly useful for written questions (excerpt):

Looking at both definitions together, the most important distinction is: Describe tells "what," while Explain tells "why." Answering an Explain question by only describing the phenomenon without giving the reason is the most common way to lose marks (based on empirical judgment).

3. Common Types of Written Questions

The following examples are based on syllabus content, and the writing approaches are empirical suggestions:

1. Definition Questions

Use complete sentences, include all keywords, and state conditions when necessary. For example, when defining a physical quantity, clarify it as "the [quantity] per unit [something]," and note that vectors require specifying direction. Definitions must be memorized accurately, but you should be able to explain the conditions and scope of application in your own words.

2. Explaining Phenomena

Write it as a causal chain: Cause → Physics Principle → Effect. Take the photoelectric effect required by the Cambridge syllabus as an example (see Article 177): to explain why the maximum kinetic energy of photoelectrons is independent of light intensity, you must include "one photon interacts with only one electron," "photon energy is determined solely by frequency," and "maximum kinetic energy equals photon energy minus work function," while light intensity only affects the number of photons per unit time.

3. Describing Experiments or Processes

Write step-by-step, clearly stating what to measure, how to measure it, and how to reduce errors; draw diagrams to assist (for practical question conventions, see Article 185).

4. Comparison Questions

Write in pairs: address both sides for each point. According to Edexcel's definition, include at least one similarity and one difference.

5. Evaluation and Suggestion Questions (Suggest, Evaluate, Criticise)

Combine the context or data given in the question to explain strengths and weaknesses, and provide a reasoned judgment; for Suggest questions, you can propose ideas not directly learned but physically reasonable.

4. How to Write Answers

Here are some empirical suggestions:

1. Write points according to marks: A question worth a certain number of marks generally requires that many distinct points, with each point clearly stated in one sentence;
2. Use physics terminology: For example, use "conservation of momentum," "potential difference," "resonance," and "half-life" instead of everyday expressions;
3. Show relationships between physical quantities: You can use formulas to assist, such as "from P = IV, we know..."; Edexcel also explicitly states that Explain can include mathematical explanations;
4. Refer back to the question context: If the question provides an apparatus, data, or a diagram, your answer must use them;
5. Practice expressing in English: Since the exam is in English, practice writing complete explanations of common phenomena in English, especially topics rarely covered in domestic high schools (such as medical physics, astrophysics, and particle physics).

5. Common Reasons for Losing Marks

Here is an empirical summary:

• For Explain questions, only describing without explaining the reason;
• Skipping steps in the causal chain, jumping directly from cause to conclusion;
• Inaccurate terminology, such as confusing "force" with "energy" or "current" with "voltage";
• For comparison questions, only writing about one side or only writing differences;
• Answers that are disconnected from the context given in the question.

Conclusion

Physics has no essay questions, but written questions carry significant weight in the theory papers of both exam boards. Cambridge's assessment objectives list scientific terminology and information expression as scoring requirements, while Edexcel's command word table details requirements like Describe, Explain, and Compare and contrast. By distinguishing between description and explanation, writing complete causal chains, using accurate terminology, and referring back to the question context, you can turn written questions from "knowing how to do it but losing marks" into a stable source of points. If you need A-Level Physics tutoring, feel free to chat with our teachers.

Verification Note: This article was verified in September 2026: The assessment objective weightings for each Cambridge 9702 paper, the descriptions of AO1 and AO2, and the command words and their definitions are from Cambridge International's "Physics 9702 syllabus for 2025, 2026 and 2027"; the statement that all six Edexcel IAL Physics unit papers may include extended-writing questions, and the definitions of each command word in the command word table (Syllabus Appendix 9), are from the Pearson IAL Physics Syllabus (3rd Edition). The key points for explaining the photoelectric effect are based on the Cambridge syllabus requirements (verified in Article 177 on this site). The classification of question types, writing approaches, and common reasons for losing marks are our empirical suggestions.

References:

• Cambridge International: Physics 9702 Syllabus 2025–2027 (PDF)
• Pearson Edexcel: International A Level Physics Specification (PDF)