Internal Assessment Guide
IA Purpose and Assessment Criteria · Choosing a Research Question · Worked Example Investigation Outline · Common Pitfalls
IB Physics SL topic guide
Internal Assessment
Internal Assessment is a core part of IB Physics SL. This guide connects the syllabus ideas behind Internal Assessment Guide, shows how they appear in worked problems, and points you to the formulas and full lessons needed for exam revision.
What you will learn
Internal Assessment syllabus outline
The units below follow the structure used in the full Study to Learn course. Use the outline to identify exactly which idea needs attention, then work through the public example before continuing to the complete lesson path.
Free worked preview
IA Purpose and Assessment Criteria
This complete preview comes from the Internal Assessment Guide unit. It introduces the core language, shows the method in context, and gives you a real example of the lesson quality before you create an account.
What Is the Physics IA?
The Internal Assessment is your opportunity to be a real physicist — to design, execute, analyse, and critique your own experiment on a topic that genuinely interests you. Worth 20% of your final grade, the IA rewards personal engagement and critical thinking more than getting a "right" answer. This guide walks you through the five assessment criteria (Personal Engagement, Exploration, Analysis, Evaluation, and Communication), explaining what each actually rewards and how to avoid the most common pitfalls. By the end of this lesson you will understand the marking framework well enough to self-assess your own report before submission.
The Internal Assessment is an individual scientific investigation into a testable research question. You design and carry out your own experiment, collect and analyse data, and write a report of 6–12 pages. The IA is worth 20% of your final IB Physics grade and gives you the chance to explore a topic you are genuinely interested in.
Timeline Overview
Most schools allocate roughly 10 hours of class time for the IA, spread across planning, data collection, and writing. Your teacher provides guidance during the planning stage but you must carry out the experiment and write the report independently.
The Five Assessment Criteria
Personal Engagement (2 marks)
This criterion rewards evidence of genuine personal interest and initiative — for example, designing a piece of your own apparatus, choosing a research question connected to a personal hobby or curiosity, or showing independent thinking in how you adapted the investigation.
Exploration (6 marks)
A strong exploration includes: a focused, clearly stated research question with identified independent and dependent variables; relevant background physics explained in your own words; a well-described methodology; and appropriate consideration of safety and ethical issues.
Analysis (6 marks)
This criterion evaluates how you process and present your raw data. You need to show you can: record data with appropriate precision; calculate averages and uncertainties correctly; choose the right type of graph to test your hypothesis; include error bars where relevant; and interpret what the graph's gradient, intercept, or shape tells you about the physics relationship.
Evaluation (6 marks)
A strong evaluation: identifies specific, genuine limitations in your method or equipment; explains how each limitation might have affected your results; and proposes realistic, specific improvements. Comparing your result to an accepted literature value and calculating a percentage error is expected where possible.
Communication (4 marks)
This assesses the overall quality of your report as a scientific document. It must be well-structured with clear section headings, written in a formal scientific style, and include properly formatted references and citations.
ImportantThe five criteria are assessed independently — doing brilliantly on analysis does not compensate for a weak evaluation.
Reviewed by the Study to Learn editorial team · Updated 2026-07-24