IB DP Physics Determining Refractive Index Pre-Lab Notes 2026

Physics Determining Refractive Index Using Snell’s Law: Pre-Lab Notes and Practical Guide

This pre-lab resource prepares students for an investigation of the refractive index of materials using Snell’s Law. It provides a structured introduction to the physics concepts, measurement techniques, and practical considerations before students begin laboratory work.

Keeping it Simple
This pre-lab pack offers a clear, accessible overview of refraction and refractive index concepts without dense theory. It focuses on the essential ideas and practical steps that students need before entering the lab, helping build confidence with apparatus setup, data collection, and analysis.

What’s Included in This Pre-Lab Pack

1. Student Pre-Lab Notes – A clearly structured preparation guide with:
   • Simple explanations of refraction, refractive index, and Snell’s Law
   • Diagrams showing typical apparatus such as ray box, protractor, and block
   • Step-by-step outline of experimental procedure for measuring incident and refracted angles
   • Guidance on calculating refractive index from measured angles
   • Worked examples showing how to use Snell’s Law in calculations
   • Safety notes on handling optical equipment and light sources
   • Exam tips addressing common misunderstandings about angle measurement and uncertainty

2. Teacher Notes – Support for pre-lab discussion:
   • Concise background theory linking refraction to refractive index
   • Suggestions for pre-lab questioning and concept checks
   • Common student challenges (accurate angle measurement, interpreting results)
   • Differentiation strategies for students with varied confidence in measurement and maths
   • Assessment opportunities tied to data analysis and conceptual reasoning

3. Technician Preparation Guide – Setup information:
   • Materials and equipment list including ray box/light source, glass/plastic block, protractors, paper and pins
   • Health and safety reminders for handling optical equipment
   • Guidance for preparing labelled stations and marking reference lines
   • Step-by-step apparatus setup instructions
   • Troubleshooting advice for inconsistent light paths, alignment issues or measurement error

Audio Summary for Enhanced Learning
• A podcast-style audio summary is included for students who prefer listening
• Explains refraction and Snell’s Law in accessible language
• Walks through setup and measurement techniques
• Highlights safety considerations and practical tips
• Useful as pre-lab preparation or revision support

Ideal For:
• Students preparing for mechanics and wave optics practicals
• Audio learners who benefit from spoken explanations
• Teachers planning structured pre-lab sessions
• Technicians needing clear setup and safety guidance

This resource supports practical physics preparation by emphasising clarity, safe practice, and the development of essential measurement and analysis skills.