Center of Mass

Overview

This lesson should keep the practical data and the balancing model tied together throughout.

Key knowledge and explanations

• Core practical focus: Investigate the relationship between distance and force and use it to determine the weight of a ruler.
• Identify the variables, method steps, and data that matter.
• Note the equipment, safety points, and precision issues to emphasise.

Lesson flow

1. Review the question, method, and success criteria for the practical work.
2. Set up equipment and model any critical measurements or safety points.
3. Collect results, observations, or graphs with checks on accuracy and control variables.
4. Review conclusions, anomalies, and how the method could be improved.

Checks for understanding

• Check that students can justify the method and identify variables.
• Use one question on results, anomalies, or evaluation to test understanding.

Common mistakes or misconceptions

• Missing control variables, weak measurement technique, or poor recording of data.
• Safety, setup, or graphing errors that need modelling before students continue.

Follow-up

• Complete the write-up, analysis, or evaluation.
• Revisit the method or results in the next lesson if improvement is needed.