Physics IA Data Analysis and Evaluation

Act as an IB Physics IA examiner. Help me analyze data and evaluate my Physics IA: **DATA PROCESSING:** 1. **Raw Data Table**: Organize with clear headers including units and uncertainties - Example: Length $l$ / m (±0.001) 2. **Processed Data**: Show ALL calculations for at least one data point - Calculate averages from trials - Propagate uncertainties using: - Addition/subtraction: $$\Delta z = \Delta x + \Delta y$$ - Multiplication/division: $$\frac{\Delta z}{z} = \frac{\Delta x}{x} + \frac{\Delta y}{y}$$ - Powers: $$\frac{\Delta z}{z} = n \cdot \frac{\Delta x}{x}$$ 3. **Graphing**: - Plot processed data with error bars - Draw line of best fit AND max/min gradient lines - Calculate gradient with uncertainty: $$m = \frac{\Delta y}{\Delta x}$$ - Linearize if needed (e.g., plot $T^2$ vs $l$ for pendulum) 4. **Percentage Error**: Compare experimental value to literature value $$\text{\% error} = \frac{|\text{experimental} - \text{accepted}|}{\text{accepted}} \times 100\%$$ 5. **Percentage Uncertainty**: Calculate for your key result $$\text{\% uncertainty} = \frac{\text{absolute uncertainty}}{\text{measured value}} \times 100\%$$ **EVALUATION:** 6. **Strengths**: What worked well in your methodology? 7. **Systematic Errors**: Identify errors that consistently push results in ONE direction 8. **Random Errors**: Identify sources of scatter in your data 9. **Compare % error to % uncertainty**: If % error > % uncertainty, systematic errors dominate 10. **Improvements**: Suggest SPECIFIC, REALISTIC improvements (not just "use better equipment") 11. **Extensions**: How could this investigation be taken further? **Common Mistakes:** - Forgetting error bars on graphs - Not showing sample calculations for processed data - Listing improvements that don't address identified weaknesses - Confusing systematic and random errors **IB Tip:** The evaluation is worth 25% — don't rush it. Link every weakness to a specific improvement. **My raw data and experiment:** [PASTE YOUR RAW DATA OR DESCRIBE YOUR RESULTS]