IB MYP Integrated Sciences e-Assessment : Magnetism and magnetic fields Exam Style Practice Questions - New Syllabus
Question (15 marks)
Topic: Change (Energy Technology)
This question evaluates the replacement of incandescent bulbs with LED bulbs from multiple perspectives.
Question a (1 mark)
Topic: Fuels (Combustion)
Identify one safety concern with using candles/oil lamps for lighting.
▶️Answer/Explanation
Answer:
Fire risk or inhalation of smoke/CO2
Explanation:
Open flames pose continuous fire hazards, while incomplete combustion can produce dangerous gases – problems solved by electric lighting.
Question b (14 marks)
Topic: Fuels (Environmental Implications)
Evaluate replacing incandescent bulbs with LEDs using the infographic data:
| Feature | Incandescent | LED |
|---|---|---|
| Lifetime | 1,000 hours | 25,000 hours |
| Cost per bulb | $0.50 | $10.00 |
| 25,000 hr cost | $177.50 | $36.13 |
| Efficiency | 15% | 45% |
| Recyclability | Difficult | Unknown (new tech) |
▶️Answer/Explanation
Addressing Electricity Demand (4 marks)
Level 4 Response:
• LEDs use 70% less energy (45% vs 15% efficiency)
• Reduce power plant demands
• Longer lifespan decreases production frequency
Explanation: LEDs directly reduce electricity consumption through superior energy conversion.
Environmental Advantages (3 marks)
Level 4 Response:
• Pro: Lower CO2 emissions from reduced energy use
• Con: Unknown recycling potential may create future e-waste
Explanation: While clearly better operationally, the new technology may have undisposed environmental costs.
Economic Impacts (4 marks)
Level 4 Response:
• Initial: Higher unit cost ($10 vs $0.50)
• Long-term: Saves $141.37 over 25,000 hours
• Payback period: ~1,000 hours of use
Explanation: Despite higher upfront cost, LEDs offer substantial savings through reduced replacement and energy costs.
Conclusion (3 marks)
Level 4 Response:
“LEDs should replace incandescents because their energy savings and long-term cost benefits outweigh initial expenses, despite some uncertainty about recycling. This change supports sustainable development goals by reducing resource use and emissions.”
Explanation: Balanced conclusion that references multiple evaluation criteria and supports the transition.
Syllabus Connections:
- Energy Transfer: Efficiency comparisons (15% vs 45%)
- Environmental Implications: Lifecycle analysis of technologies
- Economic Factors: Cost-benefit analysis of energy choices