| Lesson Plan |
| Grade: |
Date: 04/03/2026 |
| Subject: Physics |
| Lesson Topic: Know that thermal energy transfer by thermal radiation does not require a medium |
Learning Objective/s:
- Describe how thermal radiation transfers energy via electromagnetic waves.
- Explain why a material medium is not required for radiation and contrast it with conduction and convection.
- Apply the Stefan‑Boltzmann law to calculate the power radiated by objects of different temperatures, areas and emissivities.
- Identify real‑world examples of thermal radiation and correct common misconceptions.
|
Materials Needed:
- Projector and screen
- PowerPoint/slide deck on thermal radiation
- Infrared heat lamp
- Black matte paper and shiny aluminium foil (to compare emissivity)
- Thermometer or IR temperature sensor
- Student worksheets with practice problems
- Calculators
- Exit‑ticket slips
|
Introduction:
Begin with the question “How does the Sun’s heat reach Earth?” to spark curiosity. Review students’ prior knowledge of conduction and convection, highlighting that those modes need a material. State that by the end of the lesson they will be able to explain why radiation works without a medium and demonstrate its calculation.
|
Lesson Structure:
- Do‑now (5'): Quick quiz on conduction & convection concepts (paper).
- Mini‑lecture (10'): Explain thermal radiation, photons, and why a vacuum is sufficient; introduce the Stefan‑Boltzmann law.
- Demonstration (10'): Use an infrared lamp to heat black paper vs. shiny foil; discuss emissivity and surface‑area effects.
- Guided practice (12'): Students calculate radiated power for a black‑body sphere (using given formula) in pairs.
- Group discussion (8'): Identify everyday examples, address misconceptions listed in the notes.
- Quick check (5'): Students answer the three “Quick Check Questions” on worksheets; peer‑review.
- Exit ticket (5'): Write one key fact about thermal radiation and one question they still have.
|
Conclusion:
Summarise that thermal radiation transfers energy via electromagnetic waves and does not need a material medium, reinforcing the Stefan‑Boltzmann relationship. Collect exit tickets as a retrieval check and assign a homework task to calculate the radiative heat loss of a household window at night.
|