Lesson Plan

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Lesson Plan
Grade: Date: 17/01/2026
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:
  1. Do‑now (5'): Quick quiz on conduction & convection concepts (paper).
  2. Mini‑lecture (10'): Explain thermal radiation, photons, and why a vacuum is sufficient; introduce the Stefan‑Boltzmann law.
  3. Demonstration (10'): Use an infrared lamp to heat black paper vs. shiny foil; discuss emissivity and surface‑area effects.
  4. Guided practice (12'): Students calculate radiated power for a black‑body sphere (using given formula) in pairs.
  5. Group discussion (8'): Identify everyday examples, address misconceptions listed in the notes.
  6. Quick check (5'): Students answer the three “Quick Check Questions” on worksheets; peer‑review.
  7. 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.