Lesson Plan

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Lesson Plan
Grade: Date: 25/02/2026
Subject: Physics
Lesson Topic: Describe the effect of surface colour (black or white) and texture (dull or shiny) on the emission, absorption and reflection of infrared radiation
Learning Objective/s:
  • Describe how colour (black or white) influences the emission, absorption and reflection of infrared radiation.
  • Explain how surface texture (dull vs shiny) modifies infrared reflection and its impact on heat transfer.
  • Compare the combined effects of colour and texture for the four common surface types.
  • Apply the concepts to predict which materials will cool faster or are best for insulation or heat‑radiating applications.
Materials Needed:
  • Projector and laptop with presentation slides
  • Printed worksheet containing the colour‑texture table
  • Sample material pieces: black‑matte card, black‑shiny foil, white‑matte card, white‑shiny foil
  • Infrared thermometer or thermal camera
  • Whiteboard and markers
  • Exit‑ticket slips
 Introduction:

Begin with everyday examples – a black radiator heating a room and white roof tiles keeping a house cool – to hook interest. Ask students to recall what they know about infrared radiation, emissivity and reflectivity. State that by the end of the lesson they will be able to describe and predict how colour and texture affect infrared emission, absorption and reflection.
Lesson Structure:
  1. Do‑now (5'): Quick quiz on definitions of emission, absorption and reflection.
  2. Mini‑lecture (10'): Present colour and texture effects using diagrams and the summary table.
  3. Demonstration (10'): Use the IR thermometer on the four sample surfaces; students record temperature changes.
  4. Group activity (15'): Complete a comparative table of the four surface types and discuss findings.
  5. Concept check (5'): Think‑pair‑share answering the exam‑style question about cooling rates.
  6. Summary & exit ticket (5'): Students write one sentence explaining which plate cools faster and why; collect tickets.
Conclusion:

Recap the key relationships between colour, texture, emissivity and reflectivity, emphasizing the practical examples discussed. Collect the exit tickets to gauge understanding, and assign a short homework task: research a real‑world application (e.g., roofing paint, heat sinks) and explain how colour and texture are chosen for optimal infrared behaviour.