IGCSE Physics: Radiation | Edexcel Modular | Unit 3 | L5

IGCSE Physics: Radiation | Edexcel Modular | Unit 3 | L5

This lesson covers spec points 3.6 and 3.8 — describing how thermal energy is
transferred by infrared radiation, and explaining how emission and absorption
are related to surface colour and texture.

PowerPoint includes:
• Retrieval starter reviewing conduction and convection from L3–L4
• Direct Instruction (I Do) — infrared radiation defined; key point that
radiation requires no medium introduced; emission and absorption linked to
surface colour and texture; matt black as best emitter and absorber; shiny
silver as worst; NB note clarifying the EM spectrum is Unit 5 content;
Qatar-relevant applications introduced (solar water heaters, house colour)
• Guided Practice (We Do) — surface and cooling investigation: two beakers
wrapped in matt black paper and silver foil, filled with hot water; students
record temperature every minute for 10 minutes using a provided results table
• Independent Practice (You Do) — activity sheet with pre-filled investigation
data for classes that cannot run the practical
• Review and Reflect — MCQs and exit ticket

Activity Sheet includes:
• Pre-filled results table from the surface colour and cooling investigation
(allows the sheet to be used independently if the practical cannot be run)
• 9 exam-style questions plus stretch, progressing from recall through
explanation to real-life contexts including solar heaters in Qatar,
survival blankets and the Sun’s energy reaching Earth through a vacuum
• Full mark scheme for teacher use