Lesson Plan

• Recall the approximate wavelength ranges for each region of the electromagnetic spectrum from radio waves to γ‑rays.
• Explain the relationship c = λ ν and how it links wavelength and frequency.
• Compare typical applications of the different electromagnetic regions.
• Interpret a logarithmic diagram of the electromagnetic spectrum and identify region boundaries.

• Projector and computer
• Printed handout with the EM‑spectrum table (blank cells for student fill‑in)
• Whiteboard and markers
• Clicker/online quiz tool for quick checks
• Calculator (optional)

Begin with the question, “What do a radio, a microwave oven, and an X‑ray machine have in common?” Students recall that all involve electromagnetic waves. Review the previously learned formula c = λ ν as the link between wavelength and frequency. State that by the end of the lesson they will be able to list the wavelength ranges for each region and explain why each region is useful.

1. Do‑now (5 minutes): Quick clicker quiz on c = λ ν and a few example calculations.
2. Mini‑lecture (10 minutes): Present the EM‑spectrum table and a logarithmic diagram, highlighting the wavelength and frequency limits.
3. Guided practice (12 minutes): Students complete the handout by filling in missing wavelength ranges and discuss the overlap between regions.
4. Application activity (10 minutes): In small groups, match each region to a real‑world technology (e.g., radio communication, infrared imaging, UV sterilisation, etc.) and justify the choice.
5. Check for understanding (8 minutes): Exit‑ticket – write the wavelength range for two regions of the student’s choice and one practical use for each.

Summarise the vast span of the electromagnetic spectrum and reinforce the c = λ ν relationship. Collect the exit tickets to gauge mastery and assign a short homework: research a modern technology that relies on a specific EM region and prepare a one‑minute explanation for the next class.