Electromagnetic spectrum
Cambridge A-Level Physics (9702) · Unit 7: Waves · 6 flashcards
Electromagnetic spectrum is topic 7.4 in the Cambridge A-Level Physics (9702) syllabus , positioned in Unit 7 — Waves , alongside Progressive waves, Transverse and longitudinal waves and Doppler effect for sound waves. In one line: All electromagnetic waves are transverse waves. This means that the oscillations are perpendicular to the direction of energy transfer.
Marked as AS Level: examined at AS Level in Paper 1 (Multiple Choice), Paper 2 (AS Structured Questions) and Paper 3 (Advanced Practical Skills). The same content may also be assumed in Paper 4 (A Level Structured Questions).
The deck below contains 6 flashcards — 3 definitions and 3 key concepts — covering the precise wording mark schemes reward. Use the 3 definition cards to lock down command-word answers (define, state), then move on to the concept and calculation cards to handle explain, describe, calculate and compare questions.
What type of waves are all electromagnetic waves
All electromagnetic waves are transverse waves. This means that the oscillations are perpendicular to the direction of energy transfer.
What the Cambridge 9702 syllabus says
2025-2027 syllabus, in our words · AS LevelWhat the syllabus expects you to be able to do in this topic, in plain English. For the exact wording, see the official syllabus (PDF).
- State that every electromagnetic wave is transverse and that, in free space, they all travel at the same speed c.
- Recall approximately what range of free-space wavelengths each main region of the electromagnetic spectrum covers, for every region between γ-rays and radio waves.
- Recall that the human eye can see free-space wavelengths between 400 nm and 700 nm.
Cambridge syllabus keywords to use in your answers
These are the official Cambridge 9702 terms tagged to this section. Mark schemes credit responses that use the exact term — weave them into your answers verbatim rather than paraphrasing.
What type of waves are all electromagnetic waves?
All electromagnetic waves are transverse waves. This means that the oscillations are perpendicular to the direction of energy transfer.
What is the speed of all electromagnetic waves in free space?
All electromagnetic waves travel at the same speed in free space, denoted as 'c'. The value of c is approximately 3.0 x 10^8 m/s.
List the principal regions of the electromagnetic spectrum in order of decreasing wavelength.
Radio waves, microwaves, infrared, visible light, ultraviolet, X-rays, gamma rays. Remember: Radio waves have the longest wavelength and gamma rays have the shortest.
What is the approximate range of wavelengths, in nanometers, that are visible to the human eye?
The approximate range of wavelengths visible to the human eye is 400-700 nm. This corresponds to the colors of the visible light spectrum.
Which region of the electromagnetic spectrum has wavelengths slightly longer than visible light?
Infrared radiation has wavelengths slightly longer than visible light. Infrared is often associated with heat.
Which region of the electromagnetic spectrum has wavelengths slightly shorter than visible light?
Ultraviolet radiation has wavelengths slightly shorter than visible light. Ultraviolet radiation can be harmful to living tissues.
Review the material
Read full revision notes on Electromagnetic spectrum — definitions, equations, common mistakes, and exam tips.
Read NotesMore topics in Unit 7 — Waves
Electromagnetic spectrum sits alongside these A-Level Physics decks in the same syllabus unit. Each uses the same spaced-repetition system, so progress in one informs the next.
Key terms covered in this Electromagnetic spectrum deck
Every term below is defined in the flashcards above. Use the list as a quick recall test before your exam — if you can't define one of these in your own words, flip back to that card.
How to study this Electromagnetic spectrum deck
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