Describe four properties that all electromagnetic waves share.

AQA GCSE Physics (8463) — 4.6.2 Electromagnetic waves · Describe · 4 marks · View as Markdown

Written & reviewed by James Millett — Biology (Imperial College London), PGCE Science (University of Cambridge).

Model answer (4 marks)

1. They are transverse waves.
2. They travel at the same speed in a vacuum (c≈3.0×10^8 m s^−1).
3. They transfer energy from a source to an absorber.
4. They do not require a medium and can propagate through a vacuum.

Examiner tips

Use the exact wording from the mark scheme (e.g. ‘transverse waves’, ‘same speed in a vacuum’).
List the four properties in separate points to show clear structure.
Mention the speed value (c≈3.0×10^8 m s^−1) to demonstrate knowledge of the constant.

Common mistakes

Confusing electromagnetic waves with mechanical waves and saying they need a medium.
Omitting the speed value or not specifying that it is in a vacuum.
Using vague terms like ‘fast’ instead of the exact speed.”

Mark scheme (4 marks)

All electromagnetic waves are transverse waves
All electromagnetic waves travel at the same speed in a vacuum / in space
Electromagnetic waves transfer energy from a source to an absorber
Electromagnetic waves do not require a medium / can travel through a vacuum

Key terms in this question

electromagnetic waves