# Infrared radiation, microwaves and radio waves are all found in the electromagnetic spectrum. A student claims that these three types of radiation are fundamentally the same kind of wave. Justify the student's claim, and state the correct order of these three types of radiation from lowest frequency to highest frequency.

> Eduqas GCSE Physics — 6.1 Frequency range of the spectrum · Justify · 4 marks

## Mark scheme (4 marks)

1. All electromagnetic waves are transverse waves
2. All electromagnetic waves travel at the same speed in a vacuum / the speed of light (3 × 10⁸ m/s)
3. Radio waves have the lowest frequency of the three
4. Correct full order: radio waves → microwaves → infrared (lowest to highest frequency)

## Key terms

- [electromagnetic spectrum](https://www.gradenine.co.uk/glossary/electromagnetic-spectrum)
- [frequency](https://www.gradenine.co.uk/glossary/frequency)

## Related

- [Revision notes for Eduqas GCSE Physics](https://www.gradenine.co.uk/learn)
- [How to answer "Justify" questions](https://www.gradenine.co.uk/tools/command-word-cheatsheet)
- [Practice this with AI marking (free)](https://www.gradenine.co.uk/start)

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Source: [GradeNine](https://www.gradenine.co.uk/q/infrared-radiation-microwaves-and-radio-waves-5239bb3a) · Published by Druglandscape Ltd.