# A radio station broadcasts signals using electromagnetic waves. Explain what is meant by the terms wavelength, frequency, and period for these waves, and state the relationship between wave speed, frequency, and wavelength.

> WJEC A-Level Physics (Wales) — 3.1 Wave properties · Explain · 5 marks

> Radio waves are a type of electromagnetic wave. All electromagnetic waves travel at the same speed in a vacuum.

## Mark scheme (5 marks)

1. Wavelength is the distance from one point on a wave to the next identical point (e.g. crest to crest or trough to trough)
2. Frequency is the number of complete waves (oscillations/cycles) passing a point per second
3. Period is the time taken for one complete wave (oscillation/cycle) to pass a point
4. Period is equal to 1 divided by frequency (or frequency is 1 divided by period)
5. Wave speed equals frequency multiplied by wavelength

## Key terms

- [wavelength](https://www.gradenine.co.uk/glossary/wavelength)
- [frequency](https://www.gradenine.co.uk/glossary/frequency)
- [period](https://www.gradenine.co.uk/glossary/period)
- [wave speed](https://www.gradenine.co.uk/glossary/wave-speed)

## Related

- [Revision notes for WJEC A-Level Physics (Wales)](https://www.gradenine.co.uk/learn)
- [How to answer "Explain" 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/a-radio-station-broadcasts-signals-using-ebc4fea0) · Published by Druglandscape Ltd.