# A security scanner at an airport uses X-rays to image the contents of passengers' luggage. A passenger asks why X-rays are used rather than radio waves, which are also electromagnetic waves. Explain why X-rays are suitable for this purpose and describe the health risk associated with repeated exposure to X-rays for the airport security staff who operate the scanner.

> Edexcel A-Level Physics (9PH0) — 5.2 Quantum physics · Explain · 5 marks

> Airport security scanners transmit electromagnetic radiation through luggage to produce an image of the contents inside.

## Mark scheme (5 marks)

1. X-rays can pass through/penetrate materials (such as luggage/soft materials) to reveal internal structure
2. Radio waves are not suitable because they do not penetrate / interact with the contents in the same way OR radio waves have too long a wavelength / too low a frequency to image small objects inside luggage
3. X-rays transfer energy to cells in the body (because they have high frequency / high energy)
4. This can cause mutation of cells / damage to cells
5. Repeated / prolonged exposure increases the risk of cancer

## Key terms

- [X-rays](https://www.gradenine.co.uk/glossary/x-rays)
- [electromagnetic waves](https://www.gradenine.co.uk/glossary/electromagnetic-waves)

## Related

- [Revision notes for Edexcel A-Level Physics (9PH0)](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-security-scanner-at-an-airport-901589db) · Published by Druglandscape Ltd.