# A doctor uses gamma rays to treat a patient's cancer. After the treatment, the patient asks why gamma rays were chosen instead of radio waves to target and destroy the cancer cells. Explain why gamma rays are more suitable than radio waves for destroying cancer cells, and describe one risk to healthy cells from using gamma rays.

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

> Gamma rays and radio waves are both part of the electromagnetic spectrum. Gamma rays have the highest frequency in the electromagnetic spectrum, whilst radio waves have the lowest.

## Mark scheme (5 marks)

1. Gamma rays have a higher frequency than radio waves
2. Higher frequency means gamma rays carry more energy (per wave/photon)
3. The greater energy of gamma rays can cause mutations or damage to cancer cells / sufficient energy to destroy cancer cells
4. Radio waves do not carry enough energy to damage or destroy cells (so would be ineffective)
5. Gamma rays can cause mutation or damage to healthy/surrounding cells, which could cause cancer in those cells

## Key terms

- [gamma rays](https://www.gradenine.co.uk/glossary/gamma-rays)

## 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-doctor-uses-gamma-rays-to-51cca533) · Published by Druglandscape Ltd.