X-Rays
Physics: AQA GCSE Higher, topic 6.4.3
X-rays
X-rays carry the second most energy of all the waves in the electromagnetic spectrum.
Uses
- Low-energy X-rays are used for medical and industrial imaging.
- High-energy X-rays are used to treat cancer.
- X-rays are also used for security purposes to detect weapons in airports (and other places).
Risks
- X-rays are highly ionising (can damage body cells), even in low doses.
Safety precautions
- Due to the dangerous nature of X-rays, exposure to X-rays should always be kept to a minimum.
- People working with X-ray equipment should always shield themselves to prevent exposure to X-rays.
- These people will place materials (metals like lead) between themselves and the X-rays.
Explanation
- X-rays penetrate soft materials (like body tissue).
- Bones are dense materials that absorb X-rays. We can use X-rays to build a shaded image of bones and body tissue.
Test yourself on X-Rays
Which one of these is a use of low-energy X-rays?
Dentists often take X-ray images of a patient's teeth. The dentist operates the X-ray machine from behind a wall. Why does the dentist take this precaution when it is the patient who receives the dose of X-ray radiation?