Medical Physics

What the resources cover

Most of this unit is made up of mind maps. They work through the main medical uses of physics: X-rays, ultrasound, CT scans, fluoroscopy, ECGs and medical tracers. The map on X-rays describes them as part of the electromagnetic spectrum, with high frequency and a very short wavelength, close to the diameter of an atom. Other maps note that X-rays are absorbed by bone and metal but transmitted by soft, healthy tissue.

Where to start

Begin with the Ultrasound mind map. It explains that the human ear detects sound between 2Hz and 20,000Hz, and that higher frequencies are called ultrasound. Then open the X-rays mind map to see the properties and uses side by side.

For a wider view, try these:

• The Physics In Medicine mind map, which links X-rays, CT scans, ultrasound, lenses, the eye and endoscopes.
• The Medical Uses mind map, which adds pacemakers, cyclotrons, electrocardiographs and ionising and non-ionising radiation.
• The Diagnosis Methods in Medicine mind map, which covers medical tracers and technetium-99m as a gamma emitter used for imaging.

Using quizzes and maps together

Read a map first, then test yourself. The quiz AQA GCSE Physics Unit 3.1 asks questions such as what a charge-coupled device does in X-ray imaging and why barium meals are used as a contrast medium. Check any wrong answers against the matching map, then retry the quiz.

If you prefer short prompts, the A2 Physics Medical Imaging flashcard deck goes further. It covers the production of X-rays, tube current, intensity, hardness, the X-ray spectrum and how to reduce the radiation dose.

Where it fits

This unit sits in the Atomic, Nuclear and Modern Physics strand of Physics. Many resources are labelled with exam-board topic names, so check the title to match your course.

When you're ready, pick one map, work through a quiz on it and see what you can recall.