Brainlag PlusWhat each part of the spectrum is used for and why, which parts are ionising, radiation dose, how radio waves are made, and the infrared practical.
Each wave, its job
What a wave is used for depends on what absorbs it, what it passes through, and how much energy it carries.
- Radio waves: television and radio broadcasting. They travel long distances and pass through walls.
- Microwaves: satellite communications (they cross the atmosphere easily) and cooking (water in food absorbs them).
- Infrared: grills, toasters and heaters, thermal imaging cameras (warmer things give out more), remote controls.
- Visible light: seeing, photography, signals in optical fibres.
- Ultraviolet: fluorescent lamps, sun beds, security marks that glow on banknotes.
- X-rays: images of bones (bone absorbs them, soft tissue does not) and airport luggage scanners.
- Gamma rays: sterilising medical instruments and food, and treating some cancers.
The rest of this lesson and its 11 practice questions are in Plus.
Screen 1 of 4, free to read.
- 11 exam-style questions, marked as you go, each with a worked solution
- Anything you get wrong is saved to your flashcards