Bitesize has changed! We're updating subjects as fast as we can. Visit our new site to find Bitesize guides and clips - and tell us what you think!
Print

Science

Cooking and communication using waves

Page:

  1. 1
  2. 2
  3. 3
  4. 4
  1. Next

Infrared radiation and microwaves can be used to cook food. Microwaves are also used to transmit information, such as mobile phone networks.

Cooking with infrared

All objects give out and take in infrared radiation. The hotter an object is, the more infrared radiation it emits.

Very hot objects may glow, such as the heating element in a toaster or an electric fire. Other hot objects may not glow, such as an iron.

Some surfaces are better than others at emitting and absorbing infrared radiation:

surfaces that emit and absorb radiation

colourtextureability to emit infrared radiationability to absorb infrared radiation
blackdullgoodgood
whiteshinypoorpoor

Shiny surfaces reflect infrared radiation.

When an object absorbs infrared radiation, its temperature increases. Food, for instance, begins to cook when its surface absorbs infrared radiation.

Page:

  1. 1
  2. 2
  3. 3
  4. 4
  1. Next

Back to Energy for the home index

BBC © 2014 The BBC is not responsible for the content of external sites. Read more.

This page is best viewed in an up-to-date web browser with style sheets (CSS) enabled. While you will be able to view the content of this page in your current browser, you will not be able to get the full visual experience. Please consider upgrading your browser software or enabling style sheets (CSS) if you are able to do so.