electromagnetism

electromagnetism

1. this is a spectrum of radiation which are ordered in wavelengths

2. there are many in the specturm

   • shortest wavelength- 1. gamma rdiation - this is used to sterilise medical equipment and can only be stopped by a few inches of lead or a few metres of concrete
     • 2. x-ray this type of radiatiion doesnt pass through metals and bone so is used for medical imaging
       • 3.ultraviolet radiation - this is absorbed bythe skin and makes it turn darker it is used in tanning bed and is absorbed by the coationg on the bulbs and re-emitted as visible light
         • 4. visible light - this is all the light you can see violet has the shortest wavelength and red has the longest
           • 5. infrared radiation - this is felt on the skin as heat and is used in toasters and tv remotes it is also an invisible type of radiation
             • 6. microwaves - these are used in microwave ovens and for phone signals the radiation is absorbed by water in food and heats it up this is how microwave ovens work this is also an invisible type of radiation
               • longest wavelength - radio waves are used to transmit telephone and radio programmes some types of radio waves are diffrected by the ground so can be recived behind hills and some off of a layer of the atmosphere called the ionosphere so can be sennt around the world