They are about 100 000 times longer than visible light waves. They can range from the length of a football to longer than a football field.
Radio waves are produced by:
- Acceleration of electrons
- Planets and comets
- Stars and galaxies
- Clouds of gas and dust
Radio waves is used to:
- Transfer signal to
- radios
- television
- cell phones
- Observe space
The advantage of radio wave telescopes is that they are not affected by sunlight, clouds and rain.
The disadvantage of them is that they have to cover a large area to be able to obtain a clear picture.
Large doses of radio waves are believed to cause cancer, leukaemia and other disorders.
Some people claim that the very low frequency field from overhead power cables near their homes has affected their health.
Simulator:
PhET: http://phet.colorado.edu/en/simulation/radio-waves
How do you make a radio wave?: http://www.qrg.northwestern.edu/projects/vss/docs/communications/3-how-do-you-make-a-radio-wave.html
Sources:
Netting, R. (2007). Radio waves. Retrieved July 7, 2011, from: http://science.hq.nasa.gov/kids/imagers/ems/radio.html
Amazing Space. (n.d.). Definition: radio waves. Retrieved July 7, 2011, from: http://amazing-space.stsci.edu/resources/explorations/groundup/lesson/glossary/term-full.php?t=radio_waves
Wolfs, F. (n.d.). Light and radio waves. Retrieved July 7, 2011, from: http://teacher.pas.rochester.edu/phy122/Lecture_Notes/Chapter36/chapter36.html
Electromagnetic Spectrum. (n.d.). The electromagnetic spectrum: radio waves. Retrieved July 7, 2011, from: http://www.darvill.clara.net/
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