Radio waves and Microwaves
Radio waves are used to broadcast radio or television signals from transmitters, which are then converted into electrical signals with an aerial (which is made out of metal to absorb the radio waves) so you can hear and see them. When done so the aerial converts this wave into an electrical signal (because of the electromagnetic waves energy exciting particles in the aerial and causing them to oscillate/vibrate and thus create an electrical current) this electrical signal is an alternating current which has the same frequency as the radio wave. This electrical energy can again be converted through a loudspeaker into sound, or using a television into light. Also each radio station and television station is given a specific frequency to broadcast at so that when you tune your television or radio you get only one radio station not all of them.
We not only send information in radio waves we also use microwaves. They are both absorbed by very thick or dense objects, like hills. However some long wave radio signals can be diffracted around a hill and still reach us to be able to be heard. This only happens to longer wave radio waves that have wavelengths of
around 1000m because the wavelengths are more similar to the sizes of the hills. Therefore because of this even if you live somewhere where there is no line of sight to a radio station you can still receive long wave radio signals, but not microwaves because they cannot be diffracted by hills as their wavelengths are much smaller. Also it is helpful to remember that radio waves can be reflected off the ionosphere and be received in longer distances through that route.
Satellites are used to transmit information very quickly around the world, and they can be used to get information to very hard to reach areas like places that are very remote – the top of Mount Everest. It can also provide a large area of land with...
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