Radio waves are just another form of light and travel at the same speed: 186,000 miles per second. Radio waves can get to the moon and back in 21⁄2 seconds or circle the Earth in 1⁄7 of a second.
An electric field and a magnetic field carry the energy of a radio wave.
These fields affect charged particles, such as the electrons in a wire, and make them move. Electrons move in specific ways: They move parallel to electric fields and in circular motions in response to magnetic fields. These moving electrons (that is, current) also create moving electric and magnetic fields.
Transmitters cause electrons to move so that they, in turn, create the moving
fields of radio waves. Antennas are just structures for electrons to move in to
create radio waves. The electrons in an antenna also move in response to
radio waves launched by other antennas. Receivers then detect the electron
motion caused by the incoming radio waves. The energy is just transferred
from electrons to radio waves and back to electrons at the other station.
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