I was reading about how accelerated cahrges radiate electromagnetic waves, and i found the most known application on it was the dipole antenna, which was by applying an alternating voltage signal the electrons accelerated inside the wires back and forth then they will radiate electromagnetic waves. My problem arises when i was reading about antenna in Serway textbook and he mentioned that "The source of this radiation is the continuous induction of an electric field by the time-varying magnetic field and the induction of a magnetic field by the time-varying electric field" by this I got two different explinations on how dipole antenna radiate electromagnetic waves. Which one of the two previous explanations is true ?!
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The second explanation is incorrect. The time varying magnetic field is the radiation or contains it. Besides, the time derivative of B is the same thing as the rotation of E.
my2cts
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The best-known application of EM radiation is thermal sources. Electrons are accelerated chaotically and emit photons mainly from infrared to visible light.
Antenna radiation is a special case of photon emission. The electrons periodically accelerated up and down on the surface of the antenna rod emit polarised photons. Their magnetic and electric field components move forwards in the same direction and are periodically converted into each other in the near field of the antenna. In this respect, you have misinterpreted what follows from the quote; there are not two interpretations of one process. It is the description of the periodic transition between the two states.
More about EM radiation, EM waves and photons see my answer here.
HolgerFiedler
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