What Are Electromagnetic Waves and How Are They Used in Radio and Radar?

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Electromagnetic waves are produced by the oscillation of electric and magnetic fields, which occur when electric charges are accelerated. These waves travel at a speed of approximately 3.0 x 10^8 m/s, as derived from Maxwell's equations. Radio and radar systems utilize electromagnetic waves for communication and detection purposes, respectively. In these applications, electromagnetic waves transmit information by modulating their frequency or amplitude. Understanding the fundamental principles of electromagnetic waves is essential for exploring their applications in technology.
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just want to ask what are electromagnetic waves and how are they produced?
also, do you where i can get a simple application of EM waves? just really need it... thanks!
 
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When an electric field changes, it creates a magnetic field, and when the magnetic field changes, it creates an electric field. When you have a positive charge and a negative charge close together and you oscillate them, the electric field will create a magnetic field which will create an electric field which will create a magnetic field, and so on. This is an electromagnetic wave, an oscillation in the electric and magnetic fields. By rearranging Maxwell's equations it can be shown that electromagnetic waves travel at 3.0 * 10^8 m/s. There are a bunch of details I'm missing here, such as how electromagnetic waves fit in with quantum mechanics.
 
do radio and radar considered as applications of electromagnetic waves? if then, how do electromagnetic waves function in those applications?
 

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