Albert Einstein, asked to describe radio: "You see, wire telegraph is a kind of a very, very long cat. You pull his tail in New York and his head is meowing in Los Angeles. Do you understand this? And radio operates exactly the same way: you send signals here, they receive them there. The only difference is that there is no cat."
For me, I will give an example. I will start my sports car outside using my remote car starter. My car starts because of the signal. That signal is a radio wave. Similarly, the signal on your wifi, phones, TV, radio (AM and FM) are radio waves. If we look at it, in reality, waves are everywhere but we cannot see it.
Dear R. Mocana,
Your idea of explaining radio waves in this kind of manner is intriguing so I made a further step in order to make it more simpler and have a little fun with it. Please be free to make the idea of explaining radio waves even simpler and add probably a newer and more funnier theory of operation. My explanation follows:
Radio Wave is a type of team players. E.g. Some teams have 10 players, or 100 players or an enormous number of players. If each player conducts exactly the same movement then the this team (signal) is named as a periodic team which has e.g. 10 players (periods). If a team has aeroplanes, then this team does not need a surface (wired communications) in order their players to move but on the contrary its players are the aeroplanes which they fly on the air (wirelessly transmitted radio waves). These aeroplanes are invisible.
A time-varying electric field creates
a time-varying magnetic field which creates
a time-varying electric field which creates ...
This can happen in a sealed metal container such as a cube or a cylinder, and then we call these standing (stationary) waves.
If there is incomplete confinement then traveling waves are formed.
I would define an "explanation" ad describing something that you do not understand in terms of something that you think you understand. Analogies of radio waves to ripples on water is misleading because you could ask what is the medium (the water) and be led to believe in an ether. That is why it may be better to explain radio waves in terms of the energy being in two different states, an electric field and a magnetic field, and alternating from one to the other as I did at the beginning.
Mark
I like to think about what is happening along an antenna in order to produce or receive a radio wave in the first place. An electric circuit is used to oscillate electrons at a frequency; pushing and pulling electrons up and down the antenna causing the electric fields and induced magnetic fields to oscillate as well causing a wave in the electrons in free space, which travel away as a radio wave. We all know radio waves can have different frequencies, which is equal to the frequency that the electrons are being pushed and pulled along the antenna.
Albert Einstein, asked to describe radio: "You see, wire telegraph is a kind of a very, very long cat. You pull his tail in New York and his head is meowing in Los Angeles. Do you understand this? And radio operates exactly the same way: you send signals here, they receive them there. The only difference is that there is no cat."
Here it is my attempt to stay in between the simple and complex:
Imagine a pair of magnets. Everybody knows that, when one is neared to the other, magnets either strongly repel or attract each other and this effect can be switched by rotating one of the two magnets. Now imagine to pin the two magnets on a table through a needle in their center, close enough to each other but without allowing them to come in touch. When one extremity of one of the magnets is neared to the other one, this will rotate to align with its pair. If the first magnet is reversed, the second will quickly reverse too. Then, if the first magnet is put in steadyrotation, the second one will also start rotating even though no one is directly pushing it! That is because the rotating magnet is generating an alternating force that is transmitted to the second magnet through the space. That is exactly a radio wave: an alternating force propagating through space that transmits energy without transmission of any material. (To be a bit more precise, radio waves are only those waves generated by an electromagnetic source, like our magnet or an electric charge. Other waves are known, like gravitational waves generated by the movement of masses, e.g. planets).
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