There are many articles in the WWW about guitar pickups, which trying to show you how this stuff works. Many of them duplicate popular myths. Not a lot of them showing a good, technical analysis.
Here, I would like to present three good articles, abut technical character of guitar pickups. They all have some portion of physics and some practical music knowledge. This articles are more for those of you, who already know, why electric guitars have electromagnetic pickups, but want more technical, scientific knowledge.
Pickupology by Bill Lawrence
The Secrets of Electric Guitar Pickups by Helmuth E. W. Lemme
Some Words About Pickups by Sven Petersen
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