Illustrations that I have added to Wikimedia Commons and inserted in some articles:
Illustration of the electric field surrounding a positive (red) and a negative (green) charge (click for larger image). I inserted this illustration in the Electric field article.
Illustration of the electric field surrounding two equal charges (click for larger image).
Illustration of the electric field surrounding one positive charge (click for larger image). I'm not quite satisfied with this one, but I don't see any article where it would be obvious to use, so I won't improve it just now.
Wikipedia:Did you know... is a section you can see on the Main Page. It showcases new or recently expanded articles that are selected through an informal review process. It is not a general trivia section.
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Beginners should consult this Did You Know glossary if they don't understand any of the terms used. Beginners may like to start by looking at a summary of our many rules: this provides links to pages with more detailed explanations (which in turn may link to even more detailed pages).