Or, “What happens when you interpret riddles literally?”.
“Physion is a 2D Physics simulation software. It can be used to easily create a wide range of interactive physics simulations and educational experiments. Teachers may find it particularly useful since it can be used as a virtual physics laboratory through which they can demonstrate some basic physics concepts in the classroom.
“The user, using the tools of Physion, can create various physical objects (circles, polygons, gears, etc.) and joints (eg. springs, pulleys etc.) that obey the laws of Physics. This way the user can experiment by creating various scenes/scenarios which can be either simple physics experiments or complex structures/mechanisms…
“Physion has been translated into the following languages: English, Greek, Russian, Japanese, German, Spanish and Indonesian. The software is available both for Windows (XP, Vista, 7) and Linux (x86 and x86_64) operating systems and most importantly it is 100% free.”
Hyperphysics is an extensive resource for many subfields of physics. Topics usually include a brief introduction and thorough description, the basic relevant formulas, and links to related topics.