Any good Physics Interactive Programs out there?

[derek.basler]

Does anyone know of a good physics interactive computer program to mess around with, and perhaps even learn something? maybe even a mathematics program as well would be cool. if you have any ideas, i'd appreciate you sharing!

[pantaz]

"Phun is a free game-like 2D physics sandbox" http://www.phunland.com/wiki/Home

[robphy]

http://vpython.org/
http://www.opensourcephysics.org/ (http://www.compadre.org/osp/)

http://www.falstad.com/mathphysics.html
http://www.phy.ntnu.edu.tw/ntnujava/
http://www.walter-fendt.de/ph14e/

http://www.cut-the-knot.org/

Microsoft Physics Illustrator for Tablet PC (http://www.microsoft.com/downloads/details.aspx?familyid=56347faf-a639-4f3b-9b87-1487fd4b5a53&displaylang=en)
http://www.crayonphysics.com/ (not free)

[physics girl phd]

PhET (http://phet.colorado.edu/simulations/index.php?cat=Featured_Sims) (Out of the University of Colorado Physics Education Research Group) is popular (I use it a lot with my classes)... but you probably really need some guidance to get the most out of them... look at the activities in conjunction with a text, or look at some of the activities teachers have posted.

I also like Phun (the 2-D physics emulator mentioned before)... but it has no guidance either for really getting to understand the concepts.