how about http://www.phy.ntnu.edu.tw/ntnujava/index.php?board=21.0
you can download the XMl

explore it

change it to see what happens

are you trying to make physics applets or others.

physics here has plenty,

others u can try posting questions here http://www.phy.ntnu.edu.tw/ntnujava/index.php?board=23.0

build a database of "how to do this in Ejs" for others to do a search in the forum