this simulation version has been replaced by Ejs Open Source Newton's Cradle Java Applet by Fu-Kwun & lookang http://www.phy.ntnu.edu.tw/ntnujava/index.php?topic=2195.0
enjoy!

my blog to make my Ejs simulations more searchable on the internet for open educational resource OER :)
http://weelookang.blogspot.com/2011/05/ejs-open-source-newtons-cradle-java.html