Hi, I'm new to physlets. in the last days I've been playing a little bit with the simulation builder. however there's something i've been trying, unsuccesfully, to do. I'm interested in making objects crash into each other and then bounce off. as far as I know this is to be done with the Animator.what am i forgetting? thank you very much, jorgenio1.

ps: I've already tried to make objects crash by marking the "Mass" option in the objects' properties.