[quote]
If the mass of all the balls are exactly the same, the energy will transfer from one side to another side (from one ball to the next one, ...).
[/quote]
yeah i know that ,but Is there a physical equation simulate the transfer of energy?? and how it can be programmed?? :)
[quote]
If the mass are not exactly the same , it is possible to cause all the ball moving (is this what you called vibration?)
[/quote]
no, when i saw the lookang's project(newton's cradle) i saw the balls vibration after the period of time?how?

[quote]
I would suggest you do the experiment and find out the ANSWER by yourself ;).
[/quote]

ok i'll try ;)