It allows each ball to act individually rather than all the other balls to
act as one more massive item hence move as a group with a greatly reduced
velocity.
Alex. F. Burr
In a message dated 10/7/2011 7:53:00 P.M. Mountain Daylight Time,
cvbritton@mac.com writes:
a 'Good' Newton's Cradle actually has a
small spacing between the spheres. A paper thickness or so IIRC.