Well, the thing with the chain is, it depends on the radius of the links, the coarseness of the metal (friction) and the mass of the chain, however, normal chains fall n rope like formations, as far down as they can... Meaning, the closer you hold the two ends together, the less x,z tension there is. Even if you knew the "exact" shape, it would be very dificult to copy it onto a chain in any program... The ball question depends on Vi, and wind resistance. Without Wind resistance, which is very dificult to calculate, a ball will fall at the acceleration of gravity.. 9.8 meters per second. Meaning if the ball is thrown outward from 9.8 meters up it will hit the ground in 1 second, if it is not arched upwards. If you drop the ball from 9.8 meters it will hit the ground in one second. The main thing to remember is that gravity only effects the Y axis, forward velocity is not effected by gravity and therefore does not have to be conidered. Hope this helps.