Mass Driver

A series of three steel balls are set up on a long rail with a strong magnet at the end of the series. When another steel ball is rolled towards the magnet it is attracted very strongly to it and, though conservation of momentum, the first ball in the series gets launched away at a high rate of speed.
UCB Index: 
Demo Diagram: 



The long plexiglass stand stored in Pimentel 31-1 makes an acceptable track and the steel balls used in A+35+5 stored in 4+2 in Le Conte and 33+4 in Pimentel make good balls for the experiment. The strong magnet I used initially is stored in 54-2 in Pimentel.