How does a railgun work?

Answer 1

a friend and i are trying to make one as a school science project. So far we have had limited success in getting a piece of tin foil to move 2mm. we have 17 capacitors and 2 rails they are electrolytic ones and rated upto about 40v DC

Answer 2

A railgun relies on electromagnetic force instead of gunpowder to propel a projectile. Using the left-hand rule and theory on the Lorentz force, a projectile can be propelled at a speed faster than sound using two metal bars, a metal projectile, and a large amount of current. The idea is that the two metal bars are connected to a large source of current that can be released at an instant but will not be activated until the circuit is bridged by the projectile itself (which is also metal).