Railgun
medium- to large-caliber railguns is in the millions of amps.
The rails are lengths of conductive metal, such as copper. They can range from 1.2 to 9 meters
long.
The armature bridges the gap between the rails. It can be a solid piece of conductive metal or a
conductive sabot -- a carrier that houses a dart or other projectile. Some railguns use
a plasma armature. In this set-up a thin metal foil is placed on the back of a non-conducting
projectile. When power flows through this foil it vaporizes and becomes a plasma, which carries
the current.
Picture 1. Basic parts in a railgun
Source: http://www.seminarsonly.com/mech%20&%20auto/railgun-seminar-report-ppt.php
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The armature may be an integral part of the projectile, but it may also be configured to accelerate
a separate, electrically isolated or non-conducting projectile. Solid, metallic sliding conductors
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