A coilgun is a type of synchronous linear electric motor which is used as a projectile accelerator that consists of one or more electromagnetic coils. These are used to accelerate a magnetic projectile to high velocity. The name Gauss gun is sometimes used for such devices in reference to Carl Friedrich Gauss, who formulated mathematical descriptions of the electromagnetic effect used by magnetic accelerators.
Coilguns consist of one or more coils arranged along the barrel that are switched in sequence so as to ensure that the projectile is accelerated quickly along the barrel via magnetic forces. Coilguns are distinct from railguns, which pass a large current through the projectile or sabot via sliding contacts.
Electromagnetic projectile devices which use electromagnetic means to accelerate solid materials, such as Kinetic energy weaponry, Gauss guns, Mass drivers or Railguns are often used in fiction, especially science fiction.
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