Gauss gun

Device that uses magnets and impacts to launch a projectile

The Gauss gun is a device that uses permanent magnets and the physics of the Newton's cradle to accelerate a projectile. Gauss guns are distinct from and predate coil guns, although many works of science fiction have confused the two. Typical use of the Gauss rifle is to demonstrate the effects of energy and momentum transfer, however, self-assembling microbots based on the principle have been proposed for tissue penetration.

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