Techniquest

Exhibit: Air Cannon

Bang the rubber sheet at the back of the cannon to produce a ring vortex.  This is just like a smoke ring but without the smoke!  See the shape of the ring as it hits the target screen. When you hit the barrel, a vortex is fired at the target.  As a vortex, air travels directly instead of following its usual diverse pathways. Note how the hole at the front is much smaller than the barrel.  This helps create a very powerful, fast-moving vortex.