Soda Bottle Cyclone Tornadoes don't travel as far or get as big as hurricanes, but their powerful, twisting winds are the fastest and most dangerous on Earth. At the centre of the tornado is a spinning column of air called a vortex.
Some tornadoes even have more than one vortex.
This project lets you see what a tornado's vortex looks like. Take the caps off both the pop bottles. Place the caps together and put a bead of silicon around the hole to seal it. Wrap a piece of duct tape around the outside of the two caps to firmly join them together. Screw the double cap onto one of the pop bottles.