Phantastic Physics Toys: The Blow Pipe
The Blow Pipe is an inexpensive toy that has been around for a long time. The basic design is a small plastic pipe and a little tiny ball that sits in the pipe. As a person blows air through the pipe the ball hovers above the pipe. The pipe can actually be tipped slightly from side to side and the ball will continue to hover above the pipe. The animation below shows a person using the pipe on the left and a representation of the air flow and the forces on the ball at the right...
