Vector Nature of Angular Momentum and Conservation of the Same

To demonstrate the vector nature of angular maomentum by conserving it about a vertical axis.

Rotating stool, two 3 kilo. dumbells, bicycle wheel, buffer wheel clamped to lecture bench.

Sit on stool with dumbells held straight out 180 degrees apart. Slowly rotate the stool then bring arms in towards body. Angular velocity will increase drastically. Spin up bicycle wheel on buffer and hold its axis vertical while sitting on the stool. Slowly rotate the wheel axis 180 degrees and the stool will rotate in accordance with the law of conservation of angular momentum.