| Description: |
A bicycle wheel is mounted on a rod, and a string is fixed on the end
of the rod. The system is hung to the ceiling of the classroom by the string.
Make the wheel spin by using an electrical motor with friction wheel. Due
to the gravitational torque, the wheel will precess about a vertical axis
when it is spinning. The instructor then places an additional torque on
the system by trying to force the precession around the vertical axis.
When he does this (with some practice) the angular momentum of the wheel
will align itself with the applied torque, i.e., the gyroscope will rise
to a vertical position. |