Explain why a rapidly spinning gyroscope, mounted in a frame that allows it to rotate in any direction independently of the frame’s rotation, tends to maintain its axis pointed in the same direction in space.

2 answers

The spinning wheel has angular momentum, lined up with its axis of spin.
If you try to turn that axis, that requires torque, because you are changing the angular momentum vector. (the direction, not the magnitude).
However the frame (gimbals) allow the vehicle to rotate around the spinning gyroscope in any direction without exerting any torque on the spinning wheel. Thus no torque, no change in direction of the spin axis.
At some automobile toll-collecting stations,
a thin metal wire sticks up from the road and
makes contact with cars before they reach the
toll collector.
What is the purpose of this wire?