Switch on the power. The spectator pushes the electric button, and then the pulley begins to rotate. After 30 seconds, the big chassis starts to rotate. Then the audience can see the phenomenon of Coriolis force, which is different from the common inertia force and inertia centrifugal force.
Because of the influence of earth rotation, the former movement direction of the object, which moves relative to the earth, will be changed. The movement of elastic woven strip is equivalent to the moving object on the earth. The rotation of the big round disc is equivalent to earth rotation. The movement of woven strip and the big round disc together create the Coriolis force, which makes the positions of the two woven strips change from being mutually parallel to mutual approaching.
Many phenomena in the nature are influenced by Coriolis force, such as cannon shooting and rocket launching and the moving track of typhoon, etc.