A good example of chaos is the magnetic pendulum sold as an executive toy. It has four magnets arranged in a square at the base and a pendulum that swings back and forth between them.
(A)
In order to produce chaos, the iteration has to be within what is called a nonlinear system. Nor are all nonlinear systems chaotic: to become so they need to be pushed beyond a certain point, called a bifurcation. Before that point is reached they may behave in a quite orderly fashion.
(B)
Release the pendulum and note the magnets that it visits, and in what order. If the pendulum is released from the same position a second time, the pattern of movement may at first be the same but soon it will become completely different. In fact, the pattern of its movement is chaotic.
(C)
No matter how much care is taken to start the pendulum in the same position, it will visit an entirely different set of points on the two occasions. Chaotic systems are generated by iteration, though not all iteration leads to chaos.
* pendulum: 추(錘) ** iteration: 반복 *** bifurcation: 분기(分岐)
