First, the tools we need to prepare are batteries, magnets and copper coils. Small magnets with the same poles (both N and S) are attached to the positive and negative poles of the battery respectively. Then put the battery into the copper wire loop. At this time, you will find that the battery keeps shuttling in the copper wire circle.

Small magnets are the key points in this experiment. They not only generate a magnetic field, but also act as conductors, so that the copper coil and the positive and negative electrodes of the battery are connected. Even if a current is generated in the copper coil, the electrified copper coil generates a magnetic field according to the law of electromagnetic induction and the right-hand rule.