Below, the balance is sitting in its place above the magnet. The battery-powered circuit sends a pulse of current through the copper coil. This turns the coil into an electromagnet, and a magnetic field is induced around it. Now magentized, the coil, along with the attached balance, is pulled over toward the side of the magnet having opposite polarity to that of the coil. Once it has moved over fully, a circuit switch, activated by the movement of the balance itself, causes the direction of the current to reverse in the coil. The electromagnet then reverses polarity, and is attracted to the opposite side of the fixed magnet. The procedure repeats six times a second.