How Do Electric Watches Work?

Electric watches employ a very small electric cell of approximately 1.35 volts. This energy is switched into a coil of wire (electromagnet) that is mounted on a balance wheel. The balance wheel then drives the hands in exactly the reverse manner of a mainspring-driven watch. In 1957 the electric watch was introduced in the United States.
One electric watch uses a tuning fork that drives a ratchet wheel, which in turn drives the hands. It does not use a switch, but a transistor to connect the power to its coils. This combination results in a very accurate timepiece. It does not tick, but hums. The second hand does not move in jumps as is true in most watches, but moves smoothly like a second hand of an electric clock. This watch was introduced in 1961. Self winding watches have a swinging weight geared to the mainspring. As the wearer moves his arm, the weight is swung and the mainspring is wound