what is the principle used in watches?

Question

i am a student of 10th standard

Answer 1

Most watches now use a quartz crystal. This quartz crystal resonates at a specific frequency. Since frequency is directly proportional to time, by counting the number of cycles it is possible to accurately measure time. I know it sounds circular, but it is based on how basic physics matches up. This gives the watch an independent time standard to tell time. It can also be attached to mechanical systems to allow for mechanical hands to be moved.

Answer 2

All mechanical watches or clocks (i.e. not water clocks and sun dials) use something that produces a rhythmic time interval. This may be a wheel with a heavy rim turning against a light spring that stores and releases energy (a fly wheel) or the vibrations of a quartz crystal or of an atomic molecule. In a clock it can be a pendulum. The rhythmic pulses are counted and used to count the passage of time. In a mechanical watch, an odd device called an escapement not only does the pulse counting but applies pressure to the wheel to move the power in the main spring to the wheel so it does not slow down - each time a count is done, the wheel is given a small kick.

Answer 3

Prior to the use of a quartz crystal to generate a precisely timed electric signal, a pendulum was used; in watches this was duplicated by a tiny weight on a ring, oscillating on a tiny spring. (A larger spring, the one you would wind up, powers the mechanism.)

The pendulum always takes a specific time to make each cycle, and Christian Huygens discovered this and used it to keep time in clocks.

Answer 4

Watches work in many ways. They used to use mechanical gears and pendula and stuff. Now they mostly use the vibrations of a quartz crystal as their time standard.

Check out the wiki link