Electronic+Stopwatch

=Electronic Stopwatch Scott Wilson= **Purpose** //What is the fundamental purpose of the device?// ==The purpose of a stopwatch is to time something that you want to know how long it takes to do. Such as an athlete running the 40-yard dash or a swimmer swimming in the Olympics. You can also use it if you were timing somebody on a test or such.== //What energy transformations are seen in its operation?// ===Electrical energy doesn't make the stopwatch light up, but it makes the black appear instead of the normal grey the liquid crystals move with the energy. But without energy the crystals are just normal grey.=== **Controls** //What sensors/controls are designed into the device?// ===In a stopwatch there is a time signal generator that generates a repetitive time signal. A primary circuit for counting the time signal and devoloping the time. A secondary circuit which receives the time signal and displays it on the screen. Lastly, there is an alarm which is connected to the secondary circuit so at set intervals the alarm beeps.=== **Materials** //What material(s) are essential to the device?//
 * Energy**

Wires, buttons, a plastic casing, timer, and lights, Liquid crystal(the "glass" you see through)
**Science** //What scientific principle is central to its operation?//

Time is the scientific principle involed in a stop watch because it is used for timing.
**Design** //What does a typical device look like?//

It looks like a little pocket watch except it has buttons on the top that you can set times with. The electronic stopwatch is no bigger than a cell phone so it fits in your hands or pocket.


**Evolution** //What changes have there been (or could there be) in this device?// ===Breitling invented the first stopwatch in 1915 and is now a luxary watch dealer. It has changed a lot since then and is now smaller than it was in 1915. Since then they made the screens look more high-tech and easier to see the time. The only thing that this device needs is to be brighter to read the numbers better.=== **Related Devices** **Competitors** //What other devices serve a similar purpose?//

Cell phones have stopwatches, IPhone, IPod Mini, IPod Nano, IPod Touch, watches, alarms, timers and clocks.
**Partners** //What other devices work in conjunction with this device?// =A touch plate used for Olympic timing could be a partner because the timing stops when you touch the plate. Also an alarm clock could be a partener because you can set it for a certain time just like a stopwatch.= **Siblings** //What other devices use the same scientific principle?// =Most clocks, watches, and alarms are siblings because they all have timers in them.=