GREENWICH MEAN TIME
As transportation and communication grew faster in the 1800s , coordinating events between different locations become problematic .High noon in one city is not concurrent with high noon in a city far to the east or the west .The issue was particularly nettlesome for officials trying to coordinate the schedule for the united state's ex panding railroads .
IN 1883 they recommended a standardized system that separated the globe into 24 time zones , each covering 15 degrees of longitude and differing from the adjacent zone by one hour . The Royal Greenwich Observatory in suburban London became the location used around the world to fix the prime meridian .
The longitudinal line assigned 0 degree and Greenwich mean time gradually became the world's reference point for synchronizing watches.
A QUARTZ CRYSTAL shaped like a tiny tuning fork vibrates at a known frequency when exposed to an alternating electric current inside every quartz watch . The interaction of electrical and mechanical properties is called the piezoelectric effect.
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