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Time Zones. Time Zones There are 24 hours in one day: There are 24 time zones The world rotates through 360 º Each time zone is 15º wide 360º/24 = 15º. Every place within the time zone has the same time. Known as Standard Time
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Time Zones • Time Zones • There are 24 hours in one day: • There are 24 time zones • The world rotates through 360º • Each time zone is 15º wide • 360º/24 = 15º
Every place within the time zone has the same time. Known as Standard Time • Sir Sanford Fleming, Canadian Engineer and Railway Surveyor proposed the use of time zones to help coordinate arrivals and departures of trains.
In 1884, the system was approved • Started at the Prime Meridian running through Greenwich England. • East ADD time, West SUBTRACT time • The time in that zone is called UT (Universal Time) • Some countries have modified the time zones following the borders of the country or province.(p.38)
Guess the Time?? • http://wwp.greenwichmeantime.com/home.htm
International Date Line • Follows the 180º Longitude. • If you cross the date line moving eastward, you add a day • Moving westward you lose a day • Pg.38
Daylight Savings Time • Many countries change their time according to the season • Cuts down on energy if you don’t have to use the lights until later in the day. • 2012 – Daylight Savings Time occurs on Sunday march 11 (springs forward) and ends on Sunday November 4 (falls back).