Social Studies
Is it 9:00 am everywhere in the world?
Why not? Well because of the rotation of the Earth
The Earth makes one complete turn from west to east 360 degrees every 24 hours. It is daylight on the Part of the Earth that is turned towards the sun and night on the part that is away from the sun.
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At 12:00 pm (noon) the sun is directly overhead. But...it would be very confusing if every place had a different time. Eg Ladner 12:00
Delta 12:01, Abbotsford 12:02. So the Earth was divided into 24 time zones. (Why 24? There are 24 hours in a day)
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Time zones are measured by lines of longitude
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How large is each time zone?
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The Earth rotates 360 degrees every day. Each day has 24 hours.
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360
÷
24= 15 degrees. Each time zone is 15 degrees of longitude.
If you travel east you add time, If you travel west you subtract time
Time zones – where does one begin and end?
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The Prime Meridian is the center of a time zone that is 15 degrees wide

 Greenwich Mean time zone (London) (Starting point for time
1) Pacific standard time
2) Mountain
3) Central
4) Eastern
5) Atlantic
6) Newfoundland
Can you name a city
in each time zone?
***Remember: Pac Man Can Eat All Newfies
Because time zones cannot run through populated areas, it would be too confusing. Therefore, time zones often bend around populated areas (Eg. Regina Saskatchewan)
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Could you imagine living in one time zone, and working in another?
There are two ways to determine time in an area.
1) Use the map and count the time zones (1 zone = 1 hour)
Or
2) Use Longitude
Find the longitude of a city and divide the number by 15: whatever the answer is represents the time difference from Greenwich, England