As the earth rotates from west to east, those places east of Greenwich...
As the earth rotates from west to east, those places east of Greenwich will be ahead of Greenwich time and those to the west will be behind it (Figure 2.8). The rate of difference can be calculated as follows. The earth rotates 360� in about 24 hours, which means 15� an hour or 1� in four minutes.
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As the earth rotates from west to east, those places east of Greenwich...
**Explanation:**
The earth rotates from west to east, which means that locations to the east of a given point will experience sunrise and sunset before locations to the west. This rotation is the basis for the measurement of time.
**Greenwich Mean Time (GMT):**
Greenwich Mean Time (GMT) is a time standard that is used as a reference for timekeeping around the world. It is based on the median solar time at the Prime Meridian, which passes through Greenwich, London. GMT is used as a reference point for determining the time in different time zones.
**Time Zones:**
To account for the variations in time due to the earth's rotation, the world is divided into different time zones. Each time zone is approximately 15 degrees of longitude wide, with the Prime Meridian (0 degrees longitude) passing through Greenwich, London. As one moves eastward from Greenwich, the longitude increases and so does the time difference.
**Effect on Time:**
As the earth rotates from west to east, the places to the east of Greenwich will be ahead of Greenwich Mean Time. This is because as one moves eastward, the longitude increases, resulting in a time difference.
For example, if it is 12:00 PM (noon) in Greenwich, London (GMT+0), then a place located at a longitude of 30 degrees east (GMT+2) would be two hours ahead of Greenwich time. Similarly, a place located at a longitude of 120 degrees east (GMT+8) would be eight hours ahead of Greenwich time.
Therefore, the correct answer is option **B) Ahead of Greenwich time**.
As the earth rotates from west to east, those places east of Greenwich...
Time is calculated globally based on Greenwich Mean Time, which is also known as World Time.
As the earth rotates from west to east, those places east of Greenwich will be ahead of Greenwich Time and those to the west will be behind it.
Since the earth makes one complete revolution of 3600 in one day (24 hours), it passes through 150 in one hour (360�24) or 10 in every 4 minutes.
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