To determine the time at Greenwich when it is 2:00 p.m. at 40 degrees east longitude, we can follow these detailed steps:
Understanding Time Zones
- The Earth is divided into 24 time zones, each generally spanning 15 degrees of longitude.
- Each time zone typically represents one hour of time difference from Greenwich Mean Time (GMT).
Calculating the Time Difference
- The reference point for GMT is 0 degrees longitude (Greenwich).
- Since 40 degrees east is east of Greenwich, it is ahead of GMT.
Determining the Time Offset
- To find the time difference in hours, we calculate:
- 40 degrees east / 15 degrees per hour = 2 hours and 40 minutes.
- Therefore, 40 degrees east is 2 hours and 40 minutes ahead of GMT.
Converting the Time
- Given that the time at 40 degrees east is 2:00 p.m., we need to subtract the time difference to find the GMT:
- 2:00 p.m. - 2 hours = 12:00 p.m. (noon)
- Then, subtract an additional 40 minutes:
- 12:00 p.m. - 40 minutes = 11:20 a.m.
Final Result
- Therefore, when it is 2:00 p.m. at 40 degrees east, the time at Greenwich is 11:20 a.m..
Following these steps ensures accurate time conversion based on the Earth's longitudinal divisions.