Standard, International Time & Great Circle

Today’s topic is Standard And International Time

Standard And International Time

Standard Time

Standard time is the time generally adopted by a country, Nigeria as an example, which is usually taken from the central meridian of that country and its spans within 15° of longitude.

Standard time is also refer to as winter time or summer time as in case of United kingdom and it is not always adopted in some countries, such as Indian, Afghanistan, Australia but instead they adopt Daylight Saving Time (DST)

Note : Australia is the only country that is categorize as a continent and also as a country. So if someone should ask, What continent is Australia? It is Australia.

Greenwich Mean Time (GMT)

Greenwich Mean Time (GMT) is a standard time for all the world time. The need for standard time is to eliminate the differences between the local time of one town and the other in the same country, otherwise time will have to change from one town to another.
standard time falls within its time zones.

International Date Time

longitude 180 west and east are zigzag in structure in order to avoid cutting across islands.
Date changes by one day when crossed east or west crossing to the east, and gain a day when crossing to the west to be a day.

That is the definition of standard and international time, now let go to great circle.

Great Circle

Great circles refers to any circle that divides the earth into two equal parts.

The equator is the only time of latitude that is great circle.

So meaning, two opposite lines of latitudes make a great circle. Please Note this. E.g 180°E and 180°W or 90°E and 90°W.

Note : the shortest distance between any two points on the earth surface along the circumference of the great circle which passes these route is often used by Aircraft along distance journey. E.g Polar air route between London and los Angeles over Greenland.

Important Note : Infinite number of great circles are found on the lines of longitude.

That is all on Standard and international time. Till next class where will be talking about The Structure Of The Earth but don’t forget to write a comment, thank you.


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