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Earth grid or Geographic grid
  • A grid-like pattern formed by the imaginary lines of latitude and longitude on the earth's surface, known as the Earth grid or Geographic grid.
  • The latitudinal and longitudinal extensions are required to locate precisely any place on earth.
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Time on Earth
The Earth takes one day to rotate on its axis.
■■ \(1\) day \(=\)\(24\) hours
■■ \(1\) hour \(=\)\(60\) minutes
■■ \(24\) hours \(=\)\(24\ x\ 60\)\(=\)\(1440\) minutes
■■ The angle of the earth \(=\)\(360 °\)
■■ \(360 °\)\(=\)\(360\) Longitudes
■■ \(360 °\)\(=\)\(1440\) minutes
■■ So \(1 °\)\(=\)\(1440/360\)\(=\)\(4\) minutes
■■ In \(4\) minutes \(=\)\(1°\) rotation
■■ In \(60\) minutes \(= 60/4 = 15°\) rotation
■■ So, in an hour (\(60\) minutes) the earth rotates \(15°\)