Question

What does the word meridian mean?
A) New day
B) Midday
C) Night
D) Daylight

Answer 1

Hint: A (geographic) meridian (or line of longitude) is half of an imaginary great circle on the Earth's surface, a coordinate line terminating at the North Pole and the South Pole, linking locations of equal longitude measured in angular degrees east or west of the Prime Meridian.

Complete answer:
The term meridian comes from the Latin word meridies, which means "midday." At noon, the subsolar point passes over a certain meridian, midway between sunrise and sunset on that meridian. At the same time, the Sun crosses the celestial meridian. The phrases a.m. (ante meridiem) and p.m. (post meridiem) are derived from the same Latin stem and are used to distinguish hours of the day when using a 12-hour clock.

The longitude and latitude of a place on the meridian, measured in angular degrees north or south of the Equator, determine its location. All circles of latitude are perpendicular to each meridian. On the Earth's surface, meridians are half of a big circle. On a current ellipsoid model of the world (WGS 84), the length of a meridian has been calculated to be 20,003.93 km (12,429.9 miles).

Other meridians were established by the angle at the centre of the globe between where it and the prime meridian cross the equator, whereas the Prime Meridian via Greenwich (within Greenwich Park), England, was set at zero degrees of longitude. Because there are 360 degrees in a circle, the antimeridian, which lies on the opposite side of the earth from Greenwich, forms the second half of a circle with the one passing through Greenwich and is located near the International Date Line at 180 degrees longitude (with landmass and island deviations for boundary reasons).

Hence the correct answer is option 'B'.

Note: The Western Hemisphere is defined by the meridians from West of Greenwich (0°) to the antimeridian (180°), whereas the Eastern Hemisphere is defined by the meridians from East of Greenwich (0°) to the antimeridian (180°).