Question

What influences the duration of the day and night as one moves from south to north?
A.Longitudinal extent
B.Latitudinal extent
C.Tropic of Cancer
D.Tropic of Capricorn

Answer 1

Hint: Latitudes and Longitudes are part of the geographic coordinate system specifying north-south and east-west positioning respectively. They help in specifying the exact location of a place on the Earth surface. Latitude is an angle that ranges from zero degrees at the equator to the ninety degrees at the poles (North and South Poles) and measures the north-south extent of a particular location. Longitudes specify the east-west position on the coordinate system. The Prime Meridian which passes near the Royal Observatory in Greenwich, England is considered as the 0° longitude.

Complete answer: Option A: is incorrect. Longitudes are associated with the earth’s rotation and thus, local time varies with the longitude. A difference of 15° longitude corresponds to a one-hour difference in local time.
Option B: is correct. Because the earth’s own axis is tilted at 23 1/2°, areas tilted towards the sun at a given period experiences summer. The latitudinal extent decides the duration of daylight that an area receives. At the equator, daylight lasts for about 12 hours, regardless of the season. At the time of summer solstice, the sun is directly overhead the Tropic of Cancer and thus areas located around it receive the longer duration of daylight. Similarly, at the time of winter solstice, the sun is directly overhead the Tropic of Capricorn and thus areas around it receive a longer duration of daylight.
Options C and D: are incorrect. Although the location of the Tropic of Cancer and the Tropic of Capricorn affect the duration of day and night as explained above, they are a part of the latitudinal coordinates and thus cannot be taken exclusively.

Thus, The correct answer is Option B.

Note: Duration of day, also defined as daytime, is the time when a given location on the planet receives natural illumination from direct sunlight. Approximately half of the earth experiences daytime at a given time as the planet rotates on its axis.