Mark the following statements as true or false; explain your answers with a sentence or two.
All parallels of latitude have the same length.
False. The Equator is the longest parallel of latitude. Parallels of latitude become smaller as they move away from the Equator toward the poles. The circles marked by parallels of latitude grow smaller as we move northward or southward from the Equator.
The length of a meridian of longitude is half of that of the Equator.
True. A meridian of longitude runs from the North Pole to the South Pole, forming a half-circle. The Equator is a complete circle around the Earth. Since a meridian covers half the Earth's circumference (from pole to pole), its length is half that of the Equator.
The South Pole has a latitude of 90°S.
True. Latitude is measured from the Equator (0°) toward the poles. The North Pole is at 90°N and the South Pole is at 90°S, representing the maximum possible latitude values.
In Assam, the local time and the IST are identical.
False. Indian Standard Time (IST) is based on the meridian at 82.5°E, while Assam is located further east (approximately 92°E to 96°E). Assam's local time would be ahead of IST by about an hour because places to the east experience sunrise and sunset earlier than places to the west.
Lines separating the time zones are identical with meridians of longitude.
False. While time zones are broadly based on meridians of longitude (every 15° representing one hour), the actual lines separating time zones are not perfectly straight. They often follow international borders to respect each country's standard time and avoid dividing countries into different time zones.
The Equator is also a parallel of latitude.
True. The Equator is a parallel of latitude — specifically, it is the parallel at 0° latitude. It is the largest circle among all parallels of latitude and runs east-west around the Earth, halfway between the North and South Poles.
Explanation
(i) The chapter explains that the Equator is the largest circle among parallels of latitude. As latitude increases (moving toward the poles), the circles become progressively smaller until they become points at the poles (90°N and 90°S). (ii) The chapter explains that meridians of longitude are half-circles running from one pole to the other, while the Equator is a complete circle around the Earth. Therefore, the length of any meridian is approximately half the length of the Equator. (iii) The chapter states that latitudes are expressed in degrees, with the Equator at 0° and the poles at 90° North and 90° South respectively. The South Pole is correctly identified as having a latitude of 90°S. (iv) The chapter explains that local time varies with longitude, while standard time is uniform across a country. IST is based on 82.5°E, but Assam lies much further east. Therefore, Assam's local time differs from IST, though the whole of India follows IST for practical purposes. (v) The chapter mentions that time zone boundaries 'are not fully straight' because 'they have to respect each country's standard time and, therefore, tend to follow international borders.' This is why time zone lines deviate from meridians in many places. (vi) The chapter explains that parallels of latitude are imaginary lines running east-west, parallel to the Equator. The Equator itself is the reference parallel at 0° latitude, and all other parallels are measured north or south from it. Therefore, the Equator is indeed a parallel of latitude.