Fundamentals of Surveying (FS) Practice Exam

Which term describes lines that measure the arc distance east and west?

1. Latitude

2. Longitude

3. Equator

4. Parallels

The correct answer is: Longitude

The term that describes lines measuring the arc distance east and west is longitude. Longitude lines, also known as meridians, run from the North Pole to the South Pole and are used in conjunction with latitude to pinpoint a location on the Earth's surface. They help in defining geographical coordinates, enabling us to establish how far east or west a location is from the Prime Meridian, which is set at 0 degrees longitude. Latitude, in contrast, refers to the measurement of distance north and south of the Equator and is represented by horizontal lines, known as parallels. The Equator itself is the central line from which latitude is measured, situated at 0 degrees. While parallels also play a role in geographic coordinates, they specifically relate to the north-south measurement rather than east-west. Thus, longitude is the correct term for lines indicating the arc distance in an east or west direction.