Question

2 cities have nearly the same north-south line 90° W. The latitude of the first city is 23°N, the latitude of the second city is 36° N. Approximate the distance between the cities if the average radius of earth is 6400 km. The cities are approximately

Answer 1

The cities are approximately 1452 km apart

Explanation:

The two cities are on the same Longitude 90°W therefore the distance between them is on a great circle

Latitude of the first city = 23°N

Latitude of the second city = 36° N

Because their latitude are on the same polar axis, we subtract to get the angular difference

Angular Difference = 36 -23 =13°

`Distance= (\alpha)/(360) X 2\pi R`

where
`\alpha = Angular Difference, R= radius of the earth`

`Distance= (13)/(360) X 2\pi X 6400=1452.11km`

The cities are approximately 1452 km apart