LONGITUDE AND LATITUDE II Lesson Note

LEARNING OBJECTIVES

By the end of the lesson, students should be able to:

1.Define lines of latitude.

2.Explain how distance is calculated using lines of latitude.

3.State the relationship between latitude and distance on the Earth’s surface.

4.Calculate the distance between two places using their latitudes.

CONTENT

LINE OF LATITUDE

Lines of latitude are imaginary circles drawn around the Earth from east to west. They are used to determine the position of places north or south of the Equator.

The Equator is at latitude 0⁰. The North Pole is at latitude 90⁰ N, while the South Pole is at latitude 90⁰ S.

The distance between two places on the same meridian can be calculated using their latitudes.

Formular for calculating distance using latitude:

Distance = Differences in latitude × 111 km

One degree of latitude is approximately = 111km on the earth surface.

Work Example

Example 1: Calculate the distance between a place at 10 degrees north and another at 20 degree North

Solution:

Step 1: Find the difference in latitude.

20 degree - 10degree= 10 degree

Step 2: Multiply the difference by 111 km.

10× 111= 1,100km

Answer: 1,110 km.

Example 2: Calculate the distance between a place and another place at 15 degrees north and another place at 5 degree south.

Solution:

Since the places are on opposite sides of the Equator, add their latitudes.

15 degrees + 5degrees =20 degrees

Then multiply by 111 km.

20×111km =2,220km

Answer: 2,220 km.

Example 3: Find the distance between two places at 30 degree south and 50 degree south

Solution:

Step 1: Find the difference in latitude.

50 degrees - 30 degrees = 20 degrees.

Step 2: Multiply by 111 km.

20× 111km =2220km

Answer: 2,220 km.

Note: These calculations give the approximate north–south distance along a meridian. If the places are on different meridians, their actual distance apart cannot be determined from latitude alone.