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# Latitude And Longitude

The surface of the earth is so large that mathematical method can not be employed, it is impossible to locate any place on earth, so for this purpose, imaginery lines are drawn on the globe, these two lines are called latitude and Longitude

Latitude is the one set running east and west parallel to the equator.

The lines that divides the globe in latitudes is called the **equator** which is inclined at an angle 0°

Those lines are called parallel lines of latitude.

Longitude is the one running from north and south passing through the poles.top↑

The straight line that divides the globe in longitude is called the **pole** which is inclined an angle 90°

Those lines are called parallel lines of longitude.

# Longitude

## Meridians Of Longitude

The intersection of the lines of latitudes and the lines of longitudes show the exact location of any place on the earth surface.

For precise location of the map, each degree is subdivided into 60 minutes.top↑

# Latitude

Latitude is the angular distance of a point on the earth surface measured in degrees from the centre of the earth called the equator.

The equator divides the earth into two equal halves, the northern and the southern hemisphere and are parallel to the equator and to each other, hence the latitude are also called **lines of latitude**,

The most important lines of latitude are the equator which is at 0°, the tropical cancer at 23½°N, the tropical capricorn at 23½°S, the arctic circle at 66½°N and the antarctica circle at 66½°S,

The north pole is at 90°N and the south pole is 90°S.top↑

## Uses Of Lines Of Latitudes

1] The lines of latitude in addition with lines of longitude are used to determine the exact location of place on the atlas map.

For example,

Nigeria is located between latitude 4°N and 14°N of the equator and between longitude 3°E and 15°E of the greenwich meridian.

2] Lines of latitude are use to calculate the distance between two places on the earth surface.

# Calculation Of Distance Using Latitude Procedures

a] First locate the two place involved,

b] find the latitude difference between the two places involved.top↑

## Latitude Calculation Procedures

a] if the two places involved are from north to north you **subtract**

North to North = subtract

ai) if the two places involved are from south to south you **subtract**

South to South = subtract

b] If the two places involved are from north to south or from south to north you ** add**

North to South = addition

South to North = addition

c] if it is from the equator 0° to North or South you add or subtract, but the subtraction is useless because equator is always zero.top↑

After getting the latitude difference, you multiply the latitude difference by 111km

1° = 111km

One degree (1°) of latitude is approximately 111km on land.

111km is derived by dividing the length of equatorial circumference;

40,085km divided by 360°

Given the number of degree of latitude between two places, it is easy to calculate the distance between them.top↑

### Example 1

Calculate the distance between the equator of latitude 0° and Egypt of latitude 30°N

#### Solution

Note that equator is always 0°

Locate the two places involved

Equator = Latitude of 0°

Egypt = Latitude of 30°N

From the 3rd procedure

Equator to North or South = addition or subtraction

But equator is always at 0°, so subtraction will have no effect

Latitude difference

= 30° + 0° or 30° - 0° still the same thing

= 30°

Since 1° = 111km

Therefore 30° = (111 × 30)km

= 3330km

The distance between the equator and Egypt is 3330km.top↑

### Example 2

Calculate the distance between South Africa (30°S) and Spain (40°N)

#### Solution

First locate the places involved,

Latitude of South Africa = 30°S

Latitude Of Spain = 40°S

Latitude difference

From South to North = addition

Latitude difference = 30°S + 40°N = 70°

Since 1° = 111km

Hence, 70° = (111 × 70)km

= 7770km

Hence, the distance between South Africa and Spain is 7770.top↑

### Example 3

Calculate the distance between Lagos (4°N) and Cairo (30°N)

#### Solution

First locate the two places involved,

Latitude of lagos = 4°N

Latitude of cairo = 30°N

From North to North = subtraction

Latitude difference = 30°N - 4°N = 26°

Since 1° = 111km

Then 26° = (111 × 26)km

= 2886 km

Hence, the distance between Lagos and Cairo is 2886 km.top↑

### Example 4

If the distance between Lagos (4°) and Bamako, assuming that Lagos and bamako are in the same hemisphere is 1665, calculate the latitude of bamako?

#### Solution

Locate the places involved

Latitude of lagos = 4°N

Latitude of bamako = ?

Latitude difference = can,t be determined, but

Difference in distance can be determine

Difference in distance = 1665 km

Hence, the difference in degrees will be

Since both places are in the same hemisphere which is north,

hence will subtract

(4° - 15°)N = 19°N

Therefore, Bamako is on latitude 11°N

### Example 5

If the distance between South Africa (15°S) and Nigeria is 3885km and they are in different hemisphere, calculate the latitude of Nigeria.

#### Solution

First locate the places involved

Latitude of South Africa = 15°S

Latitude of Nigeria = ?

Latitude difference = can,t be determined, but

Difference in distance can be determine

Difference in distance = 3885km

Hence, the difference in degrees will be

35° + 15° = 50°

Hence, Nigeria is on lat 50°Ntop↑

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