4.3 Calculating area oo a map

Social sciences

Geography

Map work

Grade 9

Module 14

Calculating area on a map

Calculating area on a map.

Example

Steps:

1. Measure length in cm and convert to m / km.
2. Measure width in cm and convert to m / km.
3. Apply formula – L x W.
4. Write the answer in km² / m².

Always take note of the unit in which the answer must be given – this will usually be m² or km².

ACTIVITY 1: [LO 1.3]

1. The length of a rectangular object is 5,6 cm and the width is 3,4 cm on a 1 : 50 000 topographic map. Calculate the area of the object in km².
2. The length of a building is 1,1 cm and the width is 0,6 cm on a 1 : 50 000 topographic map. Calculate the area of the building in m².Calculating time between 2 points.

Remember the following:

The distance completed will have to be calculated from the map and be given in real km. Speed or time will always be provided.

How long will it take to travel by car at 60 km/h from point A to point B?

Steps:

ACTIVITY 2: [LO 1.3]

At what time will a person arrive at a destination if he or she leaves the house at 7:00 and travels a distance shown as 8 cm on a 1 : 50 000 map? Reading and analysing maps

Topographic maps are among the most useful and precise maps that are available because of the amount of detail that they contain and the precision with which the minutest details are indicated.

Topographic maps and orthophoto maps provide the geographer’s tools (SOURCE) and the reader needs to understand the language of the map. This makes it possible to give scientific explanations of features.

The activities that follow will help the learner to master map-reading techniques and skills and to extend his or her knowledge of Bloemfontein.

ACTIVITY 3: [LO 1.7]

Consult your atlas to answer the following questions:

• Find out where Bloemfontein is situated by using the index at the back of the atlas.
• In which province of South Africa is Bloemfontein?
• Indicate the direction to Durban from Bloemfontein.
• Measure the distance between Edenburg (south of Bloemfontein) and Bloemfontein in km, using the linear scale given for the map in your atlas.
• At what time will a bus arrive in Bloemfontein if it leaves Edenburg at 10:00 and travels at an average speed of 120 km/h, without stopping along the way?
• Read the accompanying text and answer the questions dealing with Bloemfontein’s past.

Provide reasons for the city’s:

• 1. origin;
  2. development as a city.
• The development of Bloemfontein
• More that a hundred years ago, trekkers from the Cape settled in the environment of Bloemfontein, which quickly developed into a centre for trading. In 1846, the location of the present city was selected by Major Warden as the most convenient site for building a fort and a residential area. From this beginning, and in spite of setbacks resulting from unrest and wars, which inhibited its development, the small town developed into an attractive city.
• Bloemfontein forms the geographical hub of South Africa’s railway, road and airline services. The development of the Free State gold mines, less than 160 km from the city, has brought additional prosperity to the city, which is fast becoming an important industrial centre.
• The city is situated in a picturesque environment in the heart of the Free State plateau, surrounded by hillocks and hills rising high above the plains. To the north is Naval Hill, from where there is a particularly beautiful view of the city.