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LIVE: MAPWORK SKILLS 13 NOVEMBER 2014

Lesson Description

In this lesson we:

Discuss the following: o Locating exact position: degrees, minutes and seconds o Scale: word, ratio, and line scale o Direction: Magnetic Declination o Distance: measuring distances and converting to ground distance along a straight line

Challenge Question

How many Topographical Maps (1:50 000) would you need to map the entire South Africa

Summary

Reference Numbering – 1 : 50 000

Declination

The information on the MARGIN of the map

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True North is shown by the vertical straight line

Magnetic North is shown by the arrow pointing to the west of True North

The Magnetic Declination can be measured as the angle between the Magnetic

North and the True North

The Mean magnetic declination is 20 35 west of True North

The Mean annual change is 6 Westwards

The year the map was drawn is 2001

Test Yourself

Refer to the Topographical map of Schoemansville 2527DB

Question 1

The map index/reference of the topographical map to the west of Schoemansville is

A 2527DA.

B 2527DD.

C 2628CA.

D 2528CA.

Question 2

The Krokodil rivier flows in a ... direction.

A south-east

B north-west

C north

D south

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Question 3

Schoemansville is a/an ... town

A industrial

B recreational

C dormitory

D mining

Question 4

The contour interval on the map is ... metres

A. 5

B 10

C 15

D 20

Question 5

The dam wall in D3 is ... metres

A 1162

B 1166,4

C 1170,7

D 1181.1

Question 6

The natural geormorphological landform of the north facing slope that is formed by the Hartebeesfontein mountain slope is a ...

A. valley

B interlocking spur

C gorge

D gap

Question 7

The major landuse in block B3 is...

A cultivated land.

B orchards and vineyards.

C recreational.

D Diggings.

Question 8

The dominant economic activity to the east of Schoemansville is...

A primary

B secondary

C tertiary

D quartenary

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Question 9

The development of Hartbeespoort Dam as a tourist destination is not due to the ... at the edge of the dam.

A Holiday resort

B Snake park

C Yacht club

D sewage works

Question 10

The row of trees along the river in B1 is for the ...

A channelling of water along the river.

B Prevent water entering the flood plain.

C Reduce the erosive power along the river banks.

D for aesthetic value.

Exam Questions

Question 1

1.1 Calculate the distance between the T-junctions between Schoemansville and Melodie. (3 x 1) (3)

1.2. Calculate the area of B1. (4 x 1) (4)

1.3. Calculate the magnetic declination for the present year using the information below. (5 x 1) (5)

Mean Magnetic Declination: 23,7º West of True north

Mean Annual change: 3` westwards

Year on map: 2002

1.4. (a) Is the Aerial cableway station at trig. Beacon 66 in C6 intervisible from the tunnel entrance at D3. (1 x 2) (2)

(b) Provide a reason for your answer. (1 x 2) (2)

(c) State and give a reason for the direction of flow of the Krokodilrivier. (2 x 1) (2)

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