Map reading & topographic interpretation：練習問題

Original chapter practice: 40 marks. Suggested time: 60 minutes (Thinka practice estimate, not an official exam duration). Answer all 10 questions. All sites and numerical datasets are synthetic teaching examples. This is not a full official HKDSE paper. Use a calculator, ruler and pencil; show units and working.

Figure M is a synthetic topographic teaching map. What is the six-figure grid reference of A?

A route is 7.5 cm long on a correctly printed 1:20,000 map. Its ground distance is:

In Figure M, which side of the hill is steeper between the 40 m and 80 m contours?

A slope rises 60 m over a horizontal distance of 1,200 m. Which pair is correct?

Where contours cross a stream and form V shapes pointing towards higher land, the V tips usually point:

Use Figure M. Treat the plotted positions as exact for calculation. (a) Give the grid bearing of B from A and the reverse bearing. [2] (b) Calculate the straight-line ground distance AB to the nearest metre. Show your method. [3]

A rectangular field is 4 cm by 3 cm on a correctly printed 1:5,000 map. (a) Calculate its ground dimensions and area in m². [3] (b) Explain why doubling both dimensions when enlarging the printed map changes the representative fraction, but not the ground area. Give the new fraction. [2]

A synthetic contour extract has successive labelled lines 40, 60, 80 and 100 m. Point P lies halfway in horizontal distance between the 60 and 80 m contours on an approximately uniform slope. (a) State the contour interval and estimate P’s elevation. [2] (b) The 60 m and 100 m crossings on a transect are 500 m apart horizontally. Calculate the percentage gradient and explain one limitation of this average. [3]

A synthetic settlement is choosing a clinic site. Source: C is on 2° land beside an all-weather road, 200 m from most homes and 30 m from a stream on its floodplain. D is on 15° land, 1,200 m from homes along a steep footpath, 300 m from the stream and outside the mapped floodplain. Both plots are large enough. (a) Compare two advantages of C over D using the source. [4] (b) Explain a risk at C and a possible response. [2] (c) Make a conditional recommendation, and identify two further checks with reasons. [4]

Synthetic profile data: distance from A (m) 0, 200, 400, 600, 800; elevation (m) 20, 40, 80, 60, 20. (a) Draw and label the profile on the supplied axes. [4] (b) Calculate the average percentage gradient from 0 to 400 m. [2] (c) Observers at 0 and 800 m each have eyes 2 m above ground. Can they see one another along this profile? Explain. [2] (d) For a separate printed profile, horizontal scale is 1 cm to 200 m and vertical scale 1 cm to 20 m. Calculate vertical exaggeration and state its visual effect. [2]