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UNIT 11

DISTANCE MEASUREMENTS

I. READING AND LEARNING

Task 1. Read and memorize the following words and word-

combinations:
scale – масштаб, зображувати в масштабі;

control points – опорні точки;
graduated tapes – мірна стрічка;
inter-point distance – відстань між точками;

steel tape – сталева рулетка;
measuring rope – рулетка;
subtense bar – базисна високоточна лінія;

survey line – лінія зйомки, візирна лінія;
offset – зміщення;
reconnaissance – рекогносцирування, схематична карта;

pace – швидкість, довжина кроку;
modulate – модулювати.

Task 2. Read and translate the text.

Text 1. Distance measurements

Distance is one of the fundamental measurements in surveying.
Distance is required in many instances, e.g. to give scale to a
network of control points, to fix the position of topographic detail by

offsets or polar coordinates, to set out the position of a point in
construction work, etc.
Distances may be measured by four methods: direct, optical,

electromagnetic or GPS.
The method used for any particular job depends upon the nature
of the ground, the range, the accuracy, the number of distances to be
measured, the time available, the cost and the availability of the

equipment.
For hundreds of years, graduated tapes (measuring ropes, tape
measures and steel tapes), subtense bar: a tripod-mounted bar having

the target precisely 2m apart, have been used to measure distances by
means of direct comparison. The major flaw of such method,
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