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UNIT 10

ANGULAR MEASUREMENTS

I. READING AND LEARNING

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

combinations:
horizontal angle – горизонтальний кут;

intersecting lines – лінії, які перетинаються;
summit – вершина, зеніт;
datum plane – базова площина, рівнева поверхня;

expressed in degrees – виражений у градусах;
right angle – прямий кут;
corners of a square – кути квадрата;

high-precision instruments – високоточні інструменти;
home-made graphometer – виготовлений в домашніх
умовах графометр, кутомір;

plane-table – мензула (геодезичний прилад);
miscellaneous instruments – інструменти змішаного типу;
horizontal circle – горизонтальний круг;
circular plate – кругла пластина, диск.

Task 2. Read and translate the following text

Text 1. Horizontal angles

Horizontal and vertical angles are fundamental measurements in

surveying. In topography, the angle made by two ground lines is
measured horizontally, and is called a horizontal angle. Horizontal
angle is the difference between 2 intersecting lines when they are

projected onto the datum plane. Horizontal angles are used for
determining bearings and directions in control surveys, for locating
detail when mapping and for setting out all types of structure.
You may replace the ground lines of horizontal angle by two lines

of sight AB and AC. These lines of sight are directed from your eyes,
which form the summit A of the angle BAC, towards permanent
landmarks such as a rock, a tree, a telephone pole or the corner of a

building.

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