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PRACTICAL WORK №3
DETERMINING AZIMUTH AND BEARING
(INVERSE COMPUTATIONS)

PURPOSE

Using UTM coordinates of three points which was found on the topographic
map (Practical work №2) determine the distances and directions between them.

BACKGROUND
A bearing is a compass direction from one point to another on a map or on
the surface of the Earth. Bearings are defined by the angle between a line pointing
north and the line connecting the two points. In the field, a bearing is measured
using a compass, which is an instrument capable of measuring the angle between

a sighted bearing (the direction the compass is pointed) and the direction to the
Earth’s magnetic pole. On a map, bearings are measured using a protractor, with
north generally defined as the direction pointing straight to the top of the map.

THE COMPASS ROSE
The compass rose is the familiar north, east, south, west cross used to show
direction on a map (Figure 3.1).

Azimuth Quadrant

315° N N 45° W N

0 0

NW NE

W E W E

270 90 90 90
SW SE

180 The 0

Compass Rose

S S

Fig. 3.1 The Compass Rose showing both azimuth and quadrant bearings

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