Map Scale and Azimuth

Scale relates the distance on a map to the actual distance on the ground. Azimuth shows direction as an angle.

Scale

• Scale: the ratio of map distance to ground distance.
• Types: numerical (1:100 000), verbal (1 cm to 1 km), linear.
• Distance = map distance × denominator.
• For example: 3 cm × 50 000 = 150 000 cm = 1,5 km.
• The smaller the denominator, the larger the scale: a 1:10 000 scale is larger and more detailed than 1:1 000 000.

Converting cm to km: 100 000 cm = 1 km.

1. Measure the distance on the map (cm)
2. Multiply by the denominator
3. Convert cm to km (÷ 100 000)

Azimuth

• Azimuth: measured clockwise from north (0°-360°).
• North is 0°, East 90°, South 180°, West 270°.
• Back azimuth = azimuth ± 180°.
• Instruments: compass, protractor.

Direction	Azimuth
North	0° (360°)
East	90°
South	180°
West	270°

Example: if the azimuth is 100°, the back azimuth is 100 + 180 = 280°. If the azimuth is 250°, then 250 - 180 = 70°.