Page 70 - Geography_n_Environment

B can be converted into the ground distance using a linear or
representative fractional scale, following these steps:

(i) Place a ruler on the linear scale by aligning its zero (0)
with a zero (0) on the linear scale, and the red mark on
the right side;
FOR ONLINE READING ONLY
(ii) if the red mark is aligned with a certain number, that number
on a linear scale represents the ground distance between
points A and B;

(iii) If the red mark is between two numbers, record the left
number and mark its position on the ruler as shown in
Figure 11. For example, the left number in Figure 11 is 2
km, then record it;

(iv) move the ruler to the left of a linear scale to align the right
red mark with zero (4) (the left red mark will be on left side
(5);
(v) record the closest number to the left red mark. For

example, in Figure 11 the recorded number is 750 metres.
(3)
Metre 1000 500 0 1 2 3 Kilometre
Therefore, the ground distance from point A to B is 2 km
and 750 metres.

1000 (3)
Metre 500 0 1 2 3 Kilometre

1000 (5) (4)
Metre 500 0 1 2 3 Kilometre

1000 (5) 500 (4)
Metre 0 1 2 3 Kilometre

Figure 11: Converting map distance to ground distance when the right red mark

representing point B is between two numbers on a linear scale.
GSPublisherVersion 0.5.100.100

63
GSPublisherVersion 0.5.100.100

21/11/2024 16:58
GEOGRAPHY AND THE ENVIRONMENT-STD 4.indd 63
GEOGRAPHY AND THE ENVIRONMENT-STD 4.indd 63 21/11/2024 16:58