Textbook of Engineering Drawing, Second Edition

3.4 Textbook of Enginnering Drawing------------------

-'I 5.5m

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10 5 o (^2 3 4 5)
DECIMETRE RF=l/50 METRES
Fig. 3.3

Problem 3 : The distance between two towns is 250 km and is represented by a line of

length 50mm on a map. Construct a scale to read 600 km and indicate a distance of 530 km

on it.

Solution: (F ig 3.4)

1. Determine the RF value as ---50mm^50 1
   250km 250x 1000x^1000 =^5 X^106


2. Obtain the length of the scale as: 1 x 600km = 120mm.
   5xl06


3. Draw a rectangular strip oflength 120 mm and width 5 mm.


4. Divide the length into 6 eq1}AI parts, each part representing 10 km.


5. Repeat the steps 4 to 8 of construction in Fig 3.2. suitably.


6. Mark the distance 530 km as shown.

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100 50 0

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100

530km

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300

Fig. 3.4

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400 500