10. Notice that
then drawing scale > 1
magnification or
(enlargement)
Drawing scale
If length in drawing > length in reality
11. Example
(2)
A magnifying glass is used to magnify an insect of real
length 0.1mm . If its magnified length is 10 cm ,
calculate the ratio of magnification .
solution
The drawing length : The real
length
Drawing scale
=
`1000 : 1
10 cm =10 × 10 = 100 mm
100 : 0.1
Drawing scale
12. A magnified picture of a butterfly was taken with an
enlargement ratio 200 : 1 , if its real length is 1.2 mm ,
find its length in the picture .
D.L. :
R.L
200 : 1
Solutio
n
…… : 1.2
D.L
=
𝟏. 𝟐 × 𝟐𝟎𝟎
𝟏
=240 mm.
Drawing scale
Example
(3)