This set of Engineering Drawing Multiple Choice Questions & Answers (MCQs) focuses on “Representative Factor – 1”.

a) ratio of the length in drawing to the actual length

b) ratio of the actual length to the length in drawing

c) reciprocal of actual length

d) square of the length in drawing

View Answer

Explanation: Representative fraction is the ratio of the length of the object represented on drawing to the actual length of the object represented.

2. The scale of a drawing is given as 1:20. What is the representative fraction?

a) 20

b) 1/20

c) 0.5

d) 0.02

View Answer

Explanation: The scale of drawing is given as 1:20 that is a reducing scale, this means dimensions are made to 1/20th of full size. So the representative factor is that dimension in drawing to actual dimension. R.F. = (1/20)/1 = 1/20.

3. The scale of a drawing is given as 15:1. What is the representative fraction?

a) 15

b) 0.15

c) 1.5

d) 1/15

View Answer

Explanation: The scale of drawing is given as 15:1 that is a enlarging scale, this means dimensions are increased to 15 times of actual ones. So the representative factor is that dimension in drawing to actual dimension. R.F. = 15/1 = 15.

4. The length of the drawing is 50 mm, the scale is given as 1:5. Find the actual length.

a) 50 cm

b) 10 cm

c) 25 cm

d) 10 mm

View Answer

Explanation: The scale given is 1:5 (reducing scale) that is the drawing is made with 1/5th of actual dimensions. So we have to multiply the drawing length with 5. 50 mm x 5 =250 mm and 1 cm =10 mm. The actual length in cm is 25.

a) 1/5

b) 20

c) 1/20

d) 5

View Answer

Explanation: Representative factor is the ratio of the length represented in drawing to the actual length. Here given actual length is 1 m =100cm and length of drawing is 5 cm. R.F. =5 cm/100 cm = 0.05 (or) = 1/20.

6. The representative factor is 4. The actual length is 20 mm. Find the length of drawing.

a) 5 cm

b) 5 mm

c) 0.2 mm

d) 8 cm

View Answer

Explanation: The representative factor given is 4 (more than one), shows the scale is enlarging. Representative factor = ratio of length in drawing to actual length. R.F. = (length in drawing)/20 mm = 4.

Length in drawing = 20 mm x 4 = 80 mm = 8 cm.

7. A machine part is drawn two times with different scales. The ratio of 1st drawing’s R.F. to 2nd drawing R.F. with respect to actual object is found to be 2. The length of second drawing is 10 mm. Find the 1st drawing length.

a) 5 mm

b) 200 mm

c) 5 cm

d) 2 cm

View Answer

Explanation: 2= 1st drawing R.F/2nd drawing R.F. =(length of 1st drawing/ actual length)/(length of 2nd drawing/ actual length) = length of first drawing/ length of second drawing= length of first drawing/ 10 mm. 2 x 10 mm = 20 mm. So therefore the length of first drawing is 20 mm = 2 cm.

8. The length of the drawing is 20 cm, the scale is given as 2:1. Find the actual length.

a) 50 cm

b) 10 cm

c) 25 cm

d) 10 mm

View Answer

Explanation: The scale given is 2:1 (enlarging scale) that is the drawing is made 2 times of actual dimensions. So we have to divide the drawing length with 2. 20 mm / 2 =100 mm and 1 cm =10 mm. The actual length in cm is 10 cm.

a) 1/30

b) 30

c) 0.03

d) 15

View Answer

Explanation: Representative factor is the ratio of the length represented in drawing to the actual length. Here given actual length is 1 cm and length of drawing is 30 cm. R.F. =30 cm/1 cm = 30.

10. The representative factor is 0.02. The actual length is 50 cm. Find the length of drawing.

a) 10 cm

b) 5 cm

c) 0.25 cm

d) 10 mm

View Answer

Explanation: The representative factor given is 0.02 (less than one), shows the reducing scale. Representative factor = ratio of length in drawing to actual length. R.F. = (length in drawing)/50 cm = 0.02. Length in drawing = 0.02 x 50 cm = 1 cm = 10 mm.

11. The ratio of length of actual object to length of drawing is given as 5. Find the scale and R.F. (Representative factor).

a) 1:5, 1/5

b) 5:1, 1/5

c) 1:5, 5

d) 5:1, 5

View Answer

Explanation: Given that the ratio of actual length to length of drawing which is reciprocal of R.F. So the R.F. for given values is 1/5. From the given information it can be understood that the actual object is 5 times larger than the drawing, so the scale is reducing scale i.e. 1:5.

12. The representative factor is 2, the drawing length is 100 mm. Find the actual length.

a) 20 cm

b) 50 mm

c) 20 mm

d) 50 cm

View Answer

Explanation: The scale is enlarging scale. The ratio of length of drawing to actual length gives the representative factor. 100 mm / actual length = 2, actual length = 100 mm/2 = actual length = 50 mm (or) 5 cm.

13. The representative factor is 0.5, the drawing length is 10 cm. Find the actual length.

a) 20 cm

b) 50 mm

c) 20 mm

d) 50 cm

View Answer

Explanation: The scale is reducing scale. The ratio of length of drawing to actual length gives the representative factor. 10 cm / actual length = 0.5, actual length = 10 cm/0.5 = actual length = 20 cm (or) 200 mm.

**Sanfoundry Global Education & Learning Series – Engineering Drawing.**

To practice all areas of Engineering Drawing, __here is complete set of 1000+ Multiple Choice Questions and Answers__.