1. Guidelines for dimensions at international level on a drawing is controlled by __________
a) Bureau of Indian Standards
b) Corporate drafting standards
c) ANSI
d) ISO
Explanation: ISO (International Organization for Standardization), this is a World Wide organization that creates engineering standards, dimensions with approximately 100 participating countries. ANSI creates standards for North America, BIS for India, CDS for small company.
2. The symbol shown below is _________
a) Radius
b) Depth
c) Diameter
d) Angle
Explanation: The above symbol is used for diameter of circles irrespective of the units. The diameter symbol ⌀ is distinct from the empty set symbol ∅, from an (italic) uppercase phi Φ, and from the Nordic vowel ∅.
3. When drawings are drawn smaller than the actual size of the objects the scale used is said to be _________
a) Enlarging scale
b) Reducing scale
c) Small scale
d) Decreasing scale
Explanation: Dimensions of large objects must be reduced to accommodate on standard drawing sheets. It is not any physical instrument but a ratio taken between actual and drawing objects, the drawing is drawn small and this ratio is termed as reducing scale. Don’t get confused as reducing-scale is also used by surveyors for reducing chains and links to acres and roods
4. The ratio of the length of the drawing of the object to the actual length of the object is called ___________
a) Resulting fraction
b) Representative figure
c) Representative fraction
d) Representative index
Explanation: Representative fractions are a unit-less relation between one “unit” on the map and however many “units” of the same type on the ground. When a 1 cm long line in a drawing sheet represents 1 m length of the actual object on the ground, the R.F is equal to 1 cm/1 m = 1/100. These are of 3 types-full scale, reduced scale and enlarged scale.
5. The scale of chords is used to measure _________
a) Chords
b) Lines
c) Angles
d) Diameter
Explanation: Used to read angle if there is no protractor. To draw an angle, compasses describe an arc from origin with a radius taken from the 60 mark. The required angle is copied from the scale by the compasses, and an arc of this radius drawn from the sixty mark so it intersects the first arc. The line drawn from this point to the origin will be at the target angle.
6. What is the use of circular vernier as a measuring instrument?
a) Measuring small angle
b) Measuring large angle
c) Measuring required accurate angle
d) Normal angle
Explanation: Measuring required accurate angle
7. If the measurement required is in three units, which scale would you prefer?
a) Plain
b) Comparative
c) Diagonal
d) Vernier
Explanation: Diagonal scales are used when very minute distances such as 0.1 mm etc. are to be accurately measured or when measurements are required in three units; example- dm, cm and mm, or yard, foot and inch. While other options only give measurement in single unit
8. Vernier scale consists of two important parts, vernier scale and _________
a) Secondary scale
b) Initial scale
c) Main scale
d) Large scale
Explanation: The scale on the larger, fixed portion of the calliper. It gives the most significant digits in the reading, while the vernier is the sliding portion giving the least significant digits in the reading. It can be further divided into sub-parts as internal jaws, external jaws, locking screw etc.
9. A room of 1728 m3 volume is shown as 216 cm3 volume on a drawing sheet. What is the R.F?
a) 1/20
b) 1/200
c) 1/250
d) 1/186
Explanation: Since volume is given, formula will turn as
R.F = (drawing volume/original volume)3
R.F = (216 cm3 / 1728 * (100)3 cm3)3
= 1/200.
10. The area of field is 25,000m2. Length and breadth of the field, on the map is 5cm and 5cm respectively. What is the Representative Fraction of the scale?
a) 1/1200
b) 1/3100
c) 1/3162
d) 1/3200
Explanation: Area of the field = 25,000m2
Area of field on the map = 5cm*5cm = 25cm2
1cm2 = 25000/25 = 1000m2
1 cm = 31.62 m
Now Representative Fraction = 1cm /31.62m = 1/3162.