Question

Scales having same representative fraction but graduated to read different units are called ______________________

(a) Scale of chords

(b) Circular vernier scale

(c) Comparative scale

(d) Diagonal scale

This question was posed to me in an international level competition.

This intriguing question originated from Types of Scales topic in section Scales of Engineering Drawing

Answer 1

The correct answer is (c) Comparative scale

To explain I would say: A drawing drawn with a scale reading inch units can be read in metric units by means of a metric comparative scale, constructed with a same representative fraction. The comparative scales may be plain scales or diagonal scales and may be constructed separately or one above the other.