Engineering Drawing MCQ with answer and solution

Concept

Definition of representative fraction in drawing

Formula

NONE

Step-by-step solution

1. Representative Fraction (RF) represents the scale of a drawing or map as a unitless ratio. 2. It is calculated by dividing the length of an object measured on the drawing by the actual length of the object. 3. Both lengths must be converted to the same unit before taking the ratio. Answer: A

Explanation

Representative fraction is defined as the ratio comparing the dimensions of an object as depicted on a drawing to its actual physical dimensions in real life. Because both lengths are converted into the exact same units of measurement, representative fraction exists as a unitless scale ratio. This allows engineers and draftspersons to scale drawings uniformly regardless of the measurement system used.

Why the other options are wrong

B) Isometric length relates to isometric scale calculations rather than representative fraction. C) This represents the inverse ratio of the representative fraction formula. D) This ratio does not represent the formula for representative fraction.

Shortcut

RF = Drawing length / Actual length (always Map distance over Ground distance).

Common mistake

Inverting the Representative Fraction formula by placing the actual length in the numerator instead of drawing length.