CDT Drafting & Design Principles & Techniques 2 — Questions and Answers
Question 1: Which type of line is used to show the boundary of a partial or interrupted view in technical drafting?
- Break line (Correct answer)
- Section line
- Hidden line
- Center line
Correct answer: Break line
Break lines (short or long) indicate that a portion of the object has been removed to save space or reveal interior detail.
Question 2: In geometric construction, which method is used to bisect a given angle?
- Draw arcs from each ray and connect intersection points to the vertex (Correct answer)
- Measure half the angle with a protractor and draw a ray
- Draw a perpendicular from the vertex
- Connect the midpoints of both rays
Correct answer: Draw arcs from each ray and connect intersection points to the vertex
Bisecting an angle with a compass involves drawing equal arcs from each ray, then connecting the arc intersection to the vertex.
Question 3: What does the term 'true shape' mean in descriptive geometry?
- The actual size and shape of a surface as seen in a view parallel to that surface (Correct answer)
- A shape distorted by foreshortening in an auxiliary view
- The scaled-down representation of an object
- The profile view of a revolved solid
Correct answer: The actual size and shape of a surface as seen in a view parallel to that surface
True shape appears in a view where the line of sight is perpendicular to the surface, showing its actual dimensions without foreshortening.
Question 4: Which drafting instrument is specifically designed to draw lines at any angle relative to a straightedge?
- Adjustable triangle (Correct answer)
- T-square
- French curve
- Compass
Correct answer: Adjustable triangle
An adjustable triangle (or drafting machine) allows the drafter to set and lock any angle for drawing inclined lines.
Question 5: In CAD drafting, what is the purpose of a 'layer' system?
- To organize different types of information so they can be controlled independently (Correct answer)
- To add depth shading to 3D models
- To set the paper size for plotting
- To define the coordinate system origin
Correct answer: To organize different types of information so they can be controlled independently
Layers allow drafters to separate elements such as dimensions, annotations, and geometry so each type can be toggled, locked, or plotted independently.
Question 6: A 'runout' in engineering drawing refers to:
- The gradual blend where a curved surface meets a flat surface (Correct answer)
- The total indicator reading of a rotating part
- The extension of a dimension line beyond its limits
- The overhang of a section cut
Correct answer: The gradual blend where a curved surface meets a flat surface
A runout is a drafting convention showing the smooth transition (fillet or round) where a curved feature meets a flat surface.
Question 7: Which of the following best describes the 'flat pattern' or 'development' of a geometric solid?
- The unfolded surface of a 3D shape laid flat (Correct answer)
- A top-view projection of the solid
- A cross-sectional cut through the solid
- A scaled elevation drawing of the solid
Correct answer: The unfolded surface of a 3D shape laid flat
A development (flat pattern) is the unfolded representation of a 3D object's surfaces laid out on a flat plane, used in sheet metal and packaging.
CDT Drafting & Design Principles & Techniques 2
Which type of line is used to show the boundary of a partial or interrupted view in technical drafting?