LESSON 1 ANSWERS TO SELF TEST EXERCISES
1. In order to avoid conflict and confusion, and lend continuity to drawings, the meaning of a line with certain
characteristics has been standardized and will be the same on any drawing. (para 1-2) (fig 1-2)
2. The outline is a heavyweight unbroken line used for the primary feature of a drawing. (para 1-2,a) (fig 1-2)
3. The arrows projected at 90 degrees to the cutting plane indicate the viewing direction of the section view.
(para 1-2j) (fig 1-2)
4. In orthographic projection, the only lines and surfaces that project in true length and shape are those parallel to
the plane of projection. Any lines perpendicular to the plane of projection will project as dots, and any lines
angled to the plane will project shorter than true length. (para l-4,a (1))
5. A perspective drawing uses either one or two vanishing points. It is not practical because the scale changes
continuously along the receding lines. (para 1-4,b (3))
6. An isometric projection is a drawing where all three object planes form the same angle with the drawing plane
and the amount of foreshortening is the same for all three axes. An isometric drawing is similar to an
isometric projection except that the scale factor is enlarged and lines appear in true length. (para 1-4,b (1))
7. It is standard drafting practice that the front view show the object's most characteristic features. (para 1-4,a
(4))
8. The top view shows width and depth in true length and the right side view shows height and depth in true
length. The true length dimension common to both views is depth only. (para 1-4,a (4))
9. The drawing of a view showing surfaces as if they were parallel to the drawing plane when they, in fact, are
not is called rotation. When this is done, it will be indicated on the drawing. (para 1-5,b)
10. Closely spaced parallel lines of medium thickness are used to mark the surfaces created by the cutting plane.
(para 1-5,e)
11. A section view showing parts of an object as if they are rotated into or out of the cutting plane is an alined
section. (para 1-5,c (7))
12. Contact processes require sensitized paper. Optical copies can be made from opaque originals and are not less
detailed than contact copies. However, contact processes are less expensive and have less distortion. (para 1-
8)
13. Brownline prints and the ozalid process are both positive contact processes. (para 1-8,b (2))
14. Original or intermediate drawings used in contact processes should never be folded, in order to prevent
creases. Creases prevent close contact with the copy paper. (para 1-9,b)
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