Suggested Answers for Review Questions
1.
What is meant by true length?
By true size ?
True length and true size can only be expressed when the feature is parallel to one of the regular projection planes.
2.
Why is a true-length line always parallel to an adjacent reference line?
Because they are always at right angles to the projection lines between the views.
3.
If an auxiliary view is drawn from the front view, its depth dimensions would be the same as in what other views?
The top or bottom and left or right side views
4.
Describe one method for transferring depth between views.
One method is using the folding lines for projecting depth measurements. A second method is to use the reference line and transfer measurements based on measurements from the reference line.
5.
What is the difference between a complete auxiliary view and a partial auxiliary view?
Complete auxiliary views show all of the part. Partial auxiliary views show only that information which adds to the description of the part. It is characterized by a break line, to eliminate unnecessary information.
6.
How many auxiliary views are necessary to draw the true size of an inclined plane? Of an oblique plane?
One auxiliary view is required to show the true size of an inclined plane. Two auxiliary views are required to show the true size of an oblique plane.
7.
What is the angle between the reference-plane lines and the direction-of-sight lines?
8.
90 degrees
How is the development of a pyramid similar to the development of a cone?
9.
They are both developed from the radial line method.
When developing a truncated cone or pyramid, why is the complete solid developed first?
To develop true length lines for measuring where the truncated portion of the cone or pyramid will be.
10.
What descriptive geometry techniques are used to determine the intersection points between two solids?
To determine the intersection points between two solids, you generally need to find one of the solids with true shape and size characteristics.

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14.
What is a transition piece?
A transition piece is one that connects two differently shaped, differently sized, or skewed-position openings.
What is a stretchout line?
A stretchout line is used in parallel line developments for cylinders or boxes. The stretchout line distance will be equal to the circumference of the cylinder or the parameter of the box.
Which parts of a development are true size and true shape?
All parts of the development are true size and true shape.
What building trades use developments and intersections?
The sheet metal industry will use developments and intersections for HVAC duct-work and the opening in roof surfaces for flues and stacks.