SE 101 UIUC theory quiz 1

Parallel object edges always appear parallel in a parallel projection.

True

In a trimetric projection, none of the angles between the projected principal axes are

equal.

True

Assuming that a projection plane is offset to a new parallel position, an axonometric

projection of an object onto the projection plane will be identical (i.e., same size and

shape) in either location

True

In an isometric drawing, each principal axis is foreshortened by approximately 82% of its

true length.

False

The receding axis angle of an oblique projection is governed by the out-of-plane angle alpha

False

Which of the following is not considered to be a main element of a projection system:

1. 3D object

2. 2D cutting plane

3. Projectors

4. 2D projection plane

5. 2D projected image

2. 2d cutting plane

For the cavalier oblique drawing of the cut block shown in Figure P3-1, which edges are

scalable (i.e. directly measurable)?

1. BC & AC

2. EF & DJ

3. FH & HJ

4. GJ & DJ

5. All of the previous

6. None of the previous

3. FH & HJ

For the isometric drawing of the cut block shown in Figure P3-2, which edges are

scalable (i.e. directly measurable)?

1. BG

2. AG

3. AF

4. DE

5. All of the previous

6. None of the previous

6. None of the previous

Referring to Figure P3-3, if the sight lines are parallel to each other and also

perpendicular to the infinite projection plane, beta = 15˚, and phi = 45˚, what is the type of

projection of the block that will appear on the projection plane?

1. One-point perspective

2. Two-point perspective

3. Trimetric

4. Isometric

5. Dimetric

6. Cabinet oblique

7. Cavalier oblique

8. General oblique

9. None of the previous

5. Dimetric

Referring to Figure P3-3, if the sight lines are perpendicular to the infinite projection

plane, beta = 30˚ and phi = 20˚ initially, which of the following is true of the ratio between the

projected length a' and the actual length a as phi is increased to 70˚?

1. Increases

2. Decreases

3. Does not change

4. Cannot determine without additional information

2. Increases

11. A two-point perspective has two principal axes parallel to the projection plane.

False

Two-point perspective and oblique projections have the same number of principal axes

inclined to the projection plane.

False

In a perspective projection, if the projection plane is located in front of the object, the

projected image will be smaller than the object.

True

When drawn correctly, it is not necessary to erase construction lines.

True

When sketching a straight line, it is important to keep your eye on the pencil as it moves.

False

The most popular lead grade is:

 H

F

2H

HB

B

HB

Which line type is drawn more thickly than the others?

1. Construction

2. Continuous

3. Hidden

4. Center

2. Continuous

9. Trammels can be used for which of the following purposes?

1. Circle construction

2. Proportioning the features of a sketch

3. Transferring dimensions

4. All of the above

5. None of the above

4. All of the above

BIM is enabled by object-based parametric modeling.

True

RFI stands for

Request for Information

In which AEC business method does the owner contract directly with the design-build

team?

1. Design-Bid-Build (DBB)

2. Design-Build (DB)

3. Construction Management at Risk (CM@R)

4. Integrated Project Delivery (IPD)

2. Design-build

In the past 50 years, which of the following is not a reason for increased efficiencies in

manufacturing?

1. Automation

2. Use of information systems

3. Better supply chain management

4. Improved collaboration tools

5. All of the above

6. None of the above

6. None of the above

2D CAD is still common in the construction industry.

True

In BIM, parametric rules do not automatically modify the associated geometries of these

objects

False

In a CAD system, only one layer can be displayed at a time

False

The essential difference between a one and two-point perspective projection is the number of

principal axes parallel to the projection plane.

T

Two-point-perspective and oblique projections have the same number of principal axes

inclined to the projection plane.

False

In parametric solid modeling, the base feature is the feature created directly on the x-y

coordinate plane

F

Edges that are parallel on an object always appear parallel in an axonometric view of the

object.

T

In trimetric drawings, the angles of the principal axes may be chosen independently from the

relative scales along them.

F

If the projection plane is offset (translated) to a new parallel position, an axonometric

projection of an object onto the projection plane will be identical in scale to the previous one.

T

All of the common solid primitives can all be created by sweeping a closed profile.

T

A constructive solid geometry (CSG) solid modeler stores the boundaries of a solid in the

database.

F

. Assembly constraints are used to:

a) Combine part files to create assembly files

b) Manage the relationships between part and assembly files

c) Specify how assemblies should change as parts evolve

d) Specify the placement of parts within an assembly

d) Specify the placement of parts within an assembly

3. (See figure) Consider the Cavalier oblique drawing of a flat-faced block. If edge AB on the

drawing and the actual block are scaled 1:1 (i.e. equal in length), which other edges are

scaled 1:1?

a) HA & GC

b) FC & ED

c) FG & GC

d) EH & GF

e) All of the previous pairs

f) None of the previous pairs

d) EH & GF

Circles parallel to the projection plane will always project onto the projection plane as true

circles in the following cases:

a) Two-point-perspective

b) Cavalier-oblique

c) Dimetric projections

d) All of the previous

e) None of the previous

d) All of the previous

15. (See figure below) Consider the spatial setup for pictorial projection. If the sight lines are

parallel to each other and not perpendicular to the viewplane, beta = 0˚, and phi = 10˚, what is

the type of projection of the block that will appear on the viewplane?

a) Trimetric

b) Isometric

c) Dimetric

d) Cabinet oblique

e) Cavalier oblique

f) General oblique

g) None of the previous

g) None of the previous

6. (See both figures above) If the sight lines are perpendicular to the viewplane, beta = 40˚, and

phi = 35˚ initially, which of the following is true about the scaling variables s1 and s2

relating object edge lengths (projected/actual – see formulas) as phi is increased from 35˚ to

55˚?

a) s1 will decrease and s2 will increase

b) s1 will decrease and s2 will decrease

c) s1 will increase and s2 will decrease

d) s1 will increase and s2 will increase

e) one cannot make a judgment on the previous conditions 1–4 due to insufficient

information

a) s1 will decrease and s2 will increase

(See figure) Consider the isometric pictorial view of a flat-faced block. If edge JA on the

drawing and the actual block are scaled 1:1 (i.e., equal in length), which other edge is scaled

1:1?

a) HE

b) EG

c) GC

d) EC

e) all of the previous

f) none of the previous

f) none of the previous

18. The category of projections termed "axonometric" includes

a) Orthographic drawings of all sorts

b) All orthographic pictorials

c) Trimetric and oblique

d) Trimetric, oblique and perspective

e) Oblique and perspective

f) (None of the previous

b) All orthographic pictorials

9. Which of the following is not a Boolean operation?

a) Union or Join

b) Extrusion

c) Intersection

d) Subtraction or Difference

b) Extrusion

The term wireframe refers to:

a) A type of 3D model

b) A type of 3D display

c) A modeling kernel

d) A prototyping method

e) a and b

f) c and d

e) a and b

Boundary representation (B-rep) solid modelers include the following characteristics:

a) Primitives stored in database

b) Employs a tree structure

c) Vertex information stored in database

d) Surface boundaries defined in database

e) a and b

f) c and d

f) c and d