Civil Engineering Drawing Multiple Choice Questions on “Projections on Auxiliary Planes”.
1. The front and top view are sometimes not sufficient to convey all the information regarding the object. Additional views are therefore projected on other planes known as ____
a) auxiliary vertical plane
b) auxiliary inclined plane
c) auxiliary plane
d) horizontal and Vertical plane
2. Auxiliary views cannot be used for the determining ____
a) the true length of a line
b) the point-view of a line
c) the edge-view of a line
d) the apparent size
3. Auxiliary planes are of _______ types.
a) two
b) one
c) three
d) six
Answer: a
Clarification: These are A.V.P (Auxiliary vertical plane) and A.I.P. (Auxiliary inclined plane). Auxiliary vertical plane is perpendicular to the H.P. and inclined to the V.P. projection on an A.V.P. is called auxiliary front plane. Auxiliary inclined plane is perpendicular to the V.P. and inclined to the H.P. projection on an A.I.P. is called auxiliary top view.
4. What are non-parallel and non-intersecting lines called?
a) Spiral lines
b) Parallel lines
c) Skew lines
d) Perpendicular lines
5. The shortest distance between two parallel lines is equal to the length of the perpendicular drawn between them. If its true length is to be measured, then the two given parallel lines should be shown in their _________ views.
a) top
b) front
c) point
d) line
Answer: c
Clarification: If the point views of the lines are required, then first they have to be shown in their true lengths in one of the orthographic views.
If none of the orthographic views show the given lines in their true lengths, an auxiliary plane parallel to the two given lines should be set up to project them in their true lengths on it.
Even the auxiliary view which shows the lines in their true lengths may not show the perpendicular distance between them in true length. Hence another auxiliary plane perpendicular to the two given lines should be set up. Then the lines appear as points on this auxiliary plane and the distance between these point views will be the shortest distance between them.
6. The end projectors of a line AB is 40 mm. The point A is 24 mm above HP and 10 mm in front of VP. Point B is 46 mm above HP and 46 mm in front of VP. What will be the True length of the line?
a) 57 mm
b) 37 mm
c) 50 mm
d) 47 mm
7. Plane appears as foreshortened surface in all the projection planes is known as _________
a) The parallel plane
b) The vertical plane
c) The slant plane
d) The horizontal plane
8. To save space on the drawing or to save time only ___________ view may be drawn.
a) Half auxiliary
b) Full auxiliary
c) Front
d) Top
9. Planes which are inclined to both the reference planes are called __________
a) vertical planes
b) inclined planes
c) horizontal planes
d) oblique planes
Answer: d
Clarification: Oblique projection is a simple type of technical drawing of graphical projection used for producing two-dimensional images of three-dimensional objects. The objects are not in perspective, so they do not correspond to any view of an object that can be obtained in practice, but the technique does yield somewhat convincing and useful images. The plane at which these activity occur refers to as Oblique planes.
10. Auxiliary views tend to make use of ___________ projection.
a) orthographic projection
b) axonometric projection
c) oblique projection
d) isometric projection
Answer: b
Clarification: Axonometric projection is a type of orthographic projection used for creating a pictorial drawing of an object, where the lines of sight are perpendicular to the plane of projection, and the object is rotated around one or more of its axes to reveal multiple sides.
11. In ____________ the direction of viewing is such that two of the three axes of space appear equally foreshortened.
a) orthographic projection
b) trimetric projection
c) dimetric projection
d) isometric projection
Answer: b
Clarification: In dimetric projection, the direction of viewing is such that two of the three axes of space appear equally foreshortened, of which the attendant scale and angles of presentation are determined according to the angle of viewing; the scale of the third direction (vertical) is determined separately. Approximations are common in dimetric drawings.
12. In _________ the parallel projection rays are not perpendicular to the viewing plane as with orthographic projection, but strike the projection plane at an angle other than ninety degrees.
a) isometric projections
b) orthographic projections
c) axonometric projection
d) oblique projections
Answer: d
Clarification: In both orthographic and oblique projection, parallel lines in space appear parallel on the projected image. Because of its simplicity, oblique projection is used exclusively for pictorial purposes rather than for formal, working drawings. In an oblique pictorial drawing, the displayed angles among the axes as well as the foreshortening factors (scale) are arbitrary. The distortion created thereby is usually attenuated by aligning one plane of the imaged object to be parallel with the plane of projection thereby creating a true shape, full-size image of the chosen plane.