# Engineering Drawing Questions and Answers – Basics of Planes

This set of Engineering Drawing Multiple Choice Questions & Answers (MCQs) focuses on “Basics of Planes”.

1. Oblique planes come under ________________
a) planes perpendicular to both reference planes
b) planes perpendicular to one reference plane and inclined to other reference plane
c) planes inclined to both the reference planes
d) planes parallel to one reference plane and perpendicular to other reference plane

Explanation: Planes may be divided into two main types. i. Perpendicular planes and ii. Oblique planes, planes which are held inclined to both the reference planes are called oblique planes, the rest come under perpendicular planes.

2. The planes which are perpendicular to both the reference plane (horizontal and vertical) are visible clearly only if we watched from ___________
a) front view
b) top view
c) side view
d) isometric view

Explanation: As the required plane is perpendicular to both horizontal plane and vertical plane the top view and front view gives a line in projections so only from side which is perpendicular to both the plane as the required plane the object will appear clearly isometric view also will not give vivid picture.

3. A plane is held parallel to horizontal plane in which view we can watch drawing on that plane?
a) Top view
b) Front view
c) Back view
d) Side view

Explanation: If a plane is parallel to one of the reference plane the projection parallel to plane gives the true shape and size as here plane is parallel to horizontal plane the actual shape is watched from a top view.

4. A circle is placed at 20 degrees with vertical the view from top view will be __________
a) line
b) circle
c) ellipse
d) oval

Explanation: If a circle is parallel to one of the reference plane the projection parallel to plane gives the true shape and size but here plane is inclined so circle transformed to ellipse. If observer also inclined along with plane the circle will remain circle only.

5. A square is held 30 degrees with horizontal plane and turned 30 degrees with respect to vertical plane keeping earlier condition constant. The top view will be ________________
a) line
b) square
c) rectangle
d) parallelogram

Explanation: If a square is parallel to one of the reference plane the projection parallel to plane gives the true shape and size as here plane is inclined so square transformed to rectangle and further it turned parallel to observer so no change in shape and size.
Sanfoundry Certification Contest of the Month is Live. 100+ Subjects. Participate Now!

6. A square is held 30 degrees with horizontal plane and turned 30 degrees with respect to vertical plane keeping earlier condition constant. The front view will be _____________
a) line
b) square
c) rectangle
d) parallelogram

Explanation: If a square is parallel to one of the reference plane the projection parallel to plane gives the true shape and size as here plane is inclined so square transformed to rectangle and further it turned inclined in other way which gives parallelogram shape for square.

7. A triangle is placed perpendicular to both the reference planes (horizontal and vertical plane) which of the following statement is true.
a) Front view-line, top view- triangle
b) Front view-triangle, top view- line
c) Front view –line, top view-line
d) Front view-triangle, side view- line

Explanation: The plane which is perpendicular to both the reference planes (horizontal and vertical plane) is called profile plane or picture plane. The planes parallel to these have a top view and front view as straight line.

8. When a plane is perpendicular to both the reference planes, its traces are perpendicular to ______________
a) xy reference line
b) lines on horizontal plane
c) lines on vertical plane
d) lines on given plane

Explanation: When a plane is perpendicular to both the reference planes, its traces are perpendicular to xy reference line and intersect at xy reference line even when the planes are inclined with both reference planes the traces intersect at xy line.

9. A plane perpendicular to vertical plane and inclined to horizontal plane then the vertical trace of that plane will be _____________
a) parallel to horizontal plane
b) perpendicular to horizontal plane
c) parallel to xy reference line
d) inclined to horizontal plane

Explanation: When a plane is perpendicular to one of the reference planes and inclined to the other, its inclination is shown by the angle which its projection on the plane to which it is perpendicular, makes with xy. Its projection on the plane to which it is inclined, is smaller than the plane itself.

10. A plane parallel to vertical plane then which of the following is false statement.
a) vertical trace will not present
b) horizontal trace is parallel to xy
c) front view give true shape and size
d) top view give true shape and size

Explanation: When a plane is parallel to a reference plane, it has no trace on that plane. Its trace on the other reference plane, to which the earlier reference plane is perpendicular, is parallel to xy reference line.

11. When a plane is perpendicular to a reference plane, its projection on that plane shows its true shape and size.
a) True
b) False

Explanation: When a plane is perpendicular to a reference plane, its projection on that plane is a straight line. When a plane is parallel to a reference plane, its projection on that plane shows its true shape and size.

12. The traces of plane are not intersecting at xy reference line then the plane is __________
a) inclined to H.P and perpendicular to V.P
b) parallel to H.P and perpendicular to V.P
c) perpendicular to both reference planes
d) inclined to V.P and perpendicular to H.P

Explanation: When a plane has two traces, they, produced if necessary, intersect in xy except when both are parallel to xy reference line as in case of some oblique planes. And in those some specific are plane parallel to one reference and perpendicular to other.

Sanfoundry Global Education & Learning Series – Engineering Drawing.

To practice all areas of Engineering Drawing, here is complete set of 1000+ Multiple Choice Questions and Answers.