Question

If a plane is perpendicular to vertical and inclined to horizontal plane with 30 degrees then the horizontal trace makes _______ degrees with xy reference.

(a) 30 degrees

(b) 60 degrees

(c) 150 degrees

(d) 90 degrees

I got this question during an online interview.

I'm obligated to ask this question of Projection of Planes Inclined to one of the Reference Plane & Perpendicular to other in chapter Projection of Planes of Engineering Drawing

Answer 1

The correct choice is (d) 90 degrees

For explanation I would say: When a plane is perpendicular to one of the reference planes and inclined to the other, its inclination is shown by an angle which its projection on the plane to which it is perpendicular, makes with xy. And converse for traces.