Question

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

This question was addressed to me during an interview.

My question is from Basics of Planes in chapter Projection of Planes of Engineering Drawing

Answer 1

Right answer is (a) xy reference line

For explanation I would say: 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.