Question

A line of length 25 cm at first lied on the profile plane parallel to horizontal plane and then keeping one of its ends fixed turned 55 degrees with respect to horizontal plane and then turned 65 degrees with respect to profile plane. What is the length of the line in top view?

(a) 22.65 cm

(b) 10.56 cm

(c) 14.33 cm

(d) 20.47 cm

The question was posed to me during an internship interview.

This intriguing question originated from Projection of Line Inclined to both the Planes in division Projection of Lines of Engineering Drawing

Answer 1

Right choice is (c) 14.33 cm

The explanation: First imagine the line in profile plane parallel to vertical plane as here we are asked to find the side view’s length so even if the line is rotated within the horizontal plane the line length will not change and also rotated with respect to the horizontal plane which is calculated as follows  25 x cos (55)= 14.33 cm.