Question

Which among these is not the method of surface development?

(a) Parallel-line development

(b) Radial-line development

(c) Triangulation development

(d) Geometric development

The question was posed to me during an interview for a job.

Asked question is from Development of Surfaces topic in chapter Development of Surfaces, Isometric Projections, Perspective Projections & Transformation of Projections of Civil Engineering Drawing

Answer 1

Correct answer is (d) Geometric development

Explanation: There is nothing like Geometric development. The surface development methods are-

Parallel-line Method: It is used for developing prisms and single curved surfaces like cylinders, in which all the edges/generation of lateral surfaces are parallel in each other.

Radial-line Method: It is employed for pyramids and single curved surfaces like cones in which the apex is taken as centre and the slant edge or generator as radius of its development.

Triangulation Method: It is used for developing transition pieces.

Approximate Method: It is employed for double curved surfaces like spheres, as they are theoretically not possible to develop. The surface of the sphere is developed by approximate method. When the surface is cut by a series of cutting planes, the cut surfaces is called a zone.