Which term describes solid models that are clear representations of the final part?

• A. Surface modelling
• B. Solid modelling
• C. Projection drawings
• D. Sketches

Answer: (B)

Solid modelling creates a fully defined 3D object with volume, thickness, and true geometry that corresponds to the finished part. This means you can trust its size, shape, and how it would function in an assembly, and you can derive dimensions, tolerances, and even manufacturing data from it. That level of completeness makes it a clear representation of the final part.

Surface modelling, by contrast, captures only the outer skin or surface without guaranteed volume, so it can look right but isn’t guaranteed to describe the finished part’s internal space or mass properties. Projection drawings are 2D views used to communicate size and shape, not to model the full 3D form. Sketches are rough, early concepts with imprecise geometry. Because of that, solid modelling best fits the description of solid models that clearly represent the final part.