What is shown by thick, solid lines with arrows in a drawing?

Thick, solid lines with arrows in a drawing indicate cutting or viewing planes. These lines are used to represent the location at which a section view of the object is taken. The arrows point to the direction from which the viewer is looking at the object, clarifying how the cross-section is oriented.

This is crucial in technical drawings because it helps viewers understand the internal features of the object, which may not be visible from the exterior. The use of these lines conveys important information about the dimensional and structural characteristics of the component being depicted, ensuring that there is no ambiguity in how the part should be interpreted or fabricated. It establishes a clear visual communication standard within engineering drawings, which is essential for accurate manufacturing and assembly processes.

Other choices either represent different aspects of drawing conventions or are not used to indicate the same information as cutting or viewing planes. For instance, offset cutting planes have specific forms and uses that differ from the general cutting plane representation; break lines depict a section of an object that has been removed for clarity without showing the details; and leader lines are used to connect labels or notes to specific features in a drawing.