How is the perpendicularity symbol represented?

• A. An upright T
• B. An upside down T
• C. A horizontal line
• D. A circle

Answer: (B)

The symbol for perpendicularity in GD&T is represented by an upside-down T. This graphical representation clearly indicates that a surface or feature must be at a right angle (90 degrees) to a datum or another feature. It is essential for ensuring proper assembly and functionality of parts in relation to one another, allowing for accurate and repeatable measurements. Recognizing the symbol is crucial for understanding and applying tolerance requirements effectively in engineering drawings and specifications.

The other symbols mentioned do not represent perpendicularity. An upright T might suggest something related to symmetry or alignment but does not denote the specific relationship of perpendicularity. A horizontal line could denote a different geometric relationship or feature control but lacks the clarity that denotes angle requirements. A circle typically represents features like holes or points but is not associated with angular tolerances. Understanding the correct representation helps in interpreting technical drawings accurately and ensures that constructions meet prescribed standards.