what is perpendicular symbol
Surface: Perpendicularity is a fairly common symbol that requires the referenced surface or line to be perpendicular or 90Â° from a datum surface or line. Perpendicularity can reference a 2D line, but more commonly it describes the orientation of one surface plane perpendicular to another datum plane.urface: Perpendicularity is a fairly common symbol that requires the referenced surface or line to be perpendicular or 90Â° from a datum surface or line. Perpendicularity can reference a 2D line, but more commonly it describes the orientation of one surface plane perpendicular to another datum plane.