What is the symbol for a ground connection on a schematic?

The symbol for a ground connection on a schematic is represented by three horizontal lines stacked on top of each other, with each line progressively shorter than the one below it. This design visually conveys the concept of grounding in electrical circuits, where the ground serves as a reference point for voltage levels and a return path for current. The three lines indicate a strong connection to ground, which is crucial for safety and stability in electrical systems.

Other choices are commonly used symbols in schematics but do not represent a ground connection. A single horizontal line typically represents a direct connection or wire, a dot might indicate a junction or connection point, and a wavy line often signifies an earth or ground but is not the standard representation for a ground connection in most schematic conventions. Thus, the three horizontal lines are the correct and widely accepted symbol for indicating a ground connection in electrical schematics.