Final answer:
The meaning of electrical symbols in an electrical plan is shown in a C. legend, which is a key to understanding the components represented in a schematic diagram.
Step-by-step explanation:
The document that shows the meaning of electrical symbols used in an electrical plan is known as a legend. A legend provides a visual explanation of the various symbols that appear on a schematic diagram, just like those seen in figure 8.9, which represents various types of capacitors. In electrical diagrams, symbols are used to represent elements such as wires, batteries or voltage sources, resistors, and grounds, as indicated by the thin black lines, red parallel lines, and zigzag symbols.
The accurate understanding of these symbols in a floor plan or schematic is critical for analyzing the electrical components and their function within the system. For instance, Figure 20.8 illustrates a simple electric circuit where the schematic symbol for a battery and a resistor are used, which provides a standardized method of communication for engineers and electricians.