Final answer:
There is no universal numeric symbol for a dryer centrifugal switch; it's usually represented by a circle with an arrow and labeled with 'CS'. Always refer to the diagram's legend for accurate identification.
Step-by-step explanation:
The symbol that represents a dryer centrifugal switch in electrical diagrams can vary depending on the specific schematics or standards being used. However, no typical numeric symbols like 1, 4, 6, or 7 universally represent a centrifugal switch. For accurate identification, it's important to refer to the legend of the specific diagram you're working with since symbols can differ by manufacturer or electrical standards. Generally, a centrifugal switch is depicted as a circle with an arrow illustrating the rotational aspect, often labeled with letters like 'CS' to denote 'centrifugal switch.' Without additional context or a diagram legend, it's not possible to confidently assign the correct symbol only by the numbers given.