Which of the following is a common sign of a damaged circuit?

A common sign of a damaged circuit is the presence of visible burnt or melted components. This indication suggests that excessive current has flowed through parts of the circuit, often resulting in overheating. Such damage may be caused by short circuits, which create low resistance pathways, leading to a surge in current. When components like resistors, capacitors, or circuit boards experience this increased current, they can overheat and ultimately burn out, leaving physical evidence of damage.

This visibility of damage can help technicians quickly identify problematic areas within the circuit, allowing for more effective troubleshooting and repair. In contrast, stable voltage readings, no change in resistance, and consistent continuity generally indicate a circuit in good working order, making them less indicative of damage.