Oklahoma Locksmith Practice Exam

Which of the following is primarily used to protect circuits from overloads?

1. Capacitor

2. Transformer

3. Fuse

4. Resistor

The correct answer is: Fuse

The fuse is primarily used to protect circuits from overloads by interrupting the flow of electricity when the current exceeds a designated level. When there's an overload, which can arise from a short circuit or excessive current draw, the fuse contains a metal wire or strip that melts due to the heat generated by the excess current. This melting effectively breaks the circuit, preventing further flow of electricity, which could otherwise lead to damage to the circuit or even a fire hazard. This intentional failure mechanism ensures that the downstream components remain safe from high current conditions. In contrast, a capacitor is designed primarily for storing and releasing electrical energy, while a transformer is utilized for changing voltage levels in an AC circuit. A resistor, on the other hand, is used to limit the amount of current flowing in a circuit but does not provide the same level of protection against overloads as a fuse does. Thus, while all these components have important roles, the fuse is specifically engineered to prevent damage due to electrical overloads.