What term describes a break in a circuit that prevents current flow?

• A. Ground fault
• B. Open circuit
• C. Short circuit
• D. Series circuit

Answer: (B)

Current can flow only when there is a complete loop back to the source. If there’s a break in the path—such as a broken wire, an open switch, or a loose connection—the circuit isn’t closed, so electrons can’t travel all the way around. With no closed path, there is no current, and the load remains inactive. That situation is called an open circuit.

This is different from a short circuit, where a direct, low-resistance path causes a surge of current while the circuit is still closed; and from a ground fault, where current takes an unintended path to ground due to insulation problems. A series circuit simply refers to components arranged in a single path for current, not to a break in the circuit.