Which statement correctly defines a short circuit?

• A. A break in the circuit that stops current flow.
• B. A circuit with no load causing voltage drop to zero.
• C. Unwanted contact between points at different voltage levels, causing an unintended current path.
• D. A circuit that alternates current direction.

Answer: (C)

A short circuit happens when an unintended, very low-resistance connection forms that bypasses the normal load, so current flows through a path it shouldn’t take. This is why the statement that describes unwanted contact between points at different voltage levels, creating an unintended current path, is the best definition. It captures the essence: a new, direct path that shunts the designed resistance, allowing excessive current to flow.

Think of current as following the easiest route. When a short forms, the path of least resistance bypasses the intended load, which can cause overheating, fuse blows, or tripping breakers. That’s distinct from an open circuit, where the circuit is broken and no current flows; from a situation with no load causing a voltage drop to zero, which isn’t how short circuits are defined; and from a circuit that simply changes direction, which describes alternating current rather than a short.