A wire that is not large enough to carry the electrical current passing through it will:

• A. Overheat
• B. Short-circuit
• C. Trickle current
• D. Fuse

Answer: (A)

When a conductor carries more current than it can safely handle, it heats up. The heat produced in a wire is governed by I^2R: the current squared times the wire’s resistance. A smaller-gauge wire has higher resistance per unit length and a lower ampacity, so the same current causes more heat. If the current exceeds what the insulation and coating can tolerate, the insulation can overheat, degrade, or even fail, posing a fire risk.

A short circuit is a fault where current spikes because there’s a low-resistance path, which is a different situation. A trickle current is a very small current, usually harmless. A fuse is a safety device that interrupts current when overheating or overloading occurs, rather than describing the outcome itself.