An arc is created by a _____ situation whether it is between two or more phases or phase to ground.

• A. Open circuit
• B. Short circuit
• C. Ground fault
• D. Insulation failure

Answer: (B)

Arcing happens when a fault creates a low-impedance path that lets a large current flow between conductors or to ground. That’s exactly what a short circuit does: it bypasses the normal load and connects conductors directly, whether between two phases or from a phase to ground. The sudden surge of current can ionize the air and form a plasma channel, the arc, as the gap conducts. An open circuit wouldn’t produce current or an arc, and insulation failure is a broader failure mode that can lead to arcing but isn’t the specific fault condition described. A ground fault is a type of short to earth, but the general term that covers both phase-to-phase and phase-to-ground faults is short circuit, making it the best fit.