In arc welding, which electrical quantity must be sufficient to bridge the gap between electrode and workpiece?

• A. Amperage
• B. Voltage
• C. Capacitance
• D. Inductance

Answer: (B)

Voltage must be sufficient to bridge the electrode-workpiece gap by ionizing the air and forming a conductive path. The arc starts when the voltage across that small gap is high enough to overcome the air’s insulating strength, creating plasma so current can flow. Once the arc is established, the current (amperage) controls the heat and metal deposition, and the arc voltage settles at a lower level. Capacitance and inductance affect how the circuit reacts to changes and can influence arc stability, but they don’t provide the necessary bridge across the gap the way adequate voltage does.