In a welding circuit, amperage is responsible for weld penetration.

• A. False
• B. True
• C. Not applicable
• D. Not sure

Answer: (B)

Amperage controls heat input in the weld arc, which sets how deeply the weld penetrates. When you increase current, more heat is delivered to the weld zone, melting more base metal and allowing the weld pool to fuse deeper into the joint. Lower current reduces heat and results in shallower penetration. While voltage, travel speed, and joint setup also affect the arc and fusion, the direct relationship is that higher amperage yields greater penetration. So the statement is true. The other options don’t fit because they deny or ignore the clear link between current and penetration.