Q. Which of the following defects occur due to melting or burning away of base metal?
✅ Correct Answer: (A)
undercut
Explanation: undercut is the cardinal sin of welding grasshopper! cutting into the steel with the force of the arc leaves a cut out groove in the weld. if this is not filled back in with filler metal, it leaves a weld defect which is a weak point that can cause the joint to fail. this can cause property damage, injury and even loss of life.