Percent elongation is best described as

Percent elongation is best described as

• A. A measure of ductility
• B. A measure of hardness
• C. A measure of strength
• D. A measure of toughness

Answer: (A)

Percent elongation shows how much a material can stretch before it breaks, expressed as a percentage of its original length. That stretching before fracture is exactly what ductility describes—the ability of a material to undergo plastic deformation. In a tensile test, you pull the specimen until it fractures, and the increase in length divided by the original length (times 100) gives the percent elongation. Materials with high ductility, like many steels, have higher percent elongation, while brittle materials show little elongation. Hardness relates to resistance to indentation, not how much a material can stretch. Strength is about the maximum stress a material can bear before deforming or failing, not the amount of deformation it can undergo. Toughness combines strength and ductility as the energy absorbed up to fracture, not just elongation. So the description that percent elongation measures ductility is the most accurate.

Percent elongation shows how much a material can stretch before it breaks, expressed as a percentage of its original length. That stretching before fracture is exactly what ductility describes—the ability of a material to undergo plastic deformation. In a tensile test, you pull the specimen until it fractures, and the increase in length divided by the original length (times 100) gives the percent elongation. Materials with high ductility, like many steels, have higher percent elongation, while brittle materials show little elongation.

Hardness relates to resistance to indentation, not how much a material can stretch. Strength is about the maximum stress a material can bear before deforming or failing, not the amount of deformation it can undergo. Toughness combines strength and ductility as the energy absorbed up to fracture, not just elongation. So the description that percent elongation measures ductility is the most accurate.