Which of the following properties is impact strength indicative of?
a) Elasticity
b) Hardness
c) Stiffness
d) Toughness
The correct answer and explanation is:
The correct answer is d) Toughness.
Impact strength is a measure of a material’s ability to absorb energy and plastically deform without fracturing when subjected to a sudden force or impact. This property reflects how much energy a material can take before it breaks, which directly relates to toughness.
Explanation:
Impact strength is important in applications where materials are exposed to dynamic or sudden loads, such as in automotive parts, safety helmets, or structural components in buildings. When a material has high impact strength, it means it can withstand shock loads and resist breaking or cracking under rapid stress.
Let’s briefly look at the other options to clarify why toughness is the best fit:
- Elasticity is the ability of a material to return to its original shape after being deformed when the load is removed. While elasticity relates to reversible deformation, impact strength focuses on how much energy a material can absorb before permanent damage or failure, so these two are different concepts.
- Hardness refers to the resistance of a material to surface indentation, scratching, or wear. A hard material is not necessarily tough; for example, glass is hard but brittle and has low impact strength.
- Stiffness measures how much a material resists deformation under load, often quantified by the modulus of elasticity. Stiffness indicates how rigid a material is, but it does not directly describe the material’s capacity to absorb energy without breaking.
- Toughness is the ability to absorb energy and plastically deform before fracturing. It combines strength and ductility. Impact strength is a way to quantify toughness under sudden loading conditions.
In summary, impact strength is best described as an indicator of toughness. It is a critical property for materials used in situations where sudden forces or impacts can occur, ensuring they will not fail catastrophically.