Difficulty: Easy
Correct Answer: resilience
Explanation:
Introduction / Context:Several energy-based terms are used in strength of materials: strain energy, resilience, proof resilience, and modulus of resilience. Correct identification supports design against shock and fatigue, and informs material selection for energy absorption.
Given Data / Assumptions:
Concept / Approach:Strain energy is the energy stored in a body due to deformation. When this is considered up to the elastic limit, it is called resilience. Proof resilience is specifically the maximum strain energy stored per unit volume up to the elastic limit. Modulus of resilience is that proof resilience expressed per unit volume. Toughness (for comparison) relates to total energy absorption up to fracture (area under the entire stress–strain curve).
Step-by-Step Solution:
Identify the domain: elastic range only.Term for total energy stored in this range: resilience.Differentiate from proof resilience and modulus of resilience: the latter is an energy per unit volume at the elastic limit.Verification / Alternative check:Consulting standard definitions: resilience (overall stored energy within elastic limits), proof resilience (maximum at elastic limit), modulus of resilience (per unit volume measure at elastic limit).
Why Other Options Are Wrong:
Common Pitfalls:Using the terms interchangeably; forgetting the 'per unit volume' qualifier for modulus of resilience; confusing toughness with resilience.
Final Answer:resilience
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