The strain energy stored in a spring when subjected to the greatest load without being permanently distorted is called:
Try it first: pick an option, then read the explanation.
Correct answer: B. proof resilience
Asked in SSC JE 22/01/2018 (Evening)
Detailed Explanation
Strain energy in a spring is the area under its load–deflection line, ½Wδ.
Why “proof resilience” Is Correct
The energy stored at the proof load is the proof resilience.
| Term | Meaning |
|---|---|
| Stiffness k | Load per unit deflection, k = W/δ |
| Proof load | Greatest load the spring can carry without permanent distortion |
| Proof stress | Maximum stress in the wire at the proof load |
| Proof resilience | Strain energy stored at the proof load, U = ½Wδ |
Why the Other Options Are Wrong
- A. stiffness: Stiffness is W/δ.
- C. proof stress: Proof stress is a stress, not an energy.
- D. proof load: Proof load is a load, not an energy.
Key Point
Proof resilience = ½ × proof load × deflection at proof load.
Key Concepts for Students
- For a close coil, U = (τ²/4G) × wire volume.
- Springs are designed to store energy.
- Modulus of resilience = σ²/2E per unit volume.
Practice more: this is question 11 in Spring MCQs – Part 1. Try the whole set and check every answer instantly.