Spring behavior under load: elasticity vs permanent distortion Statement: A spring, when loaded, is permanently distorted and recovers its original shape when the load is removed.

Introduction / Context:
Springs are energy-storing elements designed to operate primarily within the elastic range so that they return to original geometry after unloading. The statement mixes the terms permanently distorted and recovers, which are mutually exclusive in mechanics.

Given Data / Assumptions:

• Conventional helical spring made from spring steel.
• Loading within the design range, not exceeding yield.

Concept / Approach:
Elastic deformation is reversible; plastic deformation is permanent. Properly designed springs operate below yield stress so that deflection is recoverable. Permanent set indicates plasticity, which is not desired in normal service.

Step-by-Step Solution:
If load is within elastic range: no permanent distortion; full recovery occurs.If load exceeds yield: permanent set occurs and complete recovery does not happen.Therefore the statement claiming permanent distortion yet full recovery is internally inconsistent and wrong for normal operation.

Verification / Alternative check:
Design formulas for springs use allowable shear stress below yield with safety factors; fatigue design also ensures stresses remain reversible over cycles.

Why Other Options Are Wrong:
Agree and the conditional variants conflict with elastic design principles. Impact or temperature conditions may change allowable limits, but permanent set still contradicts full recovery.

Common Pitfalls:
Confusing temporary elastic deflection with permanent set; assuming that any large deflection means plastic deformation.

Final Answer:
Disagree