In a tensile test, when the material is stressed beyond the elastic limit, the tensile strain ______ compared with the stress.
Try it first: pick an option, then read the explanation.
Correct answer: D. increases more quickly
Asked in SSC JE 03/03/2017 (Morning)
Detailed Explanation
Within the elastic limit, strain is proportional to stress. Beyond it, the material deforms plastically and the stress–strain curve flattens.
Why “increases more quickly” Is Correct
Past the elastic limit, a small increase in stress produces a large increase in strain, so the tensile strain increases more quickly than the stress. At yield, strain increases with almost no increase in stress.
Why the Other Options Are Wrong
- A. decreases slowly: Strain never decreases under increasing tensile load.
- B. increases slowly: It increases quickly, not slowly, relative to stress.
- C. decreases more quickly: Strain does not decrease.
Key Point
Beyond the elastic limit: strain increases faster than stress (plastic flow).
Key Concepts for Students
- Slope of the elastic part = E.
- Yield plateau in mild steel: strain grows at almost constant stress.
- Necking begins after the ultimate stress.
Practice more: this is question 30 in Principal Stress and Principal Planes MCQs – Part 2. Try the whole set and check every answer instantly.