Answer: Stress.
- A Strain
- B Stress
- C Force
- D Energy
Correct answer: B. Stress
Explanation: Since strain is dimensionless, modulus = stress/strain has the same unit as stress, i.e. N/m² or Pa.
A typical stress-strain curve: the initial straight line (Hooke's Law region, slope = Young's modulus) ends at the elastic limit; beyond the yield point, deformation becomes permanent, peaking at the ultimate tensile strength before the wire finally fractures.
Concept context
Stress, strain, Hookes law, and the elastic moduli that describe how solids deform and recover under load.