Answer: (1 - 2σ_p).
- A (1 - 2σ_p)
- B (1 + 2σ_p)
- C (1 - σ_p)
- D 2σ_p
Correct answer: A. (1 - 2σ_p)
Explanation: For hydrostatic stress on a cube, the volumetric strain works out to ΔV/V = (3σ/Y)(1-2σ_p), connecting bulk modulus B = Y/[3(1-2σ_p)] to Youngs modulus and Poissons ratio.
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.