You are testing a steel rod in a tensile testing machine. You need to calculate stress, strain, and elongation under load.
Formula Sheet
σ = F/Aε = ΔL/L₀σ = E·ε (Hooke's law)E_steel ≈ 200 GPaWhat is the tensile stress in the rod? (F = 40,000 N, A = 2 cm² = 2×10⁻⁴ m²)
What is the strain in the rod? (E = 200 GPa = 200×10⁹ Pa)
If the rod is 2 m long, what is the elongation ΔL?
Beyond the yield point on a stress-strain curve, the material undergoes: