Structures · MCQ practice Stress and Strain MCQs – Part 2
15 questions. Tap an option to check it instantly, then read the solution.
Part 2 of 3 Question 16 Easy
A 1 m long steel rod of cross-section 20 mm × 20 mm carries a tensile force of 40 kN. Find the elongation if E = 200 GPa.
A 0.005 mm B 0.5 mm C 5 mm D 50 mm
Answer: B. 0.5 mm
δ = PL/AE = 40000 × 1000/(400 × 200000) = 0.5 mm.
Question 17 Medium
In a composite system subjected to a temperature rise, with its ends constrained to remain together, the component with the lower coefficient of linear expansion will experience:
A Tensile stress B Compressive stress C Tensile or compressive stress depending on the loading D Zero stress
Answer: A. Tensile stress
The low-α component is stretched by the high-α component: tension. The high-α component is held back: compression.
Question 18 Easy
The ratio of the stress induced by a suddenly applied axial load to that induced by the same load applied gradually is:
A 1.5 B 2.5 C 2 D 3
Answer: C. 2
Sudden: σ = 2P/A; gradual: σ = P/A. Ratio = 2.
Question 19 Easy
Shear modulus of elasticity is the ratio of:
A tensile stress and strain B compressive stress and strain C bending stress and strain D shear stress and shear strain
Answer: D. shear stress and shear strain
G = shear stress ÷ shear strain.
Question 20 Easy
A linear force–deformation relation is obtained in materials:
A having elastic stress–strain property B having plastic stress–strain property C following Hooke's law D which are rigid elastic materials
Answer: C. following Hooke's law
Hooke's law (stress ∝ strain) is what makes force proportional to deformation.
Question 21 Medium
Which statement is true? A. Impact load equals the sum of the load actually caused and the load had it been a dead load. B. Impact load equals the difference between these two.
A Only A B Only B C Both A and B D Neither A nor B
Answer: B. Only B
Impact load is the extra load caused by dynamic action: (actual dynamic load) − (same load as static).
Question 22 Medium
Poisson's ratio μ is defined as the ratio of:
A axial strain to transverse strain B axial strain to shear strain C shear strain to axial strain D None of these
Answer: D. None of these
μ = transverse (lateral) strain ÷ axial strain. Option (a) is inverted, so the answer is (d).
Question 23 Medium
Identify the correct statement.
A Hooke's law is valid up to the elastic limit B Hooke's law is valid up to the yield point C Hooke's law is valid up to the limit of proportionality D Hooke's law is valid up to the last point
Answer: C. Hooke's law is valid up to the limit of proportionality
Stress is proportional to strain only up to the limit of proportionality. (The revised key did not accept a single option; see the note.)
Question 24 Medium
For an isotropic, homogeneous and elastic material obeying Hooke's law, the number of independent elastic constants is:
A 3 B 1 C 9 D None of these
Answer: D. None of these
Only 2 of E, G, K and μ are independent; 2 is not listed, so (d).
Question 25 Easy
Which statement is true?
A Limit of proportionality depends on area of cross-section B Limit of proportionality depends on type of loading C Limit of proportionality depends on type of material D All options are correct
Answer: C. Limit of proportionality depends on type of material
The limit of proportionality is a stress value — a property of the material.
Question 26 Easy
Which statement is true?
A The ability of a material to absorb energy until rupture is known as hardness B The ability of a material to absorb energy until rupture is known as toughness C The ability of a material to absorb energy until rupture is known as brittleness D None of these
Answer: B. The ability of a material to absorb energy until rupture is known as toughness
Energy absorbed up to fracture = toughness (area under the whole stress–strain curve).
Question 27 Easy
A rod of uniform cross-section A and length L elongates by δ under an axial force P. Young's modulus E is: (i) Pδ/AL (ii) Aδ/PL (iii) PL/Aδ (iv) PA/Lδ
A (i) only B (ii) only C (iii) only D (iv) only
Answer: C. (iii) only
E = (P/A)/(δ/L) = PL/(Aδ).
Question 28 Medium
A composite beam is made of two equal strips, one brass and one steel. If the temperature is raised:
A steel experiences a tensile force B brass experiences a compressive force C the composite beam is subjected to a couple D All of these
Answer: D. All of these
Brass (higher α) is held back → compression; steel → tension; the two equal, opposite, offset forces form a couple that bends the strip.
Question 29 Easy
A linear force–deformation relation is obtained in materials:
A having elastic stress–strain property B having plastic stress–strain property C which are rigid elastic materials D None of these
Answer: A. having elastic stress–strain property
Among these options, the elastic (linear elastic, Hookean) material gives a linear force–deformation relation.
Question 30 Easy
If a material has identical properties in all directions, it is said to be:
A homogeneous B elastic C isotropic D None of these
Answer: C. isotropic
Same properties in every direction = isotropic.
Part 2 of 3