Strength of Materials Questions

• Stress–strain curve interpretation: For the portion from O to A on the typical mild-steel stress–strain diagram (straight-line region), does Hooke's law hold good?
• Shear force diagram interpretation: If the SFD between two points is an inclined straight line, what does it indicate about the loading between those points?
• Cantilever beam of length l carrying a uniformly distributed load w per unit length: Does the maximum bending moment occur at the middle of the span?
• Combined plane stress: A body has tensile stresses of 1200 MPa and 600 MPa on mutually perpendicular planes, with a shear stress of 400 MPa on the same planes. What is the maximum in-plane shear stress?
• Strain energy under a gradually applied axial load: Which expression is correct for a linearly elastic body (σ = stress, V = volume, E = Young's modulus)?
• Thin cylindrical shell under internal pressure p: What is the maximum shear stress in terms of diameter d and wall thickness t?
• Mohr’s circle and maximum shear stress\n\nIn strength of materials, Mohr’s circle is a graphical tool to visualize 2D stress states. In this representation, the magnitude of the maximum shear stress at a point is equal to which geometric feature of the circle?
• Section modulus of a rectangular cross-section about its centroidal axis\n\nFor a rectangular section of breadth b and depth d, determine the section modulus about the centroidal axis parallel to b (i.e., the neutral axis through the centroid).
• Uniformly distributed load (UDL) as an equivalent point load\n\nA uniformly distributed load along a span is often replaced by a single equivalent point load at its centroid. This equivalence is valid for reactions and overall moments, but is it valid “for all sorts of calculations”? Choose the correct statement.
• Location of maximum deflection for a simply supported beam with an off-center point load\n\nA simply supported beam of span l carries a single point load W at an intermediate point C (not necessarily at midspan). Where does the maximum deflection occur?
• Definition of Young’s modulus (modulus of elasticity)\n\nChoose the correct definition of Young’s modulus for linear elastic, uniaxial loading.
• Meaning of proof resilience\n\nState whether the following statement is correct: “Proof resilience is the maximum strain energy which can be stored in a body.”
• Typical Poisson’s ratio range for steel\n\nSelect the most commonly accepted range of Poisson’s ratio (ν) for structural steels under small strains.
• Identification of diamond riveting vs. zig-zag riveting\n\nIn a riveted joint, when adjacent rows are staggered so that each rivet lies midway between two rivets of the opposite row, the joint configuration is called:
• Shear stress distribution in a circular shaft under torsion\n\nWhen a circular shaft is subjected to pure torsion, how does the shear stress vary from the center to the outer surface?
• Equating maximum bending and maximum shear stresses in a circular shaft\n\nA circular shaft of diameter D is subjected simultaneously to a bending moment M and a twisting moment T. If the maximum bending stress equals the maximum torsional shear stress, what is the relation between M and T?
• Axial deformation under self-weight vs. equivalent end load:\nFor a uniform vertical bar, how does the elongation caused by its own weight compare with the elongation produced if the same total weight is applied as a single axial load at the free end?
• Elastic constants relationship:\nFor a material with Poisson’s ratio ν = 0.4, what is the ratio of shear modulus to Young’s modulus (G/E)?
• Effect of axial compression (push) on dimensions:\nA rectangular bar of length l, width b, and thickness t is subjected to a compressive axial load P. Which dimensional change is correct (considering Poisson’s effect)?
• Mohr’s circle interpretation:\nIs the maximum shear stress equal to the radius of Mohr’s circle for a plane-stress state?