**Correct Answer: Robert Hook**

**Explanation:** Robert Hooke formulated the law that states that within the elastic limit, the extension of an elastic material is directly proportional to its tension or compression.

**Correct Answer: σ = Εε**

**Explanation:** According to Hook’s law, the stress (σ) in a material is directly proportional to the strain (ε) within the elastic limit, where E is the Young’s modulus of elasticity.

**Correct Answer: non-linear elastic zone**

**Explanation:** The non-linear elastic zone is the region between the elastic limit and the proportional limit where the relationship between stress and strain deviates from being linear.

**Correct Answer: yield stress to working stress**

**Explanation:** The factor of safety, according to the elastic theory of design, is the ratio of the yield stress (the stress at which the material begins to deform plastically) to the working stress (the maximum stress the material can safely withstand).

**Correct Answer: ratio of lateral strain to longitudinal strain**

**Explanation:** Poisson’s ratio is defined as the ratio of the lateral strain to the longitudinal strain in a material subjected to uniaxial loading. It helps determine the material’s deformation behavior under stress.

**Correct Answer: lesser than one**

**Explanation:** Poisson’s ratio is always less than one for common materials. It indicates the degree of lateral contraction that a material undergoes when stretched longitudinally.

**Correct Answer: both (a) and (b) of the above**

**Explanation:** The typical values of Poisson’s ratio are 0.3 for steel and 0.15 for concrete. It may vary for different materials and is an important parameter in understanding their deformation behavior.

**Correct Answer: 0.4**

**Explanation:** The relationship between Poisson’s ratio (ν), Modulus of Rigidity (G), and Young’s Modulus (E) is given by ν = (E/2G) – 1/2. Given ν = 0.25, G/E = 0.4.

**Correct Answer: greater than the ultimate strength**

**Explanation:** The actual breaking stress of a ductile material from a tension test is typically greater than the ultimate strength due to necking that occurs during the test.

**Correct Answer: flexural rigidity**

**Explanation:** The product EI, where E is the Young’s modulus and I is the second moment of area, is known as the flexural rigidity and represents a beam’s resistance to bending.

**Correct Answer: fatigue**

**Explanation:** Fatigue is the phenomenon of reduced material strength caused by repeated cyclic loading and unloading, leading to cracks and ultimately failure under a lower stress level than the material’s ultimate strength.

**Correct Answer: elasticity**

**Explanation:** Elasticity is the property of a material that allows it to return to its original shape and size after the removal of a deforming force, as long as the force is within the material’s elastic limit.

**Correct Answer: that body which recovers its original shape completely after the removal of force**

**Explanation:** A perfectly elastic body is one that fully regains its original shape and size after the removal of the deforming force, without any permanent deformation or energy loss.

**Correct Answer: stiffness**

**Explanation:** Stiffness is the load required to produce a unit deflection in a material or structure. It indicates how resistant a material is to deformation under an applied load.

**Correct Answer: ductility**

**Explanation:** Ductility is the property of a material that allows it to undergo significant plastic deformation under tensile stress without rupture. It is associated with the ability to be drawn into wires.

**Correct Answer: mild steel**

**Explanation:** Mild steel is relatively ductile compared to cast iron, wrought iron, and bronze, as it can undergo significant deformation before fracturing.

**Correct Answer: the ability to absorb energy during plastic deformation**

**Explanation:** Toughness is the ability of a material to absorb energy and deform plastically before fracturing. It represents the area under the material’s stress-strain curve.

**Correct Answer: toughness**

**Explanation:** Impact tests are performed to determine the toughness of a material by measuring the energy absorbed during the fracture of a standard notched specimen under an impact load.

**Correct Answer: malleability**

**Explanation:** Malleability is the property of a material that allows it to be deformed into thin sheets or plates under compressive forces without rupturing. It is essential for processes such as rolling and forging.

**Correct Answer: fatigue of the metal**

**Explanation:** Fatigue of the metal refers to the phenomenon where a material fails at a stress lower than its ultimate stress, typically occurring after repeated applications of reversible tensile or compressive stress.

**Correct Answer: endurance limit**

**Explanation:** The endurance limit is the maximum stress level a material can withstand indefinitely without failing under cyclic loading. It represents the safe threshold below which the material will not fail when subjected to a reversal of stress.

**Correct Answer: coaxing**

**Explanation:** Coaxing is the method of improving the fatigue resistance of a metal by subjecting it to progressively higher stress levels through repeated loading. This process can increase the metal’s endurance limit and prolong its fatigue life.

**Correct Answer: creeping**

**Explanation:** Creep is the phenomenon where materials deform slowly over time under a constant load, particularly under high temperatures. It is a significant factor in the long-term behavior of materials subjected to constant stress.

**Correct Answer: irrecoverable deformation in the body**

**Explanation:** Permanent set refers to the irreversible deformation or strain that remains in a material or structure after the removal of the applied load. It represents the residual deformation even when the load is no longer present.

**Correct Answer: incompressible**

**Explanation:** A Young’s Modulus of zero would imply that the material is perfectly incompressible, meaning that it cannot be compressed or deformed under an applied load.

**Correct Answer: types of material**

**Explanation:** The limit of proportionality, a point on the stress-strain curve, is dependent on the material’s properties and represents the limit beyond which Hooke’s law is no longer applicable.

**Correct Answer: N/m^2 (Pascal)**

**Explanation:** The SI unit of the modulus of elasticity is the pascal (Pa), which is equivalent to one newton per square meter (N/m^2). It represents the ratio of stress to strain in a material under an applied load.

**Correct Answer: strain**

**Explanation:** Strain is a dimensionless quantity that represents the ratio of the change in size or shape of a material to its original size or shape. It is a measure of deformation and has no units.

**Correct Answer: yielding point**

**Explanation:** The yielding point is the stress level at which a material undergoes permanent deformation or elongation without any increase in the applied load. It marks the transition from elastic to plastic behavior.

**Correct Answer: ultimate strength in tension**

**Explanation:** Tenacity is the ultimate strength of a material under tension, representing the maximum stress it can withstand before fracturing. It is an important mechanical property in understanding material behavior under tensile forces.

**Correct Answer: the ratio of linear stress to linear strain**

**Explanation:** Modulus of Elasticity (E) is determined by the ratio of the linear stress to the linear strain within the elastic limit of a material. It represents the material’s stiffness or rigidity.

**Correct Answer: elastic limit**

**Explanation:** Young’s Modulus of elasticity is the ratio of the stress to the strain within the elastic limit of a material. It characterizes the material’s ability to deform elastically in response to an applied force.

**Correct Answer: the ratio of shear stress to shear strain**

**Explanation:** Modulus of Rigidity (G) is determined by the ratio of the shear stress to the shear strain in the elastic range of a material. It characterizes a material’s resistance to shearing forces.

**Correct Answer: the ratio of the normal stress of equal magnitude on all six faces of a solid cube to the volumetric strain**

**Explanation:** Bulk Modulus (K) is determined by the ratio of the normal stress applied equally on all six faces of a solid cube to the resulting volumetric strain. It characterizes a material’s response to uniform changes in pressure.

**Correct Answer: E= 9KN/3K+N**

**Explanation:** The relationship among the modulus of elasticity (E), modulus of rigidity (N), and bulk modulus (K) is given by E = 9KN / 3K + N.

**Correct Answer: rate of change of length**

**Explanation:** Normal strain refers to the change in length per unit length of an object in the direction of the applied force. It is the ratio of the change in length to the original length of the material.

**Correct Answer: change in the angle between planes at right angles**

**Explanation:** Shear strain refers to the deformation that occurs in a material when subjected to parallel forces acting in opposite directions. It represents the change in the angle between the planes originally perpendicular to each other.

_{1}and E

_{2}are the modulus of elasticity of respective material.)

_{1}/E

_{2}

_{1}/E

_{2})

^{2}

_{1}/E

_{2})

^{3}

**Correct Answer: E _{1}/E_{2}**

**Explanation:** The modular ratio of two materials is the ratio of their respective moduli of elasticity (E). It helps in understanding the relative stiffness of the materials when they are combined in a composite structure.

**Correct Answer: will decrease**

**Explanation:** Young’s Modulus generally decreases with an increase in temperature for most materials. This decrease is due to the increased thermal vibration of the material’s atoms, leading to a reduction in stiffness.

**Correct Answer: mild steel**

**Explanation:** Mild steel typically has the highest Young’s Modulus among the given materials. It is known for its high stiffness and ability to withstand considerable stress without significant deformation.

**Correct Answer: energy stored in a body because of being strained**

**Explanation:** Strain energy is the energy stored within a body as a result of deformation or strain. It represents the energy absorbed or stored due to the work done on the material during the process of straining.

**Correct Answer: all of the above**

**Explanation:** Strain energy of a member represents the work done on the member to deform it, resist elongation, and resist shortening. It is a measure of the potential energy stored in a material due to the applied forces and resulting deformations.

**Correct Answer: resilience**

**Explanation:** Resilience is the strain energy stored in a member when it is strained within the elastic limit. It represents the capacity of a material to absorb energy and deform elastically without permanent damage.

**Correct Answer: elastic limit**

**Explanation:** Proof resilience represents the maximum strain energy stored in a material at its elastic limit. It is a measure of the energy absorbed per unit volume up to the point where the material begins to deform plastically.

**Correct Answer: the resistance offered by the material per unit area to a force**

**Explanation:** Stress in a member refers to the resistance offered by the material per unit area to an applied force. It is the force acting on a unit area of the member and is a fundamental parameter in understanding the material’s behavior under loading.

**Correct Answer: supporting end conditions**

**Explanation:** The stress due to temperature change in a member is influenced by the supporting end conditions. Thermal stress arises due to non-uniform temperature changes within a structure, leading to differential expansion or contraction.

**Correct Answer: more than necessary to continue it**

**Explanation:** The stress required to initiate yielding in a material is significantly greater than the stress needed to continue the yielding process. Once yielding begins, the material undergoes plastic deformation at a lower stress level.

**Correct Answer: twice**

**Explanation:** The ratio of the intensity of stress in a suddenly loaded case to that of gradually applied load is two. This implies that the stress developed in a structure due to sudden loading is twice that of the stress resulting from a gradual or slowly applied load.

**Correct Answer: yielding point**

**Explanation:** The yielding point is the stress level at which a material undergoes permanent deformation more rapidly compared to the increase in the applied load. It marks the transition from elastic to plastic deformation.

**Correct Answer: tensile stress**

**Explanation:** Tensile stress is the stress that develops within a body when equal and opposite forces act on it, tending to elongate or stretch it. It represents the internal force per unit area in the direction of the applied force.

**Correct Answer: normal stress**

**Explanation:** The bending moment acting on the plane of an element causes normal stress on the plane. This stress is perpendicular to the plane and is responsible for the normal forces induced within the material.

**Correct Answer: increases more rapidly**

**Explanation:** As the elastic limit is reached, tensile strain increases more rapidly in proportion to the applied stress. This indicates that the material undergoes greater deformation for each incremental increase in stress.

**Correct Answer: 1/3**

**Explanation:** The ratio of elongations of a conical bar due to its own weight to that of a prismatic bar of the same length is 1:3. This ratio indicates the relative difference in elongation between the two types of bars under the influence of their own weight.

**Correct Answer: one that comes due to the self-weight of the object**

**Explanation:** Dead load of a member refers to the weight that is constant and permanent, primarily due to the self-weight of the structural elements and any fixed attachments. It is a crucial consideration in structural engineering.

**Correct Answer: directly proportional**

**Explanation:** Stress in a beam due to simple bending is directly proportional to the distance from the neutral axis. This stress distribution is a fundamental characteristic of the internal forces in a beam subjected to bending.

**Correct Answer: least radius of gyration**

**Explanation:** Compression members tend to buckle in the direction of the least radius of gyration. This is a critical consideration in the design and analysis of structural elements to prevent buckling failures.

**Correct Answer: a fiber in the cross-section depending on configuration**

**Explanation:** The maximum shear stress in a cross-section can occur at any fiber, depending on the configuration of the structure. It is important to consider the specific geometry and loading conditions to determine the location of the maximum shear stress.

**Correct Answer: at the junction of web and flanges**

**Explanation:** In an H section, the maximum shear stress typically occurs at the junction of the web and flanges. This location experiences the highest shear forces and is a critical point in the analysis of the H section under shear loading.

**Correct Answer: infinite**

**Explanation:** If the stress produced by a prismatic bar is equal to the working stress, the area of the cross-section of the prismatic bar theoretically becomes infinite. This signifies that the cross-sectional area needs to be infinitely large to accommodate the given working stress.

**Correct Answer: n:1**

**Explanation:** If all dimensions of a bar are increased in the proportion n:1, the maximum stress produced in the prismatic bar by its own weight will increase in the ratio of n:1. This emphasizes the relationship between dimensional changes and stress variations in a structural member.

**Correct Answer: static load**

**Explanation:** A static load is a type of load where the magnitude and direction of the force do not change with respect to time. It remains constant and does not induce dynamic effects on the structure.

**Correct Answer: 1**

**Explanation:** A hinge on rollers support has one reaction component. It can resist forces in only one specific direction, typically either vertical or horizontal, depending on the specific configuration and loading conditions.

**Correct Answer: 2**

**Explanation:** A hinged end of a general loading can have two reaction components. These components include both a horizontal and a vertical reaction that counteract the external loading applied to the structure.

**Correct Answer: one end fixed and the other free**

**Explanation:** A cantilever beam is supported at one end, typically fixed, while the other end remains free. This configuration allows the beam to transmit load to the support where it is fixed, while the free end can experience deflection under loading.

**Correct Answer: free end**

**Explanation:** A free end permits displacement in any direction and also rotation, enabling the structure to move and rotate freely without any restraint. This end condition allows for greater flexibility in response to external loading.

**Correct Answer: loading with no component in the direction of the beam**

**Explanation:** A beam supported over three rollers lying in the same plane is stable for loading with no component in the direction of the beam. This support configuration allows the beam to experience forces perpendicular to the beam but not in the direction of the beam itself.

**Correct Answer: rigid**

**Explanation:** A material with zero elasticity is considered rigid. Such materials do not undergo deformation under normal loading conditions and exhibit no flexibility or resilience when subjected to external forces.

**Correct Answer: different properties in three perpendicular directions**

**Explanation:** An orthotropic material exhibits different properties in three perpendicular directions. These materials possess distinct material properties in mutually perpendicular planes, enabling varied responses to external forces.

**Correct Answer: isotropic**

**Explanation:** A material with identical properties in all directions is called isotropic. Such materials exhibit uniform behavior and physical properties regardless of the direction in which forces are applied.

**Correct Answer: none of the above**

**Explanation:** An isotropic material does not possess any of the mentioned properties. It refers to a material with uniform physical properties in all directions and exhibits consistent behavior under loading.

**Correct Answer: has a time-dependent stress-strain relation**

**Explanation:** A viscoelastic material demonstrates a time-dependent stress-strain relationship, indicating that its mechanical properties vary with time under the application of stress. It exhibits both viscous and elastic characteristics.

**Correct Answer: a very little plastic zone**

**Explanation:** A brittle material exhibits very little or almost no plastic zone before failure. It is prone to sudden and catastrophic failure without significant deformation or warning.

**Correct Answer: brittle materials**

**Explanation:** The compression test is commonly used for testing the strength and behavior of brittle materials. It helps determine how a material responds to compressive forces and establishes its compressive strength and stress-strain characteristics.

**Correct Answer: fail suddenly**

**Explanation:** A brittle material is characterized by sudden failure without significant deformation or warning. It fails without extensive plastic deformation and often without any noticeable signs of impending failure.

**Correct Answer: have small plastic deformation before failure**

**Explanation:** Brittle materials have low toughness because they exhibit small plastic deformation or no plastic deformation before failure. Their lack of ductility leads to limited energy absorption capacity before fracture occurs.

**Correct Answer: homogeneous**

**Explanation:** A body with similar properties throughout, without any variation or differentiation in its composition or structure, is referred to as homogeneous. It exhibits uniform characteristics and behavior across its entirety.

**Correct Answer: central axis**

**Explanation:** The moment of inertia of an area will be least with respect to the central axis. This axis represents the axis passing through the centroid of the area and is associated with the minimum moment of inertia.

**Correct Answer: radius of gyration**

**Explanation:** The square root of the ratio of the moment of inertia and the cross-sectional area of a member is known as the radius of gyration. It is a crucial parameter used to describe the structural behavior of a member under bending loads.

**Correct Answer: none of the above**

**Explanation:** The radius of gyration of a rectangular section is not directly proportional to any of the mentioned parameters. It is a critical geometric characteristic used to evaluate the resistance of a structural member to buckling under compression.

**Correct Answer: section modulus**

**Explanation:** The beam strongest in flexure will have the maximum section modulus. The section modulus is a critical parameter that measures a beam’s resistance to bending stress and is directly related to its strength and stiffness.

**Correct Answer: bd^3/12**

**Explanation:** The moment of inertia of a rectangular beam bxd is given by the formula bd^3/12, where ‘b’ is the breadth and ‘d’ is the depth of the beam.

**Correct Answer: I = b^4/12**

**Explanation:** The moment of inertia of a square section is calculated using the formula b^4/12, where ‘b’ represents the length of one side of the square.

**Correct Answer: BD^3/3**

**Explanation:** The moment of inertia of a rectangular section (Bx D) about its base is determined using the formula BD^3/3, where ‘B’ is the breadth and ‘D’ is the depth of the section.

**Correct Answer: bh^3/12**

**Explanation:** The moment of inertia of a triangular section b x h about the base is calculated using the formula bh^3/12, where ‘b’ is the base and ‘h’ is the height of the triangle.

**Correct Answer: bh^3/36**

**Explanation:** The moment of inertia of a triangular section b x h about the center of gravity (c-g) is given by the formula bh^3/36, where ‘b’ is the base and ‘h’ is the height of the triangle.

**Correct Answer: >1**

**Explanation:** The ratio of the moment of inertia of a square section to that of a circular section for a given depth is typically greater than 1, suggesting that the square section has a higher moment of inertia compared to the circular section.

**Correct Answer: 4r/3π**

**Explanation:** The center of gravity of a semicircle is positioned 4r/3π above the base AB (diameter). This calculation helps determine the precise location of the center of gravity for a semicircular section.

**Correct Answer: 2r/π**

**Explanation:** The center of gravity (c.g.) of a semi-circular arc is located at a distance of 2r/π from the base of the arc. This characteristic helps understand the distribution of weight in a semi-circular configuration.

**Correct Answer: πd^3/32**

**Explanation:** The section modulus of a circular section about an axis through its center of gravity (C.G.) is represented by the formula πd^3/32, where ‘d’ is the diameter of the circular section.

**Correct Answer: away from the center**

**Explanation:** Centrifugal force acts away from the center of a curve, leading to an outward force that tends to move objects in a curved path away from the center of the curve.

**Correct Answer: mv^2/R**

**Explanation:** Centrifugal force is given by the expression mv^2/R, where ‘m’ represents the mass of the object, ‘v’ denotes its velocity, and ‘R’ signifies the radius of the curve.

**Correct Answer: towards the center of the path**

**Explanation:** Centrifugal force acts away from the center of the path, while centripetal force acts towards the center, serving as the inward force required to keep an object moving along a curved path.

**Correct Answer: perpendicular to the longitudinal axis**

**Explanation:** The shear force in a concrete beam is assumed to act perpendicular to the longitudinal axis, exerting a lateral force that tends to deform or cause shear deformation in the beam.

**Correct Answer: sum of the transverse forces**

**Explanation:** The shear force on a beam is directly proportional to the sum of the transverse forces applied to the beam. It represents the cumulative effect of the transverse forces that tend to cause the beam to shear along its length.

**Correct Answer: shear force**

**Explanation:** The rate of change of bending moment in a beam is equivalent to the shear force acting on the beam. It represents the variation in the internal bending moment along the length of the beam.

**Correct Answer: intensity of load**

**Explanation:** The rate of change of shear force in a beam is referred to as the intensity of the load. It indicates the variation in the shear force along the length of the beam due to the applied loading conditions.

**Correct Answer: minimum**

**Explanation:** The amount of shear force at the maximum bending moment is minimal. At the point of maximum bending moment, the shear force experiences a minimum value, indicating the specific conditions where the beam is most susceptible to bending.

**Correct Answer: support**

**Explanation:** In the case of a simply supported beam subjected to a uniform distributed load (UDL), the maximum shear force occurs at the support locations. This characteristic helps identify the critical points of shear force distribution in such beams.

**Correct Answer: triangle**

**Explanation:** The shear force diagram for a cantilever carrying a uniform distributed load (UDL) over its entire length takes the shape of a triangle. The distribution of the shear force follows a triangular pattern in such scenarios.

**Correct Answer: load curve between these two sections plus concentrated load applied between the sections**

**Explanation:** The difference in the ordinate of the shear force between any two sections is equivalent to the area under the load curve between these two sections, along with the contribution from any concentrated load applied between the sections. This relation helps in understanding the distribution of loads and shear forces along the beam.

## FAQs on Mechanics of Materials & Structures MCQs for Civil Engineers

### ▸ What topics are covered in Mechanics of Materials & Structures MCQs for Civil Engineers?

Topics include stress and strain, bending moments, shear force, torsion, deflection, and material properties. For detailed MCQs, visit gkaim.com.

### ▸ How can I prepare for Mechanics of Materials & Structures exams using MCQs?

Preparation can be done by practicing MCQs, studying detailed explanations, and reviewing key concepts. You can find a variety of MCQs on Mechanics of Materials & Structures at gkaim.com.

### ▸ Where can I find online MCQs for Mechanics of Materials & Structures?

Online MCQs for Mechanics of Materials & Structures are available on educational websites like gkaim.com, which offer a range of questions to help you prepare for exams and interviews.

### ▸ What is the significance of studying Mechanics of Materials in civil engineering?

Studying Mechanics of Materials is crucial for understanding the behavior of different materials under various loads and designing safe structures. Detailed MCQs on this topic can be found at gkaim.com.

### ▸ How can I improve my understanding of structural analysis through MCQs?

Improving your understanding can be achieved by regularly practicing MCQs, analyzing detailed solutions, and studying fundamental principles. Access a variety of structural analysis MCQs at gkaim.com.

### ▸ Are there mock tests available for Mechanics of Materials & Structures?

Yes, mock tests for Mechanics of Materials & Structures are available at gkaim.com. These tests can help you practice and assess your understanding of the subject.

### ▸ What are common questions in Mechanics of Materials & Structures MCQs?

Common questions include those on stress and strain calculations, bending moment diagrams, shear force diagrams, and deflection of beams. Find detailed MCQs at gkaim.com.

### ▸ How can I use Mechanics of Materials MCQs to prepare for competitive exams?

You can use Mechanics of Materials MCQs to practice problem-solving, understand key concepts, and review detailed solutions. Visit gkaim.com for comprehensive MCQs and quizzes.

### ▸ What resources are best for studying Mechanics of Materials & Structures MCQs?

The best resources include textbooks, online quizzes, and practice MCQs available at gkaim.com. These resources provide in-depth coverage of the subject.

### ▸ How important is the study of deflection in Mechanics of Materials?

The study of deflection is crucial for ensuring the stability and safety of structures. Detailed MCQs on deflection and other key topics are available at gkaim.com.