Stress is defined as force per unit area. The SI unit of force is Newton (N), and the unit of area is square meters (m²). Therefore, the unit of stress is N/m², also known as Pascal (Pa).
Which law states that stress is directly proportional to strain within the elastic limit?
A Newton’s Law
B Hooke’s Law
C Pascal’s Law
D Bernoulli’s Law
Hooke’s Law states that within the elastic limit, stress is directly proportional to strain. Mathematically, it is expressed as σ=Eϵ, where σ is stress, E is the modulus of elasticity, and ϵ is strain.
What is the ratio of lateral strain to axial strain called?
A Modulus of Elasticity
B Bulk Modulus
C Shear Modulus
D Poisson’s Ratio
Poisson’s Ratio is defined as the ratio of lateral strain to axial strain. It is a material property that describes how a material deforms in directions perpendicular to the applied load. For most materials, it ranges between 0 and 0.5.
Which of the following materials exhibits plasticity?
A Glass
B Rubber
C Steel
D Wood
Plasticity is the property of a material to undergo permanent deformation without breaking. Steel exhibits plasticity as it can be deformed plastically under stress, whereas materials like glass and wood are brittle and break without significant deformation.
What is the point called where a material changes from elastic to plastic behavior?
A Fracture Point
B Yield Point
C Ultimate Point
D Breaking Point
The yield point is the stress at which a material begins to deform plastically. Beyond this point, the material will not return to its original shape when the load is removed, marking the transition from elastic to plastic behavior.
What is the term for the ability of a material to absorb energy before fracture?
A Toughness
B Hardness
C Stiffness
D Ductility
Toughness is the ability of a material to absorb energy and plastically deform without fracturing. It is represented by the area under the stress-strain curve and is a measure of a material’s resistance to impact and shock loading.
Which of the following is a measure of material stiffness?
A Modulus of Elasticity
B Poisson’s Ratio
C Shear Modulus
D Bulk Modulus
The modulus of elasticity (Young’s Modulus) is a measure of a material’s stiffness. It quantifies the relationship between stress and strain in the elastic region and indicates how much a material will deform under a given load.
What type of stress is developed due to axial loading?
A Shear Stress
B Tensile Stress
C Compressive Stress
D Both b and c
Axial loading can produce either tensile stress (if the load is stretching the material) or compressive stress (if the load is compressing the material), depending on the direction of the applied force.
Which theory is used to predict the failure of ductile materials?
A Maximum Shear Stress Theory
B Maximum Normal Stress Theory
C Maximum Strain Theory
D Maximum Energy Theory
The Maximum Shear Stress Theory (also known as Tresca’s theory) is used to predict the failure of ductile materials. It states that yielding occurs when the maximum shear stress in a material reaches the shear stress at yield in a uniaxial tension test.
What is the term for the deformation of a material under constant stress over time?
A Fatigue
B Creep
C Fracture
D Hardening
Creep is the gradual deformation of a material under constant stress over time, especially at high temperatures. It is a time-dependent phenomenon and is critical in designing components for high-temperature applications.
What is the shape of the shear force diagram for a uniformly distributed load on a simply supported beam?
A Linear
B Parabolic
C Rectangular
D Triangular
For a uniformly distributed load on a simply supported beam, the shear force diagram is linear. The shear force varies linearly from one end of the beam to the other, with maximum values at the supports.
Which of the following is NOT a type of beam support?
A Fixed Support
B Hinged Support
C Floating Support
D Roller Support
Floating support is not a standard type of beam support. The common types of beam supports are fixed, hinged, and roller supports, which provide different degrees of restraint against movement and rotation.
What is the term for the stress caused by a sudden change in the cross-section of a material?
A Residual Stress
B Thermal Stress
C Stress Concentration
D Shear Stress
Stress concentration occurs when there is a sudden change in the cross-section of a material, such as holes, notches, or sharp corners. This leads to a localized increase in stress, which can significantly affect the material’s strength.
What is the term for the energy stored in a material due to deformation?
A Kinetic Energy
B Thermal Energy
C Potential Energy
D Strain Energy
Strain energy is the energy stored in a material when it is deformed elastically. It is equal to the work done on the material to cause the deformation and is released when the material returns to its original shape.
Which of the following is a measure of a material’s resistance to indentation?
A Toughness
B Hardness
C Stiffness
D Ductility
Hardness is a measure of a material’s resistance to indentation or scratching. It is determined by tests such as the Brinell, Vickers, or Rockwell hardness tests, which measure the depth or size of an indentation made by a specific force.