What are the three main elastic constants mentioned?

• Young's modulus, shear modulus, and bulk modulus

• Tensile strength, compressive strength, and shear strength

• Stress, strain, and deformation

• Elasticity, plasticity, and ductility

What does the stress-strain curve from a tensile test show?

• The relationship between temperature and material expansion

• The amount of deformation at various stress levels

• The change in volume under pressure

• The durability of a material under cyclic loading

What is the significance of the elastic region in the stress-strain curve?

• It shows the material will not return to its original shape

• It indicates permanent deformation

• It represents reversible deformation

• It is where the material fractures

What is Young's modulus a measure of?

• Material hardness

• Material strength

• Material toughness

• Material stiffness

What does a higher Young's modulus indicate about a material?

• It is more ductile

• It is less dense

• It is stiffer

• It has higher thermal conductivity

How does the value of Young's modulus vary among materials?

• It is higher for polymers than for metals

• It varies, being highest for ceramics and lowest for polymers

• It is only applicable to metallic materials

• It is the same for all materials

Why do polymers have a lower Young's modulus compared to metals and ceramics?

• Because they are more ductile

• Due to their weaker inter-molecular bonds

• Because of their stronger atomic bonds

• Due to their higher density

Why do alloyed metals have similar Young's modulus values despite different mechanical properties?

• Because of their similar atomic structures

• Due to the small percentage of alloying elements

• Due to their identical crystalline structures

• Because of the similar inter-atomic bond strength

What role does Young's modulus play in engineering design?

• Determines the color of the material

• Influences the electrical conductivity

• Determines the thermal expansion

• Helps in minimizing elastic deformations

Why is Young's modulus important in the material selection process for a bridge?

• To make the bridge resistant to high temperatures

• To ensure the bridge can conduct electricity

• To minimize elastic deformations under load

• To ensure the bridge has the right color