mechanical properties

Which of the following is NOT a mechanical property of materials?

• Ductility

• Hardness

• Elasticity

• Thermal conductivity

The property that describes a material’s ability to resist plastic deformation is:

• Elasticity

• Hardness

• Ductility

• Toughness

Which property is measured by the slope of the initial linear portion of a stress–strain curve?

• Yield strength

• Young’s modulus

• Ultimate tensile strength

• Resilience

A material fractures without significant plastic deformation. It is classified as:

• Ductile

• Tough

• Brittle

• Hardness

The area under the stress–strain curve represents:

• Toughness

• Hardness

• Yield strength

• Young’s modulus

A specimen with an original cross-sectional area of 200 mm² is subjected to a tensile load of 40 kN. What is the engineering stress?

• 100 MPa

• 150 MPa

• 200 MPa

• 250 MPa

A steel rod has an original gauge length of 100 mm. After fracture, the final gauge length is 125 mm. What is the percentage elongation?

• 15 %

• 20 %

• 25 %

• 30 %

Fatigue failure occurs due to:

• Single sudden load

• Repeated cyclic loading

• High temperature and creep

• Large plastic deformation

Which of the following best describes ductility?

• Ability of a material to resist surface indentation

• Ability of a material to undergo significant plastic deformation before fracture

• Ratio of stress to strain within the elastic limit

• Resistance to crack propagation

A material with a high Young’s modulus (E) is expected to be:

• Very flexible

• Very stiff

• Very ductile

• Very hard