Surprise quiz-2

What is the sum of the volume fractions of the fiber and matrix in a composite material?

• Less than 1

• Exactly 1

• Greater than 1

• Depends on fiber orientation

Which parameter is used to determine the void content in a composite material?

• Fiber volume fraction and mass fraction
  

• Theoretical and actual density

• Elastic modulus and Poisson’s ratio

• Laminate stacking sequence

Which approach considers the stress-strain relationship of composite materials based on the rule of mixtures?

• Mechanics of materials approach

• Semi-empirical model

• Elasticity approach

• Classical lamination theory

In Classical Lamination Theory (CLT), what assumption is made about the stress in the thickness direction?

• It varies linearly

• It is constant

• It is zero

• It depends on fiber orientation

Which failure criterion is most commonly used for laminated composites?

• Von Mises Criterion

• Maximum Stress Criterion

• Rankine Criterion

• Mohr-Coulomb Criterion

What is the main advantage of sandwich construction?

• Increased weight

• High strength-to-weight ratio

• Increased density

• Reduced stiffness

Which of the following is NOT a typical material used for the core in sandwich construction?

• Honeycomb structures

• Foam cores

• Balsa wood

• Stainless steel

Which of the following is NOT a common failure mode in sandwich panels?

• Face wrinkling

• Core shear failure

• Delamination

• Corrosion failure

What is the primary function of the core in a sandwich panel?

• Provide bending stiffness

• Resist shear forces

• Increase weight

• Reduce thermal conductivity

Which of the following best describes "face wrinkling" failure in sandwich panels?

• The core material crushes under load

• The face sheet buckles due to compressive stress

• The adhesive layer fails

• The core undergoes excessive shear deformation