Material Science Quiz PDF

**Which one of the following is NOT a defined material main property?** - a\) Elastic - b\) Conductive - c\) Plastic - d\) Magnetic\ **Answer:** b) Conductive **Name the ability of metal to extend without losing strength or breaking.** - a\) Elasticity - b\) Ductility - c\)...

**Which one of the following is NOT a defined material main property?** - a\) Elastic - b\) Conductive - c\) Plastic - d\) Magnetic\ **Answer:** b) Conductive **Name the ability of metal to extend without losing strength or breaking.** - a\) Elasticity - b\) Ductility - c\) Toughness - d\) Hardness\ **Answer:** b) Ductility **Which material has less resistance to fracture?** - a\) Metals - b\) Polymers - c\) Ceramics - d\) Concrete\ **Answer:** d) Concrete **Which one of the following is NOT defined under advanced materials?** - a\) Nanomaterials - b\) Biomaterials - c\) Micromaterials - d\) Smart materials\ **Answer:** c) Micromaterials **Which one of the following groups is less stiff than others?** - a\) Metals - b\) Polymers - c\) Ceramics - d\) Composites\ **Answer:** b) Polymers **Which group of material is a better conductor?** - a\) Metals - b\) Polymers - c\) Ceramics - d\) Composites\ **Answer:** a) Metals **Which one of the following composite materials is stiffer and stronger?** - a\) Glass fiber reinforced - b\) Carbon fiber reinforced - c\) Aramid fiber reinforced - d\) Ceramic matrix composites\ **Answer:** b) Carbon fiber reinforced **Which one of the following cannot be a solution to prevent crack propagation?** - a\) Heat treatment - b\) Stress relieving - c\) Rounding the hatch corners - d\) Material substitution\ **Answer:** c) Rounding the hatch corners **What causes ductile metal alloys to become brittle?** - a\) High temperature exposure - b\) Cooled to very low temperatures - c\) Excessive deformation - d\) Corrosion\ **Answer:** b) Cooled to very low temperatures **If the applied strength is 100 MPa and yield strength is 200 MPa, what is the design factor?** - a\) 0.5 - b\) 1 - c\) 2 - d\) 4\ **Answer:** c) 2 **Which property is the measure of the degree of plastic deformation sustained at fracture?** - a\) Toughness - b\) Ductility - c\) Resilience - d\) Hardness\ **Answer:** b) Ductility **What is the average tensile strength for these three samples: 200 MPa, 210 MPa, 220 MPa?** - a\) 200 MPa - b\) 210 MPa - c\) 220 MPa - d\) 215 MPa\ **Answer:** b) 210 MPa **Before the yield point, the deformation is?** - a\) Elastic - b\) Plastic - c\) Brittle - d\) Ductile\ **Answer:** a) Elastic **If the loading is removed before the yield strength, what happens to the strain?** - a\) Strain increases - b\) Strain becomes zero - c\) Strain decreases slightly - d\) Strain remains constant\ **Answer:** b) Strain becomes zero **The maximum stress that can be experienced by a structure/material is?** - a\) Yield strength - b\) Tensile strength - c\) Shear strength - d\) Compressive strength\ **Answer:** b) Tensile strength **Hooke's law can be implemented?** - a\) After the yield point - b\) Before the yield point - c\) At failure - d\) During fracture\ **Answer:** b) Before the yield point **What is the formula of stress?** - a\) Stress = Force × Area - b\) Stress = Force / Area - c\) Stress = Area / Force - d\) Stress = Force × Velocity\ **Answer:** b) Stress = Force / Area **What is the unit of stress?** - a\) Newton - b\) Pascal - c\) Megapascal (MPa) - d\) Joule\ **Answer:** c) Megapascal (MPa) **The units of yield strength are?** - a\) N or J - b\) psi or N/m² - c\) MPa or psi - d\) Pa or Joule\ **Answer:** c) MPa or psi **The capacity of a material to absorb energy when deformed elastically and recover this energy upon unloading is known as?** - a\) Toughness - b\) Resilience - c\) Hardness - d\) Ductility\ **Answer:** b) Resilience 21. **What is the unit of strain?** - a\) Megapascal (MPa) - b\) Joule - c\) It has no units - d\) Newton\ **Answer:** c) It has no units 22. **What is the strain offset when a straight line is constructed parallel to the elastic portion of the stress-strain curve?** - a\) 0.001 - b\) 0.002 - c\) 0.005 - d\) 0.01\ **Answer:** b) 0.002 23. **Modulus of elasticity is given by?** - a\) E = strain / stress - b\) E = force × displacement - c\) E = stress / strain - d\) E = strain² × stress\ **Answer:** c) E = stress / strain 24. **A metal that experiences very little or no plastic deformation upon fracture is termed as?** - a\) Ductile - b\) Elastic - c\) Brittle - d\) Tough\ **Answer:** c) Brittle 25. **What is the purpose of adding a catalyst or hardener to the composite?** - a\) Strengthens the composite - b\) Increases flexibility - c\) Starts the cross-linking process and sets the composite - d\) Increases weight\ **Answer:** c) Starts the cross-linking process and sets the composite 26. **The properties of a composite are highly?** - a\) Isotropic - b\) Homogeneous - c\) Anisotropic - d\) Uniform\ **Answer:** c) Anisotropic 27. **Which of the following matrices has better bonding characteristics with the fiber?** - a\) Epoxy - b\) Polyester - c\) Vinylester - d\) Polypropylene\ **Answer:** a) Epoxy 28. **Carbon fiber can be identified by?** - a\) Transparent appearance - b\) White color - c\) Black color - d\) Silver shine\ **Answer:** c) Black color 29. **The phase of the composite that is continuous and surrounds the other phase is known as?** - a\) Fiber - b\) Dispersed phase - c\) Matrix - d\) Particle\ **Answer:** c) Matrix 30. **In cross-ply composite laminate, the directions of the fiber are:** - a\) Random - b\) 0 degrees and 90 degrees - c\) Both 45 degrees - d\) 0 degrees only\ **Answer:** b) 0 degrees and 90 degrees 31. **In iso-strain condition, the strain of the:** - a\) Matrix and fiber are the same - b\) Matrix is higher than the fiber - c\) Fiber is higher than the matrix - d\) Both are zero\ **Answer:** a) Matrix and fiber are the same 32. **Concrete is an example of?** - a\) Fiber-reinforced composite - b\) Polymer composite - c\) Particle-reinforced composite - d\) Ceramic composite\ **Answer:** c) Particle-reinforced composite 33. **Fibers and particles in the composites are known as?** - a\) Matrix - b\) Continuous phase - c\) Dispersed phase - d\) Secondary phase\ **Answer:** c) Dispersed phase 34. **Which of the following types of composite has the best impact resistance characteristics?** - a\) Carbon fiber reinforced composites - b\) Glass fiber reinforced composites - c\) Aramid fiber reinforced composites - d\) Particle-reinforced composites\ **Answer:** c) Aramid fiber reinforced composites 35. **For dispersion-strengthened composites, particles are normally with diameters between:** - a\) 1 μm -- 10 μm - b\) 0.01 μm -- 0.1 μm - c\) 10 μm -- 100 μm - d\) 0.1 μm -- 1 μm\ **Answer:** b) 0.01 μm -- 0.1 μm 36. **The critical length of the fiber is dependent on?** - a\) Matrix type - b\) Fiber diameter - c\) Temperature - d\) Applied load\ **Answer:** b) Fiber diameter 37. **In uni-directional laminate, all the fibers are arranged in?** - a\) Random directions - b\) 45 degrees only - c\) Either 0 degrees or 90 degrees - d\) Circular pattern\ **Answer:** c) Either 0 degrees or 90 degrees 38. **The longitudinal load along the composite results in?** - a\) Iso-stress - b\) Iso-strain - c\) Failure - d\) Elastic deformation\ **Answer:** b) Iso-strain 39. **Fuselage is assumed to be a?** - a\) Rigid body - b\) Thin-walled structure - c\) Isotropic material - d\) Solid structure\ **Answer:** b) Thin-walled structure 40. **The internal shear forces are?** - a\) Perpendicular to the plane - b\) Parallel to the plane - c\) Distributed uniformly - d\) Negligible\ **Answer:** b) Parallel to the plane 41. **Resultant stress is a combination of?** - a\) Shear stress and normal stress - b\) Tensile stress and compressive stress - c\) Yield stress and tensile stress - d\) Elastic stress and plastic stress\ **Answer:** a) Shear stress and normal stress 42. **The stress that acts along the length of the fuselage is known as?** - a\) Shear stress - b\) Hoop stress - c\) Longitudinal (Axial) stress - d\) Bending stress\ **Answer:** c) Longitudinal (Axial) stress 43. **For brittle materials, which stress is used to predict failure?** - a\) Yield stress - b\) Shear stress - c\) Ultimate stress - d\) Fatigue stress\ **Answer:** c) Ultimate stress 44. **In plane stress problems, the thickness of the material is assumed as?** - a\) Very large - b\) Infinite - c\) Zero - d\) Negligible\ **Answer:** c) Zero 45. **If the number of unknowns is less than the number of equations, then the problem is?** - a\) Statically determinate - b\) Statically indeterminate - c\) Kinematically determinate - d\) Dynamically determinate\ **Answer:** a) Statically determinate 46. **In plane strain problems:** - a\) The strain is in all directions - b\) The strain is in one plane - c\) The strain is zero - d\) The strain is negligible\ **Answer:** b) The strain is in one plane 47. **Von Mises stress criterion is used for?** - a\) Brittle materials - b\) Ductile materials - c\) Composite materials - d\) Ceramic materials\ **Answer:** b) Ductile materials 48. **Most aircraft structural components are fabricated from thin metal sheets so that stresses across the thickness of the sheet are usually?** - a\) High - b\) Uniform - c\) Negligible - d\) Isotropic\ **Answer:** c) Negligible 49. **For principal stresses, the shear stress is assumed?** - a\) Zero - b\) Maximum - c\) Minimum - d\) Constant\ **Answer:** a) Zero 50. **In reaction to the applied force on a beam, the internal normal forces?** - a\) Produce a net moment - b\) Produce a net shear force - c\) Cancel each other - d\) Increase the cross-sectional area\ **Answer:** a) Produce a net moment 51. **Which one of the following structures has less packing factor?** - a\) Face-Centered Cubic - b\) Hexagonal Close-Packed - c\) Body-Centered Cubic - d\) Simple Cubic\ **Answer:** c) Body-Centered Cubic 52. **A homogeneous portion of a system that has uniform physical and chemical characteristics is known as?** - a\) Grain - b\) Phase - c\) Microstructure - d\) Composite\ **Answer:** b) Phase 53. **Does the rate of cooling have an effect on material strength?** - a\) No effect - b\) Weakens the material - c\) Makes the material stronger - d\) Causes plastic deformation\ **Answer:** c) Makes the material stronger 54. **Piezoelectric ceramics are a good example of which advanced material category?** - a\) Nanomaterials - b\) Biomaterials - c\) Smart materials - d\) Composites\ **Answer:** c) Smart materials 55. **The structural elements that are subject to direct observation using some type of microscope are known as?** - a\) Macrostructure - b\) Grain structure - c\) Microstructure - d\) Atomic structure\ **Answer:** c) Microstructure 56. **When the rate of approach to equilibrium is extremely slow, it is known as?** - a\) Stable state - b\) Unstable state - c\) Metastable state - d\) Dynamic state\ **Answer:** c) Metastable state 57. **What is the carbon content in low-carbon steel?** - a\) Less than 0.3% - b\) 0.3% to 0.6% - c\) 0.6% to 1.0% - d\) Greater than 1.0%\ **Answer:** a) Less than 0.3% 58. **Free energy is a function of the?** - a\) Temperature - b\) Pressure - c\) Internal energy - d\) Volume\ **Answer:** c) Internal energy 59. **A single-phase system is termed as?** - a\) Heterogeneous - b\) Homogeneous - c\) Composite - d\) Isotropic\ **Answer:** b) Homogeneous 60. **After the yield point, the deformation is?** - a\) Elastic - b\) Plastic - c\) Brittle - d\) Isotropic\ **Answer:** b) Plastic 61. **The design stress that can be experienced by a structure/material is?** - a\) Tensile strength - b\) Yield strength - c\) Shear strength - d\) Compressive strength\ **Answer:** b) Yield strength 62. **Edge dislocation is a type of?** - a\) Point defect - b\) Planar defect - c\) Linear defect - d\) Volume defect\ **Answer:** c) Linear defect 63. **The study that relates deformation to an applied load or force is known as?** - a\) Physical properties - b\) Mechanical properties - c\) Thermal properties - d\) Electrical properties\ **Answer:** b) Mechanical properties 64. **The property related to changes in temperature or temperature gradients across a material is known as?** - a\) Mechanical properties - b\) Electrical properties - c\) Thermal properties - d\) Optical properties\ **Answer:** c) Thermal properties 65. **Which element has a higher percentage in stainless steel?** - a\) Carbon - b\) Nickel - c\) Iron - d\) Chromium\ **Answer:** c) Iron 66. **When the solution is not capable of dissolving any more solute, it is known as?** - a\) Saturation point - b\) Solubility limit - c\) Equilibrium state - d\) Dynamic state\ **Answer:** b) Solubility limit 67. **Materials have less resistance to fracture?** - a\) Metals - b\) Polymers - c\) Concrete - d\) Ceramics\ **Answer:** c) Concrete 68. **A system is at equilibrium if its free energy is at?** - a\) Maximum - b\) Minimum - c\) Constant - d\) Infinite\ **Answer:** b) Minimum 69. **The property of a material having the same physical properties in all directions is known as?** - a\) Anisotropy - b\) Isotropy - c\) Homogeneity - d\) Elasticity\ **Answer:** b) Isotropy 70. **The measure of material resistance to localized plastic deformation is known as?** - a\) Toughness - b\) Ductility - c\) Hardness - d\) Resilience\ **Answer:** c) Hardness 71. **What is the effect of rolling on material?** - a\) It increases ductility - b\) It will reduce the ductility - c\) It has no effect on the ductility - d\) It reduces strength\ **Answer:** b) It will reduce the ductility 72. **The smaller the grain size, the \_\_\_\_\_\_\_\_ the material will be.** - a\) Weaker - b\) Stronger - c\) Softer - d\) More ductile\ **Answer:** b) Stronger 73. **The solidus line is the line that separates?** - a\) The liquid region from the liquid-solid region - b\) The solid region from the liquid-solid region - c\) The solid region from the gas region - d\) The solid region from the liquid region\ **Answer:** b) The solid region from the liquid-solid region 74. **If the loading is removed after yield strength, what happens to strain?** - a\) Strain becomes zero - b\) Strain remains the same - c\) Strain stops with some recovery - d\) Strain doubles\ **Answer:** c) Strain stops with some recovery