Questions for ACMT 1. the Tendency of a Deformed Solid to Regain Its

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Questions for ACMT 1. the Tendency of a Deformed Solid to Regain Its Questions for ACMT 1. The tendency of a deformed solid to regain its actual proportions instantly upon unloading known as _ a) Perfectly elastic b) Delayed elasticity c) Inelastic effect d) Plasticity 2. How is Young’s modulus of elasticity defined? 3. The permanent mode of deformation of a material known as _____________ a) Elasticity b) Plasticity c) Slip deformation d) Twinning deformation 4. The ability of materials to develop a characteristic behavior under repeated loading known as ______ a) Toughness b) Resilience c) Hardness d) Fatigue 5. What is the unit of tensile strength of a material? a) engineering-materials-metallurgy-questions-answers-mechanical-properties-q5 b) kg/cm2 c) engineering-materials-metallurgy-questions-answers-mechanical-properties-q5-2 d) cm2/kg 6. Which of the following factors affect the mechanical properties of a material under applied loads? a) Content of alloys b) Grain size c) Imperfection and defects d) Shape of material 7. The ability of a material to resist plastic deformation known as _____________ a) Tensile strength b) Yield strength c) Modulus of elasticity d) Impact strength 8. The ability of a material to be formed by hammering or rolling is known as _________ a) Malleability b) Ductility c) Harness d) Brittleness 9. What type of wear occurs due to an interaction of surfaces due to adhesion of the metals? a) Adhesive wear b) Abrasive wear c) Fretting wear d) Erosive wear 10. Deformation that occurs due to stress over a period of time is known as ____________ a) Wear resistance b) Fatigue c) Creep d) Fracture 11. The response of a material due to the function of heat is known as __________ a) Mechanical property b) Electrical property c) Chemical property d) Thermal property 12. The heat capacity of a material defined as ___________ 13. Specific heat of materials is expressed in terms of __________ a) W/m K b) J/K c) J/kg K d) m3/kg 14. What effect does the addition of thermal energy have on a material? a) Thermal contraction b) Thermal expansion c) No change d) Reproduction 15. Which term is used to define the temperature at which a substance changes its status from solid to liquid? a) Boiling point b) Melting point c) Condensation point d) Freezing point 16. The melting point of Iron (Fe) is _________ a) 660oC b) 1084oC c) 419oC d) 1538oC 17. The ability of a body to withstand sudden and severe temperature changes is known as________ a) Thermal shock resistance b) Thermal resistance c) Thermal transmittance d) Deployment 18. How is the spalling resistance index defined? 19. What effect do thermal variations in volume have on a body? a) Expansion b) Contraction c) Cracking d) Phase transformation 20. The temperature at which plastics begin to become softer and defer under a load is known as _____ a) Softening point b) Melting point c) Eutectic point d) Heat distortion point 21. What is the attribute of a material which resists the flow of electricity known? a) Conductivity b) Thermoelectricity c) Dielectric strength d) Resistivity 22. How is conductivity of a material defined? 23. What is the electrical conductivity of Aluminum? a) 6.3 * 107 b) 5.9 * 107 c) 3.5 * 107 d) 1 * 107 24. What is the electrical resistivity of Copper? a) 1.59 * 10-8 b) 1.68 * 10-8 c) 2.65 * 10-8 d) 5.9 * 10-8 25. Measured using an Electrical Conductivity meter, what is the order of resistivity of superconducting materials? a) 10-8 b) 1016 c) ∞ d) 0 26. Which of the following represents the energy band diagram of a semiconducting material? 27. Which of the following processes is not an application of thermoelectric effect? a) Seebeck effect b) Peltier effect c) Thomson effect d) Ettingshausen effect 28. The insulating capacity of material against high voltages is known as _______ a) Dielectric strength b) Thermoelectricity c) Electromechanical effect d) Electrochemical effect 29. What is the nature of the coefficient of resistance of an insulator? a) Positive b) Negative c) Zero d) Infinite 30. What is the dielectric strength of mica? a) 118 MV/m b) 2000 MV/m c) 3 MV/m d) 1012 MV/m 31. The property of a material that produces an opposing magnetizing force, which removes the preceding magnetizing effect, is called as ___________ a) Permeability b) Coercive force c) Hysteresis d) Superconductivity 32. How is magnetic permeability defined? 33. What is the magnetic permeability of Iron? a) 2.5 * 10-1 b) 2 * 105 c) 1.26 * 10-4 d) 100 34. The quantity or effectiveness of the energy emitted known as ____________ a) Refraction b) Reflectivity c) Emissivity d) Luminance 35. What is the emissivity of aluminum foil? a) 0.03 b) 0.9 c) 0.02 d) 0.04 36. The ability of a substance to neutralize the acidic nature of the material is known as ______ a) Corrosion resistance b) Chemical composition c) Alkalinity d) Chemical equilibrium 37. The ability of a metal which helps it to form a smooth cast is known as ______ a) Machinability b) Formability c) Solderability d) Castability 38. What is the machinability index of soft cast iron? a) 100 b) 30 c) 80 d) 70 39. Which of the following is an application of Tin solder 35? a) Tinning and filling of seams b) Plumbing c) Secondary soldering d) For materials which are difficult to solder 40. Which property helps a material to absorb lubricants? a) Density b) Porosity c) Soldering d) Absorptivity 41. What is the unit of diffusion coefficient? a) mol m-2 s-1 b) mol m-3 c) m2 s-1 d) KJ mol-1 42. What is Fick’s first law of diffusion? 43. Which of these represents concentration-distance profile for steady-state flow? 44. What is Fick’s second law of diffusion? 45. What is the diffusion constant (Do) when copper is dissolved in copper? a) 0.2 * 10-4 b) 0.15 * 10-4 c) 1.98 * 10-4 d) 5400 * 10-4 46. Plain carbon steels are alloys mainly consisting of _________ a) Iron and Carbon b) Potassium and Iron c) Carbon and Potassium d) Carbon and Indium 47. Which of the following attributes explain why pure metals are not frequently used in engineering applications? a) Hardness b) Brittleness c) Softness d) Luster 48. Which of the following is also known as mild steel? a) Plain carbon steel b) Low carbon steel c) Medium carbon steel d) High carbon steel 49. What is the composition of carbon in medium carbon steels? a) 0.05% b) 0.1% – 0.3% c) 0.25% – 0.6% d) More than 0.6% 50. Which of these are applications of high-carbon steel? a) Gears, valves b) Steel wires, sheets, screws c) Clutch discs, valve springs d) Machine tools, leaf and coil springs 51. What is the maximum forging temperature of 1.1% carbon steel? a) 1049oC b) 1082oC c) 1140oC d) 1171oC 52. Which steels are generally used for making connecting rods and gear shafts? a) Low carbon steels b) Medium carbon steels c) High carbon steels d) Stainless steels 53. What is the maximum amount of manganese in carbon steels? a) 1.65% b) 1.50% c) 0.60% d) 0.40% 54. What are the advantages of plain carbon steels over alloy steels? a) Inexpensive but hard to handle b) Expensive but easy to handle c) Inexpensive and easy to handle d) There are no advantages of plain carbon steels 55. What kind of steel requires definite amounts of other alloying elements? a) Carbon steel b) Alloying steel c) Stainless steel d) Tool steel 56. Which of these is not a function of alloy steels? a) Increases strength b) Improves ductility c) Reduces cost d) Improves machinability 57. Steels containing up to 3% to 4% of one or more alloying elements are known as ________ a) Low alloy steels b) HSLA steels c) High alloy steels d) Stainless steels 58. What does AISI steel stand for? a) American-Indian Steel Institute b) American-Indian Society of Iron c) American Iron and Steel Institute d) Alloys, Iron and Steel Institute 59. Which of these is not an application of HSLA steels? a) Bridges b) Automobiles and trains c) Building columns d) Leaf and coil springs 60. Steels containing more than 5% of one or more alloying elements are known as ________ a) HSLA steels b) High alloy steels c) Tool and die steels d) Stainless steels 61. Which of the following groups of alloying elements stabilize austenite? a) Ni, Mn, Cu, and Co b) Cr, W, Mo, V, and Si c) Cr, W, Ti, Mo, Nb, V, and Mn d) Co, Al, and Ni 62. Which family of steels are referred to as chromoly? a) 40xx b) 41xx c) 43xx d) 44xx 63. What is the common name of COR-TEN steel? a) Weathering steel b) Control-rolled steel c) Pearlite-reduced steel d) Microalloyed steel 64. Alloy steels containing 0.05% to 0.15% of alloying elements are called _______ a) Weathering steel b) Stainless steel c) Tool and die steel d) Microalloyed steel 65. Which is the primary element used for making stainless steel alloy? a) Chromium b) Zirconium c) Vanadium d) Indium 66. Addition of _______ gives stainless steels an austenitic structure. a) Molybdenum b) Carbon c) Nickel d) Vanadium 67. Stainless steels with little carbon and no nickel are called ________ a) Ferritic stainless steel b) Austenitic stainless steel c) Martensitic stainless steel d) Duplex stainless steel 68. Stainless steels with high strength, but low corrosion resistance are known as _______ a) Austenitic stainless steel b) Ferritic stainless steel c) Martensitic stainless steel d) Duplex stainless steel 69.
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