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1) If curing occurs at temperature more than 100°C porosity results in which area of denture______________? a. Hard thick central area b. Thin Palatal area c. Thin area of flanges d. Porosity is uniformly distributed
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2) All of the following statements about the differences between self-polymerizing acrylic resins and heat-cured resins are true EXCEPT______________? a. The former have a lower molecular weight b. The former have higher residual monomer content c. The former are more porous d. The former have greater transverse strength
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3) Deformation that is recovered upon removal of an externally applied force or pressure is known as_____________? a. Young’s modulus b. Plastic strain c. Elastic strain d. Flexural strain
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4) Coefficienty of thermal expansion of tooth enamel is closest to_______________? a. Slicate cement b. Composite c. GIC d. Polycarboxylate
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5) The forces that hold atoms together are called_____________? a. Primary forces b. Secondary forces c. Cohesive forces d. Ionic forces
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6) A material which partially transmits light & partially scatters it________________? a. Reflector b. Translucent c. Transparent d. Opaque
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7) Angles between Adhesive and Adherent is Zero degree, it indicates_______________? a. Complete wetting of surfaces b. Rough surfaces between Adhesive & Adherent c. Adherent and Adhesive molecules are tangent to each other d. Irregularities present between Adherent surfaces
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8) Brazilian test is used to determine the ultimates tensile strength of_________________? a. Ductile materials b. Flexible materials c. Brittle materials d. Malleable materials
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9) For adhesion to be present between solid and liquid________________? a. Liquid should wet solid surface b. Mechanical interlocking should be present c. Should have high contact angle d. None of the above
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10) When two metals are completely miscible in liquid state and they remain completely mixed on solidifiation, the alloy formed is called________________? a. Solid solution b. Eutectic mixture c. Peritectic mixture d. Inter metallic compounds
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11) A crystal in metal substructure is_______________? a. Grain b. Nucleus c. Stroma d. None of the above
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12) Munsell system is used to_________________? a. Define and measure colour qualitatively b. Define and measure physical properties of gold alloys c. Evaluate brittleness of different alloys d. Measures different colours quantitatively
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13) Space lattice refers to_______________? a. Inter atomic movement b. Inter atomic imbalance c. Arrangement of atoms d. Arrangement of molecules
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14) The strain that occurs when a material is stressed to its proportional limit is______________? a. Resilience b. Maximum flexibility c. Toughness d. Elastic limit
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15) Liquids which become more rigid as the rate of deformation increases is termed as_____________? a. Thixotropic b. Pseudoplastic c. Dilatant d. Newton
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16) A restorative material which has a high proportional limit, compared with one with a lower proportional limit would have________________? a. Greater ductility b. Greater toughness c. A higher modulus of elasticity d. A higher modulus of elasticity e. More resistance to permanent deformation
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17) Which of the following has the highest modulus of elasticity ? a. Dentin b. Enamel c. Amalgam d. Composite Resin
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18) The wetting of an adherent surface by an adhesive is related to________________? a. Surface energy of the adherent b. Surface texture of the adherent c. Surface tension of the adherent d. Nature of the adherent that is crystalline or amorphous
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19) Coefficient of thermal expansion of which of following is most similar to that of tooth ? a. Gold inlay b. Acrylic resin c. Silicate cement d. Gold foil
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20) The stiffness of a dental gold alloy is determined by its________________? a. Proportional limit b. Modulus of elasticity c. Ultimate tensile strength d. Flow
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21) Ductility of a material is a measure of it’s_______________? a. Grain elongation b. Anealing c. Cold working d. Work hardening
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22) Sublimation is the conversion of a___________________? a. Solid directly to gas b. Gas to liquid and then to soild c. Gas directly to liquid d. Solid to liquid and then to gas
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23) Modulus of elasticity means_______________? a. Rigidity or stiffness of the material b. Ability to be stretched with permanent deformation c. Ductility of a material d. Malleability of the metal
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24) When solid gets wet completely contact angle is______________? a. 90° b. 0° c. 0 – 90° d. >90°
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25) Brinnel hardness number of a dental gold alloy is directly proportional to its______________? a. Tensile strength b. Elongation c. Modulus of elasticity d. Modulus of resilience
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26) Hardness number which does not depend on the ductility of metal_____________? a. KNH b. VHN c. RHN d. BHN
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27) The greatest stress which may be produced in a material such that stress is directly proportional to the strain is know as_____________? a. The elastic limit b. The proportional limit c. The yield strength d. Modulus of elasticity
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28) The modulus of elasticity is defined as_______________? a. The stress at the proportional limit b. The strain at the proportional limit c. The stress/strain ratio within the proportional limit d. None of the above
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29) Strain is defined as_____________? a. An applied load or force b. A deformation resulting from an applied load c. An external force opposing an applied load d. An internal force opposing an applied load
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30) A good adhesive should possess all of the following EXCEPT________________? a. High adherend wetting b. High contact angle c. Low contact angle d. High flow
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31) In measuring Vickers hardness no. Which of the following is used________________? a. Spherical indenter b. Steel ball indentation c. Rhomboid shaped indenter d. 136-degree diamond pyramid
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32) The simplest alloy is a_______________? a. Solid solution b. Eutectic alloy c. Peritectic allowy d. Ternary alloy
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33) Materials which has high compressive strength and low tensile strength is classified with property of________________? a. Ductility b. Brittleness c. Malleability d. Resilient
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34) Maxwell – Voigt Model is to determine________________? a. Elastic Behaviour b. Plastic Behaviour c. Viscoelastic Behaviour d. All of the above
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35) KHN value of Amalgam is_________________? a. 90 b. 343 c. 67 d. 450
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36) The melting point of silver is_____________? a. 1063° centigrade b. 960° Centigrade c. 850° Centrigrade d. 1123° Centrigrade
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37) Non metal which conducts elactricity______________? a. Graphite b. Carbon c. Acrylic d. Porcelain
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38) Etching of dentin does not include_____________? a. Removal of smear layer b. Exposure of collagen fibers c. Opening of dentinal tubules d. Increases surface energy
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39) The Knoop Hardness Number of Microfilled composite Restorative material ranges from____________? a. 50 – 60 KHN b. 25 – 35 KHN c. 15 – 20 KHN d. 40 – 48 KHN
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40) The elastic of plastic deformation to fracture a material is its_______________? a. Toughness b. Brittleness c. Young’s modulus d. Proportional limit
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