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1) In a counter flow heat exchanger, hot fluid enters at 170°C & leaves at 150°C, while the cold fluid enters at 50°C & leaves at 70°C. The arithmetic mean temperature difference in this case is ______________ °C? a. 20 b. 60 c. 120 d. ∞
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2) Dislocation cross-slip is difficult in those materials, which have___________________? a. Large number of slip systems b. High work hardening rate c. Coarse grain size d. Low stacking fault energy
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3) Cold chisel & hammers are made of_________________? a. High speed steel b. High carbon steel c. Forged steel d. Mild steel
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4) Which of the following relationships is correct for relating the three elastic constants of an isotropic elastic material (where, E = Young’s modulus, G = Modulus of rigidity or shear modulus v = Poisson’s ratio) ? a. E = 2G (1 + v) b. E = G (1 + v) c. E = G (1 + v)/2 d. E = 2G (1 + 2v)
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5) The cathode in an electrochemical cell always carries____________________? a. Negative charge b. Positive charge c. Zero charge d. Positive or negative charge depending upon the nature of the cell
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6) Multistage compression of air as compared to single stage compression offers the advantage of______________? a. Power saving per unit weight of air delivered b. Moisture elimination in the inter-stage cooler c. Increased volumetric efficiency d. All A , B. & C.
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7) _________________ can replace tungsten in high speed steel ? a. Chromium b. Vanadium c. Cobalt d. Molybdenum
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8) In electrical resistance welding, distortion results from the use of improper________________? a. Clamping methods b. Electrodes c. Current d. Filler material
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9) Addition of ____________________ to steel does not help in improving its machinability? a. Sulphur b. Silicon c. Lead d. Phosphorous
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10) Dew point temperature always gives an indication of the __________________ of the moist air ? a. Dryness b. Moisture content c. Coolness d. Latent heat
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11) The most important consideration, while designing the refrigeration system of an aircraft is that the refrigeration system_________________? a. Is as light as possible b. Has very high C.O.P. c. Employs minimum quantity of refrigerant d. Consumer minimum horse power
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12) Consumable electrodes are used in the ____________________ welding? a. Gas b. Arc c. Thermit d. Resistance
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13) An oxidation process is accompanied with decrease in the____________________? a. Number of electrons b. Oxidation number c. Number of ions d. All A , B. & C.
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14) With decrease in the grain size of a material, its creep resistance___________________? a. Increases b. Decreases c. Remain constant d. Either A. or B.; depends on the material
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15) Austempering of steel requires it to be heated to 875°C followed by sudden cooling to 250- 525°C, thereby changing austenite to___________________? a. Sorbite b. Bainite c. Martensite d. Troostite
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16) What is the percentage of chromium in 18-4-1 high speed steel ? a. 1 b. 4 c. 18 d. 23
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17) Electrometallurgical methods of metal extraction is normally used for those metals___________________? a. Whose oxide/ore is not reduced by carbon b. Which fall in the category of alkali & alkaline earth metals c. Which stands higher in the electrochemical series of the metal d. All A, B. & C.
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18) Work required for compression of a gas contained in a cylinder is 7000 kJ. During compression, heat interaction of 3000 kJ causes the surroundings to be heated. Internal energy change of the gas during the compression is __________________ kJ ? a. +4000 b. -4000 c. 10000 d. -10000
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19) Hydrogen can be ________________? a. Used in I.C. engines as fuel b. Liquefied & stored under cryogenic conditions c. Produced by electrolysis of water d. All (A), B. & C.
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20) Air standard Otto cycle is more efficient than the diesel cycle for the same__________________? a. Heat addition & compression ratio b. Heat addition & pressure c. Compression ratio & pressure d. Cylinder dimension & rpm
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21) Percentage of argon (by volume) in dry atmospheric air is about________________? a. 0.09 b. 0.3 c. 0.57 d. 0.94
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22) _____________ is the process of coating the surface of steel with aluminium oxide, thereby imparting it increased resistance to corrosion & oxidation upto a temperature of 700°C ? a. Veneering b. Galvanising c. Electroplating d. Calorising
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23) Normalising of a casting does not__________________? a. Induce stresses in it b. Refine its grain structure c. Reduce segregation d. Improve its mechanical properties
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24) Limestone addition in the blast furnace is done to flux _______________ present in the raw materials? a. SiO2 b. Al2O3 c. MnO2 d. P
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25) In case of brasses, with decreasing zinc percentage and increasing copper percentage, its _____________ increases ? a. Percentage elongation b. Brinell hardness c. Tensile strength d. All A, B & C
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26) Metallic surveying tapes are made of _____________ which has a low co-efficient of expansion & enough strength ? a. Invar b. Hastelloy c. Duralumin d. Monel metal
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27) Titanium is produced by ___________________ of Ti Cl4 ? a. Electrolytic reduction b. Calcium reduction c. Magnesium reduction d. Thermal dissociation
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28) Atomic _______________ is a whole number for an element? a. Number b. Weight c. Radius d. None of these
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29) Out of the following, the lowest packing of atoms exists in ____________________ crystal lattice structure? a. Hexagonal close, packed (hcp) b. Face centred cubic (fcc) c. Body centred cubic (bcc) d. Simple cubic
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30) An abrupt and sudden fall in the reading of barometer is an indication of the____________________? a. Storm b. Rain c. Clear weather d. Cold wave
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31) For the Stoke’s law to be valid in the case of a falling sphere in a fluid, the_____________________? a. Reynolds number (based on sphere diameter) should be < 1 b. Flow around the sphere should be in turbulent region c. Sphere must be metallic d. Fluid density should be constant
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32) Saturated steam at a pressure of 25 kg/cm2 is throttled to attain 5 kg/cm2. Then the outcoming steam will be_________________? a. Wet b. Saturated c. Superheated d. None of these
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33) Which of the following is resistant to the action of both heat & chemicals ? a. Borosilicate glass b. Silica glass c. Soda lime glass d. None of these
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34) The kinematic viscosity (in stoke) and the absolute/dynamic viscosity (in poise) are the same for ______________ at room temperature ? a. Air b. Water c. Mercury d. Alcohol
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35) ______________ wire is never used for making the heating element ? a. Nichrome b. Kanthal c. Invar d. None of these
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36) The heat released by cooling one mole of copper from 400 K to room temperature (300 K) is (assume : Cp of copper is 23 J K-1mole-1) ? a. 2300 J b. 4600 J c. 230 J d. 2.3 × 106 J
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37) The most suitable material for die casting is __________________? a. Iron b. Copper c. Steel d. Nickel
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38) In a totally irreversible isothermal expansion process for an ideal gas, ΔE = 0, ΔH = 0. Then ΔQ and ΔS will be_______________? a. ΔQ = 0, ΔS=0 b. ΔQ = 0, ΔS = +ve c. ΔQ = 0, ΔS = -ve d. ΔQ = +ve, ΔS= +ve
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39) Which of the following materials does not form adherent oxide film on surface ? a. Copper b. Nickel c. Aluminium d. Gold & silver
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40) The emf of a Deniell cell “Zn | Zn2+ || Cu2+ | Cu” can be increased by_________________? a. Decreasing the surface area of the electrodes b. Increasing the concentration of zinc sulphate solution c. Increasing the surface area of the electrodes d. Increasing the concentration of copper sulphate solution
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