0% 1 Mechanical Engineering Quiz 21 1 / 50 In perpetual inventory control, the material is checked as it reaches its__________________? middle value maximum value minimum value average value 2 / 50 Poisson?s ratio is defined as the ratio of_________________? longitudinal stress and longitudinal strain lateral stress and longitudinal stress longitudinal stress and lateral stress lateral stress and lateral strain 3 / 50 Which is false statement about tempering. Tempering is done to_______________? improve machinability improve toughness improve ductility release stresses 4 / 50 The energy of molecular motion appears as________________? surface tension heat potential energy friction 5 / 50 Cold working________________? alone has no influence on fatigue strength increases the fatigue strength has no influence on fatigue strength decreases the fatigue strength 6 / 50 Large forgings, crank shafts, axles normally contain carbon up to________________? 0.55 to 1.0% 0.20 to 0.45% 0.05 to 0.20% 0.45 to 0.55% 7 / 50 According to Recardo?s theory, detonation occurs due to______________________? instantaneous auto-ignition of last part of charge to be burnt self ignition temperature has nothing to do with detonation improper combustion improper mixing of air and fuel 8 / 50 In a centrifugal pump casing, the flow of water leaving the impeller, is___________________? forced vortex radial flow rectilinear flow free vortex motion 9 / 50 The most effective inhibitor of grain growth, when added in small quantities is__________________? carbon vanadium cobalt manganese 10 / 50 Annealing of white cast iron results in production of_________________? malleable iron spheroidal iron grey iron nodular iron 11 / 50 For burning 1 kg of carbon to CO as per chemically correct combusiton, amount of air required is___________________? 4/3kg 1 kg 8/3kg 2 kg 12 / 50 Hard coke is produced by carborisation of coal at_______________? atmospheric temperature 500-600?C 70O-850?C 95O-1100?C 13 / 50 For the same compression ratio_____________________? Diesel cycle is more efficient?than Otto compression ratio has nothing to do with efficiency Otto cycle is more efficient than the Diesel both Otto and Diesel cycles are, equally efficient 14 / 50 Coaxing is the procedure of increasing__________________? fatigue limit by overstressing the metal by successively increasing loadings metal resistance to corrosion by coating metal strength by cycling metal hardness by surface treatment 15 / 50 A rocket engine for the combustion of its fuel_____________________? uses surrounding air uses compressed atmospheric air carries its own oxygen does not require oxygen 16 / 50 Thermal efficiency of well maintained boiler will be of the order___________________? 20% 50% 40% 90% 17 / 50 Gas turbine works on_______________? Rankine cycle Erricsson cycle Carnot cycle Brayton or Atkinson cycle 18 / 50 A nuclear fission produces energy of following order in MeV___________________? 20,000 200 2000 20 19 / 50 In elliptical trammels_________________? three pairs turning and one pair sliding all four pairs are turning two pairs turning and two pairs sliding one pair turning and three pairs sliding 20 / 50 Two plates spaced 150 mm apart are maintained at 1000?C and 70? The heat transfer will take place mainly by ___________________? free convection radiation convection forced convection 21 / 50 For combustion of a fuel, following is essential_____________________? 02 to support combustion all the three above proper ignition temperature correct fuel air ratio 22 / 50 If the radius of gyration of a compound pendulum about an axis through e.g. is more, then its frequency of oscillation will be_______________? same more less data are insufficient to determine same 23 / 50 The center of pressure of a surface subjected to fluid pressure is the point_______________? similar to metacentre at which all hydraulic forces meet on the surface at which gravitational force acis on the surface at which resultant pres-sure acts 24 / 50 The shear plane in case of bolts should_________________? never be across the threaded portion be normal to threaded portion of shank be parallel to axis of bolt be across threaded portion of shank 25 / 50 Dimensions of surface tension are___________________? MlL2T2 MlL?T2 MlL r2 MlL?Tx 26 / 50 The thermal efficiency of a diesel engine is of the order of_________________? 92% 34% 68% 52% 27 / 50 Longitudinal stress in a thin cylinder is__________________? equal to the hoop stress one-fourth of hoop stress twice the hoop stress half of the hoop stress 28 / 50 A panto graph is a mechanism with___________________? lower pairs higher pairs turning pairs rolling pairs 29 / 50 Hot wire anemometer is used to measure_______________? discharge velocity of gas pressure intensity of liquid pressure intensity of gas 30 / 50 Least force required to draw a body up the inclined plane is W sin (plane inclination + friction angle) applied in the direction___________________? at an angle equal to the angle of friction to the inclined plane along the plane vertically horizontally 31 / 50 In order to prevent knock in the S.I. engines, the charge away from the spark plug should have___________________? low temperature all of the above long ignition delay low density 32 / 50 Mild steel belongs to the following category___________________? alloy steel medium carbon steel low carbon steel high carbon steel 33 / 50 A closed gas turbine in which fuel is burnt directly in the air is not possible because of__________________? increasing gas temperature high pressure ratio paucity of 02 high specific volume 34 / 50 Pick up the correct step used for scheduling a project by C.P.M.__________________? sequence of various activities is made according to their importance required time for each activity is established all of the above a project is divided into various activities 35 / 50 The effort required to lift a load W on a screw jack with helix angle a and angle of friction Wsin(a + ) Wcos(a + ) Wtan(a + ) Wtan(a-) 36 / 50 Formation of frost on evaporator in refrigerator ________________? can be avoided by proper design is immaterial increases heat transfer rate results in loss of heat due to poor heat transfer 37 / 50 Tertiary air is the air used to____________________? transport and dry the coal cool the scanners provide air around burners for obtaining optimum combustion convert CO (formed in lower zone of furnace) into C02 at higher zone 38 / 50 In the aircraft propellers __________________? propulsive matter is ejected from within the propelled body its functioning does not depend on presence of air all of the above the propulsive matter is caused to flow around the propelled body 39 / 50 The approximate straight line mechanism is a____________________? 3 bar linkage four bar linkage 8 bar linkage 6 bar linkage 40 / 50 Practical fluids___________________? possess all the above properties possess surface tension are compressible are viscous 41 / 50 Pessimistic time is___________________? the average time required for a job the minimum time in which an activity can possibly be accomplished the maximum time which an activity might require the most probable time considering all conditions 42 / 50 With increase in speed of vehicle, the back pressure will________________? decrease depend on other factors increase remain unalfected 43 / 50 For which of the following substances, the gas laws can be used with minimum error_________________? superheated steam wet steam dry steam saturated steam 44 / 50 A rocket works with maximum overall efficiency when air craft velocity is equal to the_________________? half the jet velocity twice the jet velocity jet velocity average of the jet velocity 45 / 50 In natural circulation type boiler _______________? water is converted into steam in one . pass without any recirculation water is supplied in durm and through down-comers located in atmospheric conditon it passes to the water wall and rises to drum in the form of mixture of water and steam heating takes place at bottom and the water supplied at bottom gets converted into the mixture of steam bubbles and hot water which rise to drum feed pump is employed to supplement natural circulation in water wall type furnace 46 / 50 The basic constituents of Hastelloy are_________________? nickel, copper, etc nickel, molybdenum etc aluminium, copper etc all of the above 47 / 50 Film boling occurs at _______________________? very high pressures medium pressures very low pressure atmospheric pressures 48 / 50 In the Emerson efficiency plan, a worker receives only his daily wage and no bonus is paid till his efficiency reaches__________________? 661% 75% 50% 80% 49 / 50 Aluminium bronze contains__________________? 10% aluminium and 90% copper 94% aluminium, 4% copper and 0.5% Mn, Mg, Si and Fe 90% magnesium and 9% aluminium with some copper 92.5% aluminium, 4% copper, 2% nickel, and 1.5% Mg 50 / 50 For very high discharge at low pressure such as for flood control and irrigation applications, following type of pump is preferred_________________? axial flow mixed flow reciprocating centrifugal Provide Your Information Your score is The average score is 56% LinkedIn Facebook Twitter 0% Restart quiz Send feedback Share on facebook Facebook Share on twitter Twitter Share on whatsapp WhatsApp PrevMechanical Engineering Quiz 20 Mechanical Engineering Quiz 22Next
