Description : The process of breaking up or liquid into fine droplets by spraying is A. vaporization B. atomization C. condensation D. evaporation
Last Answer : ANSWER : B
Description : The air fuel ratio in petrol engines is controlled by a. valve opening / closing b. governing c. carburetion d. scavenging
Last Answer : ANSWER c. carburetion
Description : Vapour lock is a. complete or partial stoppage of fuel supply due to vaporization of the fuel b. locking of carburetor due to high vapor pressure c. excess fuel supply to the engine d. supply of liquid fuel to the engine
Last Answer : ANSWER a. complete or partial stoppage of fuel supply due to vaporization of the fuel
Description : Atomization of spray fluid can achieved by : A. discharging the liquid through an orifice under pressure B. by breaking up the jet of liquid by a blast of _____ C. both A & B D. none
Last Answer : C. both A & B
Description : Solid injection in CI engine means injection of A. solid fuel only B. liquid fuel only C. liquid fuel and air D. solid fuel and air
Description : What is the temperature at which the water vapour in the mixture of water vapour in air, starts condensing called? A. condensation temperature B. dew point temperature C. vaporization temperature D. all of the above
Description : At lower temperatures and pressures, the latent heat of vaporization of a refrigerant (a) decreases (b) increases (c) remains same (d) depends on other factors
Last Answer : Ans: b
Description : Alcohols alone cannot be used in CI engines as a) their self ignition temperature is high b) latent heat of vaporization is high c) all of the mentioned d) none of the mentioned
Last Answer : Answer: c Explanation: None.
Description : Air can be cooled and dehumidified by A. circulating chilled water in tube across air flow B. placing evaporator coil across air flow C. spraying chilled water to air D. all of the mentioned
Last Answer : ANSWER : D
Description : If one or more nozzles are not spraying correctly then ________________ occurs. a) dripping b) misfiring c) cold firing d) none of the mentioned
Last Answer : Answer: b Explanation: If one or more nozzles are not spraying correctly then misfiring occurs and not cold firing.
Description : In a 4 S diesel engine, the term ‘squish’ refers to the (a) Injection of fuel in the precombustion chamber (b) Discharge of gases from the precombustion chamber (c) Entry of air into the combustion chamber (d) Stripping of fuel from the core
Last Answer : Ans :c
Description : Rate of burning in the compression ignition engine can be controlled by a. rate of injection of fuel b. rate of air taken into carburetor c. both a. and b. d. none of the above
Last Answer : ANSWER a. rate of injection of fuel
Description : Solid injection is also called ________________ a) air injection b) mechanical injection c) compression fuel injection d) none of the mentioned
Last Answer : Answer: b Explanation: Generally, solid injection is also called mechanical injection.
Description : In _____________ injection system only one pump is sufficient for multi-cylinder engine. a) air b) mechanical c) compression fuel d) common rail
Last Answer : Answer: d Explanation: None.
Description : Removal of air from the pipeline is termed as ____________ in injection system. a) bleeding b) wound c) sweating d) none of the mentioned
Last Answer : Answer: a Explanation: Generally, the removal of air from the pipeline is termed as bleeding in injection system.
Description : The methods used on fuel injection are : a) air injection b) mechanical injection c) solid fuel injection d) all of the mentioned
Last Answer : Answer: d Explanation: The methods used on fuel injection are air injection, mechanical injection and solid fuel injection.
Description : In electronic fuel injection, there is improvement in the _____________ efficiency due to comparatively less resistance in the intake manifolds which will cause less pressure losses. a) mechanical b) volumetric c) overall d) none of the mentioned
Last Answer : Answer: b Explanation: In electronic fuel injection, there is improvement only in the volumetric efficiency due to comparatively less resistance in the intake manifolds which will cause less pressure losses and no other efficiencies are hindered.
Description : The _____________ sensor, senses rotation of engine camshaft for speed and timing of injection. a) throttle position b) manifold pressure c) camshaft position d) knock
Last Answer : Answer: c Explanation: The camshaft position sensor, senses rotation of engine camshaft for speed and timing of injection whereas the throttle position sensor, senses the movement of the throttle ... engine intake manifold so that the mixture strength can be adjusted with changes in engine load.
Description : With EFI of diesel engines a) sharp start and stop is not possible b) very high injection pressure can be obtained c) sudden cylinder cut-off is impossible d) diagnostic properties are poor
Last Answer : Answer: b Explanation: Generally, with EFI of diesel engines very high injection pressure can be obtained.
Description : Continuous injection system usually has a) plunger pump b) rotary pump c) gear pump d) vane pump
Last Answer : Answer: b Explanation: In common use continuous injection system usually has rotary pump.
Description : Common rail injection system uses injection pressures of the order a) 100-200 bar b) 200-400 bar c) 400-600 bar d) 1500 bar
Last Answer : Answer: d Explanation: Generally, common rail injection system uses injection pressures of the order 1500 bar.
Description : D-MPFI system uses a) port injection b) direct injection c) manifold injection d) throttle body injection
Last Answer : Answer: b Explanation: D-MPFI system uses direct injection and L-MPFI system uses port injection while multipoint fuel injection system uses port injection and throttle body injection.
Description : L-MPFI system uses a) port injection b) direct injection c) manifold injection d) throttle body injection
Last Answer : Answer: a Explanation: L-MPFI system uses port injection while multi-point fuel injection system uses port injection and throttle body injection while D-MPFI system uses direct injection.
Description : A 4S diesel engine, when running at 2000 rpm has an injection duration of 1.5 ms.What is the corresponding of the crank angle in degrees? (a) 18° (b) 9° (c)36° (d) 15°
Last Answer : Ans :a
Description : Which of the following factors increases the tendency of knocking in the CI engines? (a) Increasing both the r and coolant temperatures (b) Increasing both the speed and the injection advance (c) Increasing the speed, injection advance and coolant temperature (d) Increasing the compression ratio
Description : The tendency of knocking in CI engine reduces by (a) High self ignition temperature of fuel (b) Decrease in jacket water temperature (c) Injection of fuel just before TDC (d) Decrease in injection pressure
Description : Mixing of air and fuel in the diesel engine occurs in a. injection pump b. carburetor c. engine cylinder d. inlet manifold
Last Answer : ANSWER c. engine cylinder
Description : A (n) ______printer works by spraying tiny droplets of ink onto the paper: a) ink - jet b) laser c) thermal d) None of The Above
Last Answer : a) ink - jet
Description : .In Hydraulic sprayers, the degree of atomization is primarily a function of A. Liquid pressure and the nozzle characteristics B. Air velocity C. Size of the nozzle D. Size and shape of the atomizer
Last Answer : A. Liquid pressure and the nozzle characteristics
Description : The _____________ sensor, checks the temperature of the ambient air entering the engine for fine tuning the mixture strength. a) engine temperature b) exhaust gas c) air flow d) air inlet temperature
Last Answer : Answer: d Explanation: The air inlet temperature sensor, checks the temperature of the ambient air entering the engine for fine tuning the mixture strength whereas the engine temperature sensor senses the ... gas senor senses the amount of oxygen in the engine exhaust and calculates air-fuel ratio.
Description : The condition of refrigerant before entering the expansion or throttle valve, in a vapour compression system (a) dry vapour (b) wet vapour (c)liquid-vapour mixture (d) high pressure saturated liquid
Last Answer : Ans: d
Description : Choose the wrong statement (a) Temperature of medium being cooled must be below that of the evaporator (b) Refrigerant leaves the condenser as liquid (c) All solar thermally operated absorption systems are capable only of intermittent operation (d) frost on evaporator reduces heat transfer
Last Answer : Ans: a
Description : The lower horizontal line of the refrigeration cycle plotted on pressure-enthalpy-diagram represents (a) condensation of the refrigerant vapour (b) evaporation of the refrigerant liquid (c) compression of the refrigerant vapour (d) metering of the refrigerant liquid
Description : In vapour compression refrigeration system, refrigerant occurs as liquid between (a) condenser and expansion valve (b) compressor and evaporator (c) expansion valve and evaporator (d) compressor and condenser
Last Answer : Ans: c
Description : In a flooded evaporator refrigerator, an accumulator at suction of compressor is used to (a) collect liquid refrigerant and prevent it from going to compressor (b) detect liquid in vapour (c) superheat the vapour (d) increase refrigeration effect
Description : Condensing temperature in a refrigerator is the temperature (a) of cooling medium (b) of freezing zone (c) of evaporator (d) at which refrigerant gas becomes liquid
Description : One of the purposes of sub-cooling the liquid refrigerant is to (a) reduce compressor overheating (b) reduce compressor discharge temperature (c) increase cooling effect (d) ensure that only liquid and not the vapour enters the expansion (throttling) valve
Description : In refrigerator, liquid receiver is required between condenser and flow controlling device, if quantity of refrigerant for system is (a) less than 2 kg (b) more than or equal to 3.65 kg (c) more than 10 kg (d) there is no such consideration
Description : In a vapour compression cycle, the refrigerant immediately after expansion valve is (a) liquid (b) sub-cooled liquid (c) saturated liquid (d) wet vapour
Description : Critical pressure of a liquid is the pressure (a) above which liquid will remain liquid (b) above which liquid becomes gas (c) above which liquid becomes vapour (d) above which liquid becomes solid
Description : In vapour compression cycle, the condition of refrigerant is high pressure saturated liquid (a) after passing through the condenser (b) before passing through the condenser (c) after passing through the expansion or throttle valve (d) before entering the expansion valve
Description : In vapour compression cycle, the condition of refrigerant is saturated liquid (a) after passing through the condenser (b) before passing through the condenser (c) after passing through the expansion throttle valve (d) before entering the expansion valve
Description : Clapeyron equation is applicable for registration at (a) saturation point of vapour (b) saturation point of liquid (c) sublimation temperature (d) triple point.
Description : Which of the following is the lightest and most volatile liquid fuel A. diesel B. kerosene C. fuel oil D. gasoline
Description : Which of the following is the lightest and most volatile liquid fuel? a. diesel b. kerosene c. gasoline d. fuel oil
Last Answer : ANSWER c. gasoline
Description : The changing of solid directly to vapor without passing through liquid state is called a. Evaporation b. Vaporization c. Sublimation d. Condensation
Last Answer : Sublimation
Description : The change of a gas to a liquid is called: w) vaporization x) sublimation y) condensation z) freezing
Last Answer : ANSWER: Y -- CONDENSATION
Description : Why do transition metals have high enthalpy of atomization ?
Last Answer : Ans : it is due to strong metallic bonds and additional covalent bonds
Description : In order to make a phase change from liquid to gas you must add energy equal to the what of vaporization?
Last Answer : Need answer
Description : What is defined as the direct conversion of a substance from the solid to the vapor state or vice versa without passing the liquid state? A. Condensation B. Vaporization C. Sublimation D. Cryogenation