Description : When the humidity ratio of air increases the air is said to be A. dehumidified B. humidified C. heated D. cooled
Last Answer : ANSWER : B
Description : When humidity ratio of air ____ air is said to be dehumidified. A. increases B. decreases C. remains constant D. none of the mentioned
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 : 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 : Unsaturated air (with dry bulb and wet bulb temperatures being 45°C and 25°C respectively) is passed through a water spray chamber maintained at 23°C. The air will be cooled and (A) ... temperature decreasing B) Humidified at constant wet bulb temperature (C) Dehumidified (D) None of these
Last Answer : (A) Humidified with wet bulb temperature decreasing
Description : Unsaturated air (with dry bulb temperature and dew point being 35°C and 18°C respectively) is passed through a water spray chamber maintained at 15°C. The air will be cooled (A) And ... (C) At the same relative humidity (D) And dehumidified with decrease in wet bulb temperature
Last Answer : (D) And dehumidified with decrease in wet bulb temperature
Description : Unsaturated air (with dry and wet bulb temperatures being 35 and 25°C respectively) is passed through water spray chamber maintained at 35°C. The air will be (A) Cooled (B) Humidified (C) Both (A) & (B) (D) Dehumidified
Last Answer : (B) Humidified
Description : In a refrigeration cycle, the flow of refrigerant is controlled by (a) compressor (b) condenser (c) evaporator (d) expansion valve
Last Answer : Ans: d
Description : What is the perfect condition for dehumidification of air? A. air is heated above its dew point temperature B. air is cooled up to its dew point temperature C. air is heated below its dew point temperature D. air is cooled below its dew point temperature
Last Answer : ANSWER : D
Description : The power required to drive a turbo compressor for a given pressure ratio decreases when A. Air is heated at entry B. Air is cooled at entry C. Air is cooled at exit D. Air is heated at exit
Description : The process of breaking up or liquid into fine droplets by spraying is A. vaporization B. atomization C. condensation D. evaporation
Description : The process of breaking up a liquid into fine droplets by spraying is called a. vaporization b. carburetion c. injection d. atomization
Last Answer : ANSWER d. atomization
Description : Cooling water is required for following equipment in ammonia absorption plant (a) condenser (b) evaporator (c) condenser and absorber (d) condenser, absorber and separator (rectifier).
Description : The change in evaporator temperature in a refrigeration cycle, as compared to change in condenser temperature, influences the value of C.O.P. (a) more (b) less (c) equally. (d) unpredictable
Description : The C.O.P. of a refrigeration cycle with lowering of condenser temperature, keeping the evaporator temperatureconstant, will (a) increase (b) decrease (c) may increase or decrease depending on the type of refrigerant used (d) remain unaffected
Description : The refrigeration effect in a dry evaporator compared to flooded evaporator in a similar plant is (a) same (b) more (c) less (d) more or less depending on ambient conditions
Last Answer : Ans: c
Description : The C.O.P of a refrigeration cycle with increase in evaporator temperature, keeping condenser temperature constant, will (a) increase (b) decrease (c) remain unaffected (d) may increase or decrease depending on the type of refrigerant used
Description : The advantage of dry compression is that (a) it permits higher speeds to be used (b) it permits complete evaporation in the evaporator (c) it results in high volumetirc and mechanical efficiency (d) all of the above
Description : Where does the lowest temperature occur in a vapour compression cycle ? (a) condenser (b) evaporator (c) compressor (d) expansion valve
Last Answer : Ans: b
Description : If the evaporator temperature of a plant is lowered, keeping the condenser temperature constant, the h.p. of compressorrequired will be (a) same (b) more (c) less (d) more/less depending on rating
Description : If a heat pump cycle operates between the condenser temperature of +27°C and evaporator temperature of - 23°C,then the Carnot COP will be (a) 0.2 (b) 1.2 (c) 5 (d) 6
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
Description : A refrigeration cycle operates between condenser temperature of + 27°C and evaporator temperature of- 23°C. TheCarnot coefficient of performance of cycle will be (a) 0.2 (b) 1.2 (c) 5 (d) 6
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 : Formation of frost on evaporator in refrigerator (a) results in loss of heat due to poor heat transfer (b) increases heat transfer rate (c) decreases compressor power. (d) can be avoided by proper design
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 : The higher temperature in vapour compression cycle occurs at (a) compressor discharge. (b) expansion valve (c) evaporator (d) condenser discharge
Description : The bank of tubes at the back of domestic refrigerator are (a) condenser tubes (b) evaporator tubes (c) refrigerant cooling tubes (d) capillary tubes
Description : For better COP of refrigerator, the pressure range corresponding to temperature in evaporator and condenser must be (a) small (b) high (c) equal (d) anything
Description : The moisture in a refrigerant is removed by (a) evaporator (b) safety relief valve (c) dehumidifier (d) driers
Description : In refrigerators, the temperature difference between the evaporating refrigerant and the medium being cooled should be (a) high, of the order of 25° (b) as low as possible (3 to 11°C) (c) zero (d) any value
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 : Air at dry bulb temperature Td1 is passed through the heating coil and some amount of air is by passed unaffected and leaves with dry bulb temperature Tb2 and the temperature of heated air is Td3 (where Td2 < Td3), what is the ... - Td1) / (Td2 - Td3) D. Bypass Factor = (Td2 - Td3) / (Td2 - Td1)
Description : When, H1 = Total heat of air entering the coil (heating or cooling) H2 = Total heat of air leaving the coil (heating or cooling) H3 = Total heat of air at the end of ... A. cooling and humidification B. cooling and dehumidification C. heating and humidification D. heating and dehumidification
Last Answer : ANSWER : C
Description : Through what is feed water from hot-well is passed through, before entering steam and water drum in Lamont boiler? a. Evaporator tubes b. Economizer c. Distributor header d. Circulating pump
Last Answer : b. Economizer
Description : The benchmarking parameter for air conditioning equipment is a) kW/Ton of Refrigeration b) kW/ kg of refrigerant handled c) kcal/m3 of chilled water d) Differential temperature across chiller
Last Answer : kW/Ton of Refrigeration
Description : The benchmarking parameter for air conditioning equipment is a) kW/Ton of Refrigeration b) kW/ kg of refrigerant handled c) kcal/m3 of chilled water d) Differential temperature across chiLLER
Description : The basic meter movement responds to the flow of current through its coil. Therefore, this meter movement may be used as a/an _____________. A. voltmeter by placing a resistance in parallel with the ... in parallel with the coil D. ammeter by placing a low resistance in parallel with the coil
Last Answer : Answer: D
Description : When air passes through silica gel, A. it absorbs water vapour molecules B. latent heat of condensation is released C.dbt of air increases D. all of the mentioned
Description : Heating and humidification is done in A. summer air conditioning B. winter air conditioning C. both of the mentioned D. none of the mentioned
Description : In sensible heating or cooling, A. work done remains constant B. dry bulb temperature or air remains constant C. both of the mentioned D. none of the mentioned
Last Answer : ANSWER : A
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 : 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 : 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 _____________ sensor, monitors mass or volume of air flowing into the intake manifold for adjusting the quantity of fuel. a) engine temperature b) exhaust gas c) air flow d) air inlet temperature
Last Answer : Answer: c Explanation: The air flow sensor, monitors mass or volume of air flowing into the intake manifold for adjusting the quantity of fuel while exhaust gas senor senses the amount of oxygen in the engine exhaust and calculates air-fuel ratio.
Description : The _____________ sensor senses the temperature of the engine coolant, and from this data the computer adjusts the mixture strength to rich side for cold starting. a) engine temperature b) exhaust gas c) air flow d) air inlet temperature
Last Answer : Answer: a Explanation: The engine temperature sensor senses the temperature of the engine coolant, and from this data the computer adjusts the mixture strength to rich side for cold starting while the ... gas senor senses the amount of oxygen in the engine exhaust and calculates air-fuel ratio.
Description : In _____________ sensor, output voltage changes in proportion to air-fuel ratio. a) engine temperature b) exhaust gas c) air flow d) air inlet temperature
Last Answer : Answer: b Explanation: Only in exhaust gas sensor, output voltage changes in proportion to air-fuel ratio.
Description : _____________ senor senses the amount of oxygen in the engine exhaust and calculates air-fuel ratio. a) Engine temperature b) Exhaust gas c) Air flow d) Air inlet temperature
Last Answer : Answer: b Explanation: Exhaust gas senor senses the amount of oxygen in the engine exhaust and calculates airfuel ratio while engine temperature sensor senses the temperature of the engine coolant, and from this data the computer adjusts the mixture strength to rich side for cold starting.
Description : Surging basically implies A. Unsteady, periodic and reversed flow B. Forward motion of air at a speed above sonic velocity C. The surging action due to the blast of air produced in a compressor D. Forward movement of aircraft