Description : Ammonia leakage in the refrigeration system is detected by (A) Sulphur stick, which on detection gives white smoke (B) Using chemical reagents (C) Its smell (D) Soap solution
Last Answer : Option A
Description : Moisture in freon refrigeration system causes (a) ineffective refrigeration (b) high power consumption (c) freezing automatic regulating valve (d) corrosion of whole system
Last Answer : Ans: c
Description : Mass flow ratio of NH3 in comparison to Freon-12 for same refrigeration load and same temperature limits is of the orderof (a) 1 : 1 (b) 1 : 9 (c) 9 : 1 (d) 1 : 3
Last Answer : Ans: b
Description : Refrigeration in aeroplanes usually employs the following refrigerant (a) Co2 (b) Freon-11 (c) Freon-22 (d) Air
Last Answer : Ans: d
Description : Leakage in a cooking gas cylinder is detected by (A) Radio-isotopes (B) Pouring soap solution on the surface and locating the gas bubbles (C) Halide torch (D) Pungent smell of mercaptans present in the gas
Last Answer : Option D
Description : Which of the following is a widely used refrigerant in vapour compression refrigeration system (using large centrifugal compressor)? (A) Freon (B) Liquid sulphur dioxide (C) Methyl chloride (D) Ammonia
Last Answer : (A) Freon
Description : A certain refrigerating system has a normal operating suction pressure of 10 kg/cm gauge and condensing pressure ofabout 67 kg/cm. The refrigerant used is (a) Ammonia (b) Carbon dioxide (c) Freon (d) Brine
Description : Which of the following is used for refrigeration? (1) Sulphur dioxide (2) Chlorine (3) Freon (4) Phosphine
Last Answer : (3) Freon Explanation: Common refrigerants used in domestic refrigerators are Freon, neon and nitrogen. It flows through four components of refrigerator again and again.
Last Answer : Freon
Description : Highest pressure encountered in a refrigeration system should be (a) critical pressure of refrigerant (b) much below critical pressure (c) much above critical pressure (d) near critical pressure
Description : Absorption system normally uses the following refrigerant (a) Freon-11 (b) Freon-22 (c) C02 (d) ammonia.
Last Answer : Ans: e
Description : Reducing suction pressure in refrigeration cycle (a) lowers evaporation temperature (b) increases power required per ton of refrigeration (c) lowers compressor capacity because vapour is lighter (d) all of the above.
Description : For proper refrigeration in a cabinet, if the temperature and vapour pressure difference between cabinet and atmosphereis high, then (a) bigger cabinet should be used (b) smaller cabinet should ... tight vapour seal should be used (d) refrigerant with lower evaporation temperature should be used
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 : The freon group of refrigerants are (a) halo-carbon refrigerants (b) azeotrope refrigerants (c) inorganic refrigerants (d) hydro-carbon refrigerants
Last Answer : Ans: a
Description : Which of the following refrigerants has lowest freezing point (a) Freon-12 (b) NH3 (c) CO2 (d) Freon-22
Description : Freon group of refrigerants are (a) inflammable (d) toxic (c) non-toxic and non-inflammable (d) non-toxic and inflammable
Description : If diesel is used in a petrol engine a. engine will not run b. engine detonates c. engine gives smoke d. engine knocks
Last Answer : ANSWER a. engine will not run
Description : The general rule for rating refrigeration systems (excepting for CO2 system) is to approximate following h.p. per ton of Refrigeration (a) 0.1 to 0.5 h.p. per ton of refrigeration (b) 0.5 to 0.8 h.p. per ... (c) 1 to 2 h.p. per ton of refrigeration (d) 2 to 5 h.p. per ton of refrigeration
Description : Most of the domestic refrigerators work on the following refrigeration system (a) vapour compression (b) vapour absorption (c) carnot cycle (d) electrolux refrigerator
Description : Aqua ammonia is used as refrigerant in the following type of refrigeration system (a) compression (b) direct (c) indirect (d) absorption
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 : In a refrigeration system, heat absorbed in comparison to heat rejected is (a) more (b) less (c) less for small capacity and more for high capacity. (d) more for small capacity and less for high capacity
Description : An important characteristic of absorption system of refrigeration is (a) noisy operation (b) quiet operation (c) very little power consumption (d) its input only in the form of heating.
Last Answer : Ans: D
Description : Which of the following factors influence whether a reaction will proceed by an SN1, SN2, E1, or E2 mechanism? (a) Structure of the alkyl halide (b) Solvent (c) Concentration of reagents (d) Nature of the nucleophile (e) All of these
Last Answer : All of these
Description : In a refrigeration cycle, the super heating……..C.O.P (a)decreases (b)does not change (c) increases (d)none of the above
Description : Air refrigeration cycle is used in (a) domestic refrigerators (b) gas liquefaction (c)commercial refrigerators (d) Chillers
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
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 : Under-cooling in a refrigeration cycle (a) increases COP (b) decreases COF (c) COP remains unaltered (d) other factors decide COP
Description : Superheating in a refrigeration cycle (a) increases COP (b) decreases COP (c) COP remains unaltered (d) other factors decide COP
Description : One ton of the refrigeration is (a) the standard unit used in refrigeration problems (b) the cooling effect produced by melting 1 ton of ice (c) the refrigeration effect to freeze 1 ton of water at ... ice at 0°C in 24 hours (d) the refrigeration effect to produce 1 ton of ice at NTP conditions
Description : In a refrigeration cycle, the flow of refrigerant is controlled by (a) compressor (b) condenser (c) evaporator (d) expansion valve
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 : Highest temperature encountered in refrigeration cycle should be (a) near critical temperature of refrigerant (b) above critical temperature (c) atcritica. temperature (d) much below critical temperature
Description : Air refrigeration cycle is used in (a) domestic refrigerators (b) commercial refrigerators (c) air conditioning (d) gas liquefaction
Description : Air refrigeration operates on (a) Carnot cycle (b) Reversed Carnot cycle (c) Rankine cycle (d) Brayton cycle.
Description : In S.J. unit, one ton of refrigeration is equal to (a) 210 kJ/min (b) 21 kJ/min (c) 3.5 kJ/min (d) 2.4 kJ/min
Description : One ton of refrigeration is equal to the refrigeration effect corresponding to melting of 1000 kg of ice (a) in 1 hour (b) in 1 minute (c) in 24 hours (d) in 12 hours
Description : Ammonia-absorption refrigeration cycle requires (a) very little work input (b) maximum work input (c) nearly same work input as for vapour compression cycle (d) zero work input
Description : Vapour compression refrigeration is some what like (a) Carnot cycle (b) Rankine cycle (c) reversedCamot cycle (d) reversed Rankine cycle
Last Answer : Ans: C
Description : Velocity of flame propagation in SI engine is maximum for a fuel air mixture which is (a) 10% richer than stoichiometric (b) Equal to stoichiometric (c) More than 10% richer than stoichiometric (d) 10% leaner than stoichiometric
Last Answer : Ans :a
Description : The following statement(s) is/are true concerning newer detection methods of systemic infection. a. Enzyme-linked immunosorbent assay (ELISA) is a rapid immunologic assay used for ... detected using advanced molecular techniques include cytomegalovirus (CMV) and human immunodeficiency virus (HIV)
Last Answer : Answer: a, b, c, d Although the classic detection of infection based on clinical signs of infection and bacterial culture remain the most common clinical tools, increasing ... including CMV and HIV. Furthermore, preliminary investigations into possible detection of fungal pathogens are underway
Description : What place does the Olympic Torch Flame is always lit?
Last Answer : It is an eternal flame in Olympia Greece where the Olympicsbegan.
Description : Metal (M) shows crimson red colour in flame test and its halide is deliquescent then metal (M) could be :
Last Answer : Metal (M) shows crimson red colour in flame test and its halide is deliquescent then metal (M) could be : A. Li B. Mg C. Ca D. Ba
Description : If petrol is used in a diesel engine a. higher knocking will occur b. efficiency will be low c. low power will be obtained d. black smoke will be produced
Last Answer : ANSWER a. higher knocking will occur
Description : The knock in diesel engine occurs due to A. instantaneous and rapid burning of the first part of the charge B. instantaneous auto ignition of the last part of the charge C. delayed burning of the last part of the charge D. reduction of delay period
Last Answer : ANSWER : A