Standard air is the: a. Mass of 1 cubic meter of dry air at 20°C and atmospheric pressure b. Mass of a cubic meter of air at atmospheric conditions c. Volume of air at ambient temperature and atmospheric pressure d. Volume of 1 kg of dry air at 21°C and atmospheric pressure at sea level or 101.325 kPa e. Volume of 1 kg of air at 15°C and 100 kPa

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Answer: D

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Description : The specific volume of air is expressed as the volume of: a. 1 kg of air at 101.325 kPa in cm3 b. 0.833 kg of air at standard pressure and temperature in m3 c. 1 kg of air at 101.325 ... d. 1 g of air occupied at any temperature and pressure e. 1 kg of air, regardless of temperature and pressure

Last Answer : Answer: C

Description : Calculate the volume of 1 mole of a gas at exactly 20°C at a pressure of 101.35 kPa.

Last Answer : Calculate the volume of 1 mole of a gas at exactly 20°C at a pressure of 101.35 kPa.

Description : A vessel with a volume of cubic meter contains liquid water and water vapor ion equilibrium at 600 kPa. The liquid water has mass of1kg. Using the steam table, calculate the mass of the water vapor.  A. 0.99kg  B. 1.57 kg  C ... / kg vg = 0.3157 m^3 / kg Vtot = mƒ vƒ + mg vg mg = (tot-mƒ vƒ) / vg

Last Answer : 3.16 kg

Description : An air-water vapour mixture has a dry bulb temperature of 60°C and a dew point temperature of 40°C. The total pressure is 101.3 kPa and the vapour pressure of water at 40°C and 60°C are 7.30 kPa and 19.91 kPa respectively ... air is: (A) 0.048 (B) 0.079 (C) 0.122 (D) 0.152

Last Answer : (D) 0.152

Description : Height of atmosphere, if atmospheric density is 1.29 kg m-3 and atmospheric pressure is 101 kPa, is A. 7839.4 m B. 7829.4 m C. 7849.4 m D. 7859.4 m

Last Answer : 7829.4 m

Description : The volume of standard air is _____ m3/kg of dry air. a. 0.533 b. 0.633 c. 0.733 d. 0.833 e. 0.933

Last Answer : Answer: D

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 : Dry-bulb temperature is: a. The absolute temperature corresponding to the atmospheric pressure b. The same as the wet-bulb temperature if the relative humidity is less than 100% c. Not required ... d. The temperature of the air measured with an ordinary thermometer e. The dew point temperature

Last Answer : Answer: D

Description : Normal temperature and pressure (N.T.P.) corresponds to (A) 0°C and 760 mm Hg (B) 15°C and 760 mm Hg (C) 20°C and 760 mm Hg (D) 0°C and 1 kgf/cm2

Last Answer : (C) 20°C and 760 mm Hg

Description : Which one of the following statement is not correct for the volumetric efficiency of a reciprocating air compressor? A. It decreases with increase in ambient temperature B. It increases with ... It increases with decrease in clearance ratio D. It decreases with increases in delivery pressure

Last Answer : ANSWER : A

Description : An engine working on air standard Otto cycle has a cylinder diameter of 10 cm and stroke length of 15 cm. The ratio of specific heats for air is 1.4. If the clearance volume is 196.3 cc and the heat supplied per kg of air per ... kg of air is a. 879.1 kJ/ b. 890.2 kJ c. 895.3 kJ d. 973.5 kJ

Last Answer : ANSWER d. 973.5 kJ

Description : A Rotameter through which air at room temperature and atmospheric pressure is flowing gives a certain reading for a flow rate of 100 cc/sec. If helium (molecular weight 4) is used and Rotameter shows the same reading, the flow rate (cc/sec) is (A) 26 (B) 42 (C) 269 (D) 325

Last Answer : (C) 269

Description : The average temperature of sewage in India, is A. 10°C B. 15°C C. 20°C D. 25°C

Last Answer : ANS: C

Description : 5 days-biochemical oxygen demand (BOD5) is taken at a temperature of A. 0°C B. 15°C C. 20°C D. 25°C

Last Answer : ANS: C

Description : Air initially at 101. 3 kPa and 40°C and with a relative humidity of 50%, is cooled at constant pressure to 30°C. The cooled air has a (A) Higher dew point (B) Higher absolute (specific) humidity (C) Higher relative humidity (D) Higher wet bulb temperature

Last Answer : (C) Higher relative humidity

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 : A diesel engine is usually more efficient than a spark ignition engine because a. Diesel being a heavier hydrocarbon, release more heat per kg than gasoline b. The air standard efficiency of diesel ... an Spark ignition engine d.Self ignition temperature of diesel is higher than that of gasoline.

Last Answer : ANSWER c. The compression ratio of a diesel engine is higher than that of an S.I engine

Description : Dew point can be best defined as the: a. Absolute temperature at which air, upon heating, will evaporate moisture b. . Percentage of moisture that air can hold at a given temperature ... to condense should the temperature drop further e. . Atmospheric pressure at which air will condense moisture

Last Answer : Answer: D

Description : If 850 kg liquid occupies volume of one cubic meter, men 0.85 represents its (A) Specific weight (B) Specific mass (C) Specific gravity (D) Specific density

Last Answer : Answer: Option C

Description : A five day B.O.D. at 15°C of the sewage of a town is 100 kg/day. If the 5 day B.O.D. per head at 15°C for standard sewage is 0.1 kg/day, the population equivalent is A. 100 B. 1000 C. 5000 D. 10000

Last Answer : ANS: D

Description : While swimming at depth of120m in a fresh water lake, A fish emits an air bubbles of volume 2.0mm³ atmospheric pressure is 100kPa. What is the pressure of the bubble?  a) 217.7 kPa  b) 317.7 kPa  c) 417.7 kPa  d) 517.7 kPa Formula: P= δh

Last Answer : 217.7 kPa

Description : While swimming a depth of 13m in a fresh water lake a fish emits an air bubble of volume 2 mm² atmospheric pressure is 100kpa what is the original pressure of the bubble.  a. 217.17 kpa  b. 119 kpa  c. 326.15 kpa  d. 210 kap Pabs = Pg + Patm

Last Answer : 217.17 kpa

Description : The air standard Otto cycle comprises a two constant pressure processes and two constant volume processes b two constant pressure and two constant entropy processes c. two constant volume processes and two constant entropy processes d. none of the above.

Last Answer : ANSWER (c) two constant volume processes and two constant entropy processes

Description : Relative humidity is a) the ratio of water vapour in the air compared to the total amount water vapour the air could contain at a given temperature b) equal to the dry bulb temperature divided by the wet bulb ... of dry air e) the ratio of the mass of water vapour divided by the mass of wet air

Last Answer : ANSWER : A

Description : With suction pressure being atmospheric, increase in delivery pressure with fixed clearance volume A. increase volumetric efficiency B. decrease volumetric efficiency C. does not change volumetric efficiency D. First increase volumetric efficiency and then decrease it

Last Answer : ANSWER : B

Description : A liquid mixture contains 30% o-xylene, 60% p-xylene and 10%. m￾xylene (all percentages in w/w). Which of the following statements would be true in respect of this mixture? (A) The mixture exhibits ... : o-xylene 30, p-xylene 60 and m-xyoene 10 (D) The mixture contain optical isomers

Last Answer : (A) The mixture exhibits an azeotrope at 101.3 kPa

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 dew point is the: a. Dry bulb temperature on a psychrometer b. Temperature at which water vapour will start to be absorbed into the air c. Temperature below which water vapour will start to ... vapour will start to condense out of the air e. Temperature at which water will start to evaporate

Last Answer : Answer: C

Description : Citrus seeds can be stored with Charcoal at following temperature in dry conditions. a. 0-3°C b. 3-10°C c. 10-15°C d. Above 15°C

Last Answer : 3-10°C

Description : In a constant pressure process steam is generated from 10 bar and 0.8 dry condition till it become dry and saturated. Determine amount of heat added per kg of steam. From steam table at 10 bar Tsat = 179.9°C hf = 762.6 kl/kg, hg = 2776.2 kJ/kg 

Last Answer : Constant pressure process Final condition of steam is dry saturated Enthalpy of dry steam = hg= hf + hfg =2776.2 KJ/Kg .Given Latent heat of vaporization = hfg = hg - hf =2776.2-762.6 =2013.6 KJ/Kg Initial condition ... hfg = 762.6+0.8 X 2013.6 =2373.48 KJ/Kg Heat added = hg-hw = 402.72 KJ/kg

Description : People living at sea level have around 5 million RBC per cubic millimeter of their blood whereas those living at an altitude to 5400 metres have around 8 million. This is because at high altitude ... required amount of O2 to survive (d) there is more UV radiation which enhances RBC production.

Last Answer : (c) atmospheric O2 level is less and hence more RBCs are needed to absorb the required amount of O2 to survive

Description : In a reciprocating air compressor the compressor work per kg of air A. Increases as clearance volume increases B. Decreases as clearance volume increases C. Is independent of clearance volume D. Increases with clearance volume only of multistage compressor

Last Answer : ANSWER : C

Description : A standard ice point temperature corresponds to the temperature of (a) water at 0°C (b) ice at - 4°C (c) mixture of ice, water and vapour under equilibrium conditions under NTP conditions (d) mixture of ice and water Under equilibrium conditions.

Last Answer : Ans: D

Description : For an engine operating on air standard Otto cycle, the clearance volume is 10% of the swept volume. The specific heat ratio of air is 1.4. The air standard cycle efficiency is a. 38.3 % b. 39.8 % c. 60.2 % d. 61.7 %

Last Answer : ANSWER d. 61.7%

Description : A supercharger is used in the engines of earthmoving machines at higher altitudes because (a) The ambient atmospheric pressure is less at higher altitudes (b) Four-cycle engines depend on the suction ... rugged enough for higher altitude (d) The ambient temperature is less as the altitude is higher

Last Answer : (a) The ambient atmospheric pressure is less at higher altitudes

Description : A gas at 0 degrees C and at normal atmospheric pressure has a volume of 273 cubic centimeters. If it is held at constant pressure until its volume is doubled, its temperature will be which one of the ... it be w) 2 degrees Celsius x) 200 degrees Celsius y) 273 degrees Celsius z) 546 degrees Celsius

Last Answer : ANSWER: Y -- 273 DEGREES CELSIUS

Description : A rectangle-shaped open-to-sky tank of water has a length of 2 m and a width of 1 m. If the atmospheric pressure is assumed to be 100 kPa and thickness of the tank walls is assumed to be negligible, the force exerted by ... of water is A. 20 kN B. 50 kN C. 100 kN D. 200 kN

Last Answer : 200 kN

Description : In troposphere (the weather domain), the temperature 't' at height 'h' above the spa level in metres is given by (where, temperature at sea level is 15°C and t is in °C.) (A) t = 15 - 0.0065h (B) t = 15 + 0.0065h (C) t = 0.0035h -15 (D) t = 15 - 0.0035h

Last Answer : (A) t = 15 - 0.0065h

Description : In troposphere (the weather domain), the temperature 't' at height 'h' above the sea level in metres is given by (where, temperature at sea level is 15°C and t is in °C.) (A) t = 15 - 0.0065 h (B) t = 15 + 0.0065 h (C) t = 0.0035 h - 15 (D) t = 15 - 0.0035 h

Last Answer : (A) t = 15 - 0.0065 h

Description : What is the specific humidity? A. the ratio of the mass of water vapour to the mass of the total mixture of air and water vapour B. the ratio of the mass of dry air to the mass of the total mixture ... ratio of the mass of water vapour to the mass of dry air in a mixture of air and water vapour

Last Answer : ANSWER : D

Description : A 0.064 kg of octane vapor (MW = 114) is mixed with0.91 kg of air (MW = 29.0) in the manifold of an Engine. The total pressure in the manifold is 86.1 kPa, and a temperature is 290 K. assume octane behaves ideally. What is ... of the air in the mixture in KPa?  a. 46.8  b. 48.6  c. 84.6  d. 64.8

Last Answer : 84.6

Description : Which one of the following statements is correct ? a) For water at 100o Celsius at sea level, the vapour pressure is equal to atmospheric pressure b) Surface energy (or tension) is caused by ... it both in static and in dynamic conditions d) Air is 50,000 times more compressible than water

Last Answer : c) Viscosity of a fluid is the property exhibited by it both in static and in dynamic conditions

Description : Wet-bulb temperature is: a. The temperature indicated by a thermometer whose bulb covered by a water-wetted wick and exposed to a rapidly moving stream of air b. The same as the dry-bulb ... point temperature d. Always less than the dry-bulb temperature e. Not required to find the relative humidity

Last Answer : Answer: A

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 : For water at 300°C, it has a vapour pressure 8592.7 kPa and fugacity 6738.9 kPa Under these conditions, one mole of water in liquid phase has a volume of 25.28 cm3 and that in vapour phase in 391.1 cm3.Fugacity of water (in kPa) at 9000 kPa will be (A) 6738.9 (B) 6753.5 (C) 7058.3 (D) 9000

Last Answer : (B) 6753.5

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

Last Answer : Ans: c

Description : From the steam table, determine the average constant pressure specific heat (c) of steam at 10 kPa and45.8 ˚C  A.1.79 kJ/ kg-˚C  B.10.28 kJ/ kg-˚C  C.30.57 kJ/ kg-˚C  D. 100.1 kJ/ kg-˚C Formula: h = c T ∆ ∆ From the steam table At 47.7 ˚C h= 2588.1 kJ/ kg At 43.8 ˚C h= 2581.1 kJ/ kg

Last Answer : 1.79 kJ/ kg-˚C

Description : Humidification is the process of addition moisture in air at A. constant wet bulb temperature B. constant dry bulb temperature C. constant latent heat D. none of the above

Last Answer : ANSWER : B

Description : A Mixture of dry air and water,the formation of fog starts when, A. air temperature is equal to the dew point temperature B. air temperature is greater than the dew point temperature C. both a. and b. D. none of the above

Last Answer : ANSWER : A