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 and pressure c. . Temperature that air will begin to evaporate moisture d. . Temperature at which air, upon cooling, becomes saturated, causing moisture to condense should the temperature drop further e. . Atmospheric pressure at which air will condense moisture

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 and pressure c. . Temperature that air will begin to evaporate moisture d. . Temperature at which air, upon cooling, becomes saturated, causing moisture to condense should the temperature drop further e. . Atmospheric pressure at which air will condense moisture
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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 condense out of the air d. Pressure below which water vapour will start to condense out of the air e. Temperature at which water will start to evaporate

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

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 to find the relative humidity d. The temperature of the air measured with an ordinary thermometer e. The dew point temperature

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

Absolute or specific humidity is a) the actual mass of moisture present in a specific amount of air b) the maximum mass of moisture that a specific amount of air can hold c) the ratio of the mass of moisture contained in a specific amount of air to the maximum amount of moisture this specific amount of air can contain d) the mass of moisture present in a specific amount of air at that absolute temperature e) a specific amount of air saturated with moisture

Description : Absolute or specific humidity is a) the actual mass of moisture present in a specific amount of air b) the maximum mass of moisture that a specific amount of air can hold c) the ratio of ... a specific amount of air at that absolute temperature e) a specific amount of air saturated with moisture

Last Answer : ANSWER : A

The dew point temperature is less than the wet bulb temperature for A. saturated air B. unsaturated air C. both saturated and unsaturated air D. none of the above

Description : The dew point temperature is less than the wet bulb temperature for A. saturated air B. unsaturated air C. both saturated and unsaturated air D. none of the above

Last Answer : ANSWER : B

The term "relative humidity" applies to a) the percentage of moisture in the air as compared to the amount of moisture the air can hold at a specific temperature b) the weight of the moisture in the air c) the dryness fraction of the air d) the amount of moisture in the air e) the amount of humidity in the air

Description : The term "relative humidity" applies to a) the percentage of moisture in the air as compared to the amount of moisture the air can hold at a specific temperature b) the weight of the moisture in the air c) ... of the air d) the amount of moisture in the air e) the amount of humidity in the air

Last Answer : ANSWER : A

The temperature at which the air cannot hold all the water vapour mixed in it and some vapour starts condensing is called as A. humidification temperature B. dehumidification temperature C. dew point temperature D. none of the above

Description : The temperature at which the air cannot hold all the water vapour mixed in it and some vapour starts condensing is called as A. humidification temperature B. dehumidification temperature C. dew point temperature D. none of the above

Last Answer : ANSWER : C

Which one of the following methods can be adopted to obtain isothermal compression in an air compressor? A. Increasing the weight of the compressor B. Inter-stage heating C. Atmospheric cooling D. Providing appropriate dimensions to the cylinder

Description : Which one of the following methods can be adopted to obtain isothermal compression in an air compressor? A. Increasing the weight of the compressor B. Inter-stage heating C. Atmospheric cooling D. Providing appropriate dimensions to the cylinder

Last Answer : ANSWER : A

What is sensible cooling of air? A. the cooling in which sensible heat of air is removed in order to reduce temperature B. the cooling in which temperature of air is reduced without changing in its moisture content C. both a. and b. D. none of the above

Description : What is sensible cooling of air? A. the cooling in which sensible heat of air is removed in order to reduce temperature B. the cooling in which temperature of air is reduced without changing in its moisture content C. both a. and b. D. none of the above

Last Answer : ANSWER : C

n a chemical factory where dyes are made, wet cake at 30 OC consisting of 60% moisture is put in a dryer to obtain an output having only 5% moisture, at atmospheric pressure. In each batch about 120 kgs of material is dried. a. The quantity of moisture removed per batch. b. What is the total quantity ( sensible & latent) of heat required to evaporate the moisture, if the latent heat of water is 540 kcal/kg at atmospheric conditions, Ignore heat absorbed by the solids c. Find the quantity of steam required for the drying process (per batch), if steam at 4 kg/cm2 is used for generating hot air in the dryer and the dryer efficiency is 80%. Latent heat of steam at 4 kg/cm2 is 520 kcal/kg.

Description : n a chemical factory where dyes are made, wet cake at 30 OC consisting of 60% moisture  is put in a dryer to obtain an output having only 5% moisture, at atmospheric pressure. In  each batch about 120 ... dryer and the dryer efficiency  is 80%. Latent heat of steam at 4 kg/cm2 is 520 kcal/kg.

Last Answer : Given that   Qty of material dried per batch - 120 Kgs  Moisture at inlet - 60% a. The quantity of moisture removed per batch.  Water quantity in a wet batch - 120 x 0.6 = 72 Kgs.  Quantity of bone dry ... - 48/0.95 = 50.5 Kgs.  Equivalent water in a dry batch - 50.5 - 48 = 2.5 Kgs.

__________ is the temperature at which a gas-vapor mixture becomes saturated, when cooled at constant total pressure out of contact with a liquid. (A) Dew point (B) Bubble point (C) Dry bulb temperature (D) Wet bulb temperature

Description : __________ is the temperature at which a gas-vapor mixture becomes saturated, when cooled at constant total pressure out of contact with a liquid. (A) Dew point (B) Bubble point (C) Dry bulb temperature (D) Wet bulb temperature

Last Answer : (A) Dew point

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 temperature if the relative humidity is less than 100% c. The dew point temperature d. Always less than the dry-bulb temperature e. Not required to find the relative humidity

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

______________ is the temperature at which liquids start to boil or the temperature at which vapors begin to condense.  a. Saturation Temperature  b. Sub cooled Liquid  c. Compressed Liquid  d. Saturated Liquid

Description : ______________ is the temperature at which liquids start to boil or the temperature at which vapors begin to condense.  a. Saturation Temperature  b. Sub cooled Liquid  c. Compressed Liquid  d. Saturated Liquid

Last Answer : Saturation Temperature

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

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

Cavitation will begin when (A) The pressure at any location reaches an absolute pressure equal to the saturated vapour pressure of the liquid (B) Pressure becomes more than critical pressure (C) Flow is increased (D) Pressure is increased

Description : Cavitation will begin when (A) The pressure at any location reaches an absolute pressure equal to the saturated vapour pressure of the liquid (B) Pressure becomes more than critical pressure (C) Flow is increased (D) Pressure is increased

Last Answer : Answer: Option A

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

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

When the dew point temperature is equal to the air temperature then the relative humidity is A. 0% B. 50% C. 100% D. unpredictable

Description : When the dew point temperature is equal to the air temperature then the relative humidity is A. 0% B. 50% C. 100% D. unpredictable

Last Answer : ANSWER : C

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

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

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 : 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

Last Answer : ANSWER : B

Pick up the correct statement from the following: (A) Absolute humidity at a given temperature is equal to weight of moisture present in a unit volume (B) Relative humidity is the ratio of actual vapour pressure and saturation vapour pressure at the same temperature (C) Relative humidity is the ratio of the weight of the vapours present per unit volume to the weight of vapours which could be contained at the same temperature when fully saturated (D) All the above

Description : Pick up the correct statement from the following: (A) Absolute humidity at a given temperature is equal to weight of moisture present in a unit volume (B) Relative humidity is the ratio of ... of vapours which could be contained at the same temperature when fully saturated (D) All the above

Last Answer : Answer: Option D

Critical temperature is' the temperature above which (a) a gas will never liquefy (b) a gas will immediately liquefy (c) water will evaporate (d) water will never evaporate

Description : Critical temperature is' the temperature above which (a) a gas will never liquefy (b) a gas will immediately liquefy (c) water will evaporate (d) water will never evaporate

Last Answer : Ans: a

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 : 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

Last Answer : Ans: d

The horizontal line in psychrometric chart joining the change of state of air represents A. humidification B. sensible cooling or heating C. sensible cooling or heating with humidification D. sensible cooling or heating with dehumidification

Description : The horizontal line in psychrometric chart joining the change of state of air represents A. humidification B. sensible cooling or heating C. sensible cooling or heating with humidification D. sensible cooling or heating with dehumidification

Last Answer : ANSWER : B

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 the process (humidification or dehumidification) then, the sensible heat factor (H2 – H1) / (H3 – H1) represents the process of A. cooling and humidification B. cooling and dehumidification C. heating and humidification D. heating and dehumidification

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

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

Description : 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 ... pressure at sea level or 101.325 kPa e. Volume of 1 kg of air at 15°C and 100 kPa

Last Answer : Answer: D

When dew point la reached it is said that at that temperature (a) the atmosphere is said to be saturated with water vapour (b) the relative humidity of the atmosphere is 100% (c) the atmosphere can hold no more water vapour (d) All the above

Description : When dew point la reached it is said that at that temperature (a) the atmosphere is said to be saturated with water vapour (b) the relative humidity of the atmosphere is 100% (c) the atmosphere can hold no more water vapour (d) All the above

Last Answer : Ans: (a)

In psychrometric chart, dew point temperature lines are A. horizontal B. vertical C. curved D. straight lines slopping downwards to the right

Description : In psychrometric chart, dew point temperature lines are A. horizontal B. vertical C. curved D. straight lines slopping downwards to the right

Last Answer : ANSWER : A

At 100% relative humidity, the wet bulb temperature is A. lower than the dew point temperature B. higher than the dew point temperature C. equal to the dew point temperature D. none of the above

Description : At 100% relative humidity, the wet bulb temperature is A. lower than the dew point temperature B. higher than the dew point temperature C. equal to the dew point temperature D. none of the above

Last Answer : ANSWER : C

When dry bulb temperature & wet bulb temperature of moist air is the same, it means that the (A) Partial pressure of water vapour is less than the total pressure (B) Humidity is < 100% & dew point temperature of air has not reached (C) Dew point temperature of air has not reached & air is not saturated fully (D) Air is fully saturated

Description : When dry bulb temperature & wet bulb temperature of moist air is the same, it means that the (A) Partial pressure of water vapour is less than the total pressure (B) Humidity is < 100% & dew ... Dew point temperature of air has not reached & air is not saturated fully (D) Air is fully saturated

Last Answer : (D) Air is fully saturated

A device for measuring relative humidity is called: a. A dew point analyzer b. An R. H. gauge c. An aspirating gauge d. A psychrometer e. A chronometer

Description : A device for measuring relative humidity is called: a. A dew point analyzer b. An R. H. gauge c. An aspirating gauge d. A psychrometer e. A chronometer

Last Answer : Answer: D

The temperature of air recorded by thermometer when the bulb is covered by a cotton wick saturated by water is called as A. dry bulb temperature B. wet bulb temperature C. stream temperature D. psychrometric temperature

Description : The temperature of air recorded by thermometer when the bulb is covered by a cotton wick saturated by water is called as A. dry bulb temperature B. wet bulb temperature C. stream temperature D. psychrometric temperature

Last Answer : ANSWER : B

With increase in absolute humidity, the dew point of an unsaturated mixture of air and water vapor (at constant pressure and temperature). (A) Increases (B) Remains unchanged (C) Decreases (D) Decreases linearly

Description : With increase in absolute humidity, the dew point of an unsaturated mixture of air and water vapor (at constant pressure and temperature). (A) Increases (B) Remains unchanged (C) Decreases (D) Decreases linearly

Last Answer : (A) Increases

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

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

At the boiling point of the liquid at the prevailing pressure, the saturated absolute humidity becomes (A) 1 (B) 0 (C) ∞ (D) None of these

Description : At the boiling point of the liquid at the prevailing pressure, the saturated absolute humidity becomes (A) 1 (B) 0 (C) ∞ (D) None of these

Last Answer : (C) ∞

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

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

What is The point at which the air becomes saturated with water molecules due to cooling is called .?

Description : What is The point at which the air becomes saturated with water molecules due to cooling is called .?

Last Answer : Feel Free to Answer

During the manufacture of sulphuric acid, the temperature of molten sulphur is not increased beyond 160°C, as (A) It is very corrosive at elevated temperature (B) Its viscosity is not reduced on further heating (hence pressure drop on pumping it, cannot be further reduced) (C) It decomposes on further increasing the temperature (D) None of these

Description : During the manufacture of sulphuric acid, the temperature of molten sulphur is not increased beyond 160°C, as (A) It is very corrosive at elevated temperature (B) Its viscosity is not reduced on ... be further reduced) (C) It decomposes on further increasing the temperature (D) None of these

Last Answer : (B) Its viscosity is not reduced on further heating (hence pressure drop on pumping it, cannot be further reduced)

Supercharging is the process of a. supplying the engine with air at a density greater than the density of the surrounding atmosphere b. providing forced cooling air c. injecting excess fuel d. raising the exhaust pressure

Description : Supercharging is the process of a. supplying the engine with air at a density greater than the density of the surrounding atmosphere b. providing forced cooling air c. injecting excess fuel d. raising the exhaust pressure

Last Answer : ANSWER a. supplying the engine with air at a density greater than the density of the surrounding atmosphere

Scavenging air in diesel engine means a. air used for combustion under pressure b. forced air for cooling the cylinder c. burnt air containing products of combustion d. air used for forcing burnt gases out of the engines cylinder during the exhaust stroke

Description : Scavenging air in diesel engine means a. air used for combustion under pressure b. forced air for cooling the cylinder c. burnt air containing products of combustion d. air used for forcing burnt gases out of the engines cylinder during the exhaust stroke

Last Answer : ANSWER d. air used for forcing burnt gases out of the engines cylinder during the exhaust stroke

In SI engines knocking can be reduced by (a) Increasing the compression ratio (b) Increasing the cooling water temperature (c) Retarding the spark advance (d) Increasing the inlet air temperature

Description : In SI engines knocking can be reduced by (a) Increasing the compression ratio (b) Increasing the cooling water temperature (c) Retarding the spark advance (d) Increasing the inlet air temperature

Last Answer : Ans :c

Choose the correct statement (a) A refrigerant should have low latent heat (b) If operating temperature of system is low, then refrigerant with low boiling point should be used (c) Pre-cooling and sub-cooling bf refrigerant are same (d) Superheat and sensible heat of a. refrigerant are same

Description : Choose the correct statement (a) A refrigerant should have low latent heat (b) If operating temperature of system is low, then refrigerant with low boiling point should be used (c) Pre-cooling and sub-cooling bf refrigerant are same (d) Superheat and sensible heat of a. refrigerant are same

Last Answer : Ans: b

Dew point temperature always gives an indication of the __________ of the moist air. (A) Dryness (B) Moisture content (C) Coolness (D) Latent heat

Description : Dew point temperature always gives an indication of the __________ of the moist air. (A) Dryness (B) Moisture content (C) Coolness (D) Latent heat

Last Answer : (B) Moisture content

What is the relative humidity for a saturated air? A. 0% B. 50% C. 100% D. cannot say

Description : What is the relative humidity for a saturated air? A. 0% B. 50% C. 100% D. cannot say

Last Answer : ANSWER : C

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

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

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 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

Last Answer : Ans: d

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

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

What is the degree of saturation? A. the ratio of the actual relative humidity to the saturated specific humidity at the same temperature B. the ratio of the actual specific humidity to the saturated specific humidity at the same temperature C. the ratio of the saturated specific humidity to the actual specific humidity at the same temperature D. none of the above

Description : What is the degree of saturation? A. the ratio of the actual relative humidity to the saturated specific humidity at the same temperature B. the ratio of the actual specific humidity to the ... specific humidity to the actual specific humidity at the same temperature D. none of the above

Last Answer : ANSWER : B

Represent generation of steam on H-S diagram. Show constant dryness fraction lines, constant temperature lines, saturated line and superheated region on the same.

Description : Represent generation of steam on H-S diagram. Show constant dryness fraction lines, constant temperature lines, saturated line and superheated region on the same.

Last Answer : Represent generation of steam on H-S diagram. Show constant dryness fraction lines, constant temperature lines, saturated line and superheated region on the same.

Which is NOT a correct statement?  A. A superheated vapor will not condense when small amount of heat re removed  B. An ideal gas is a gas that is not a superheated vapor  C. A saturated liquid can absorb as much heat as it can without vaporizing  D. Water at 1 atm and room temperature is subcooled

Description : Which is NOT a correct statement?  A. A superheated vapor will not condense when small amount of heat re removed  B. An ideal gas is a gas that is not a superheated vapor  C. A saturated ... absorb as much heat as it can without vaporizing  D. Water at 1 atm and room temperature is subcooled

Last Answer : An ideal gas is a gas that is not a superheated vapor

Compressed air coming out from a punctured football  (a) becomes hotter  (b) becomes cooler1  (c) remains at the same temperature  (d) may become hotter or cooler depend-ing upon the humidity of the surround¬ing air  (e) attains atmospheric temperature.

Description : Compressed air coming out from a punctured football  (a) becomes hotter  (b) becomes cooler1  (c) remains at the same temperature  (d) may become hotter or cooler depend-ing upon the humidity of the surround¬ing air  (e) attains atmospheric temperature.

Last Answer : (b) becomes cooler1