What has to happen for Condensation to occur in nature air must be cooled to its dew point and there must be some kind of solid surface present true or false?

What has to happen for Condensation to occur in nature air must be cooled to its dew point and there must be some kind of solid surface present true or false?
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Moist air is cooled along the line of constant __________ , when it is passed over a cold & dry cooling coil, such that no condensation occurs? (A) Enthalpy (B) Relative humidity (C) Wet bulb temperature (D) Dew point temperature

Description : Moist air is cooled along the line of constant __________ , when it is passed over a cold & dry cooling coil, such that no condensation occurs? (A) Enthalpy (B) Relative humidity (C) Wet bulb temperature (D) Dew point temperature

Last Answer : (D) Dew point temperature

_________ is the temperature to which the air must be cooled, at constant pressure, to produce saturation.  a. relative humidity  b. triple point temperature  c. dew point  d. critical point

Description : _________ is the temperature to which the air must be cooled, at constant pressure, to produce saturation.  a. relative humidity  b. triple point temperature  c. dew point  d. critical point

Last Answer : dew point

The temperature to which a vapour gas mixture must be cooled (at varying humidity) to become saturated is called the __________ temperature. (A) Dew point (B) Wet bulb (C) Dry bulb (D) None of these

Description : The temperature to which a vapour gas mixture must be cooled (at varying humidity) to become saturated is called the __________ temperature. (A) Dew point (B) Wet bulb (C) Dry bulb (D) None of these

Last Answer : (D) None of these

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

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

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 humidified (B) And dehumidified with increase in wet bulb temperature (C) At the same relative humidity (D) And dehumidified with decrease in wet bulb temperature

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

The minimum temperature to which the water can be cooled in a cooling tower is the __________ temperature of air. (A) Ambient (B) Dry bulb (C) Dew point (D) Wet bulb

Description : The minimum temperature to which the water can be cooled in a cooling tower is the __________ temperature of air. (A) Ambient (B) Dry bulb (C) Dew point (D) Wet bulb

Last Answer : C) Dew point

Minimum temperature upto which water can be theoretically cooled down in the cooling tower by evaporative cooling is equal to the __________ temperature of air. (A) Wet bulb (B) Dry bulb (C) Saturation (D) Dew point

Description : Minimum temperature upto which water can be theoretically cooled down in the cooling tower by evaporative cooling is equal to the __________ temperature of air. (A) Wet bulb (B) Dry bulb (C) Saturation (D) Dew point

Last Answer : Option 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

__________ 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

Water vapour beyond the dew point result in A. Precipitation B. Hailstorm C. Condensation D. Formation of ice

Description : Water vapour beyond the dew point result in A. Precipitation B. Hailstorm C. Condensation D. Formation of ice

Last Answer : ANSWER: C

On large generators, space heaters are used to ____________. A. keep the machine at ambient tmperature of the machinery space B. maintain rotor and stator winding temperatures above the dew point to prevent the formation of condensation C. prevent condensation in the lube oil D. prevent electrolysis due to condensation in the bearings

Description : On large generators, space heaters are used to ____________. A. keep the machine at ambient tmperature of the machinery space B. maintain rotor and stator winding temperatures above the dew point ... C. prevent condensation in the lube oil D. prevent electrolysis due to condensation in the bearings

Last Answer : Answer: B

Water vapour beyond the dew point result in-----? A. Precipitation B. Hailstorm C. Condensation (Answer) D. Formation of ice

Description : Water vapour beyond the dew point result in-----? A. Precipitation B. Hailstorm C. Condensation (Answer) D. Formation of ice

Last Answer : C. Condensation (Answer)

Condensation starts at ________ point. A Dew B Bubble C Triple D none of the mentioned

Description : Condensation starts at ________ point. A Dew B Bubble C Triple D none of the mentioned

Last Answer : A Dew

Condensation starts ________ point. A] Dew point B] Bubble point C] Triple point D] None of the mentioned

Description : Condensation starts ________ point. A] Dew point B] Bubble point C] Triple point D] None of the mentioned

Last Answer : A] Dew point

In case of a super-cooled solution, which is on the verge of crystallisation, the free energy of the solution as compared to that of the solid is (A) More (B) Less (C) Same (D) More or less; depends on the nature of solution

Description : In case of a super-cooled solution, which is on the verge of crystallisation, the free energy of the solution as compared to that of the solid is (A) More (B) Less (C) Same (D) More or less; depends on the nature of solution

Last Answer : (A) More

The most conducive surface for dropwise condensation to occur is the __________ surface. (A) Coated (B) Oily (C) Glazed & polished (D) Smooth

Description : The most conducive surface for dropwise condensation to occur is the __________ surface. (A) Coated (B) Oily (C) Glazed & polished (D) Smooth

Last Answer : (B) Oily

What would happen to the height of a cloud base if the dew point temperature or lower?

Description : What would happen to the height of a cloud base if the dew point temperature or lower?

Last Answer : Need answer

What would happen if the air inside a hot air balloon cooled down?

Description : What would happen if the air inside a hot air balloon cooled down?

Last Answer : What is the answer ?

What happen with the air in a soccer ball with a cooled?

Description : What happen with the air in a soccer ball with a cooled?

Last Answer : What is the answer ?

What happen with the air in a soccer ball with a cooled and heated?

Description : What happen with the air in a soccer ball with a cooled and heated?

Last Answer : The air pressure goes down when cooled, goes up when heated. Asoccer ball left outdoors in freezing weather does not have muchbounce. Left outside on a hot day, has a lot of bounce.

What happen with the air in a soccer ball with a cooled and heated?

Description : What happen with the air in a soccer ball with a cooled and heated?

Last Answer : The air pressure goes down when cooled, goes up when heated. Asoccer ball left outdoors in freezing weather does not have muchbounce. Left outside on a hot day, has a lot of bounce.

What is the amount of heat needed to turn 1 kg of the substance at its melting point from the solid to liquid state?  A. Heat of fusion  B. Heat of vaporation  C. Heat of condensation  D. Heat of fission

Description : What is the amount of heat needed to turn 1 kg of the substance at its melting point from the solid to liquid state?  A. Heat of fusion  B. Heat of vaporation  C. Heat of condensation  D. Heat of fission

Last Answer : Heat of fusion

Which of the following situations can be approximated to a steady state heat transfer system? (A) A red hot steel slab (having outside surface temperature as 1300°C) exposed to the atmospheric air at 35°C (B) 10 kg of dry saturated steam at 8 kgf/cm2 flowing through a short length of stainless steel pipe exposed to atmospheric air at 35°C (C) Boiling brine kept in open vessel when the bottom surface temperature of the vessel is maintained constant at 180°C (D) A sub-cooled refrigerant liquid at 8°C flowing at the rate of 6 Kg/minute through a copper pipe exposed to atmospheric air at 35°C

Description : Which of the following situations can be approximated to a steady state heat transfer system? (A) A red hot steel slab (having outside surface temperature as 1300°C) exposed to the atmospheric air at ... flowing at the rate of 6 Kg/minute through a copper pipe exposed to atmospheric air at 35°C

Last Answer : (B) 10 kg of dry saturated steam at 8 kgf/cm2 flowing through a short length of stainless steel pipe exposed to atmospheric air at 35°C

In nature water may occur as (A) Liquid (B) Solid (C) Vapours (D) All the above

Description : In nature water may occur as (A) Liquid (B) Solid (C) Vapours (D) All the above

Last Answer : Answer: Option D

In sub-cooled boiling, (A) Temperature of the heating surface is less than the boiling point of the liquid (B) Temperature of the heating surface is more than the boiling point of the liquid (C) Bubbles from heating surface are absorbed by the mass of the liquid (D) Very large vapour space is necessary

Description : In sub-cooled boiling, (A) Temperature of the heating surface is less than the boiling point of the liquid (B) Temperature of the heating surface is more than the boiling point of the liquid (C) ... from heating surface are absorbed by the mass of the liquid (D) Very large vapour space is necessary

Last Answer : (B) Temperature of the heating surface is more than the boiling point of the liquid

(4) Liquid Hydrogen + Liquid Oxygen Explanation: LOX and liquid hydrogen, used in the Space Shuttle orbiter, the Centaur upper stage of the Atlas V, Saturn V upper stages, the newer Delta IV rocket, the H-IIA rocket, and most stages of the European Ariane rockets. Liquid fueled rocicets have higher specific impulse than solid rockets and are capable of being throttled, shut down, and restarted. Only the combustion chamber of a liquid fueled rocket needs to withstand high combustion pressures and temperatures and they can be regeneratively cooled by the liquid propellant.

Description : (4) Liquid Hydrogen + Liquid Oxygen Explanation: LOX and liquid hydrogen, used in the Space Shuttle orbiter, the Centaur upper stage of the Atlas V, Saturn V upper stages, the ... to withstand high combustion pressures and temperatures and they can be regeneratively cooled by the liquid propellant.

Last Answer : The BOD values of water indicate the (1) amount of organic debris (2) amount of oxygen used for biochemical oxidation (3) amount of oxygen used for biochemical reduction (4) amount of ozone used for biochemical oxidation

Glass is - (1) Super cooled liquid (2) Crystalline solid (3) Liquid crystal (4) None of these

Description : Glass is - (1) Super cooled liquid (2) Crystalline solid (3) Liquid crystal (4) None of these

Last Answer : (1) Super cooled liquid Explanation: Glass is sometimes called a Super cooled liquid because it does not form a crystalline structure, but instead forms an amorphous solid that allows molecules in the material to continue to move.

In direct cooled system using hydrogen both stator and rotor conductors are made (a) solid (b) hollow (c) perforated (d) any ofthe above

Description : In direct cooled system using hydrogen both stator and rotor conductors are made (a) solid (b) hollow (c) perforated (d) any ofthe above

Last Answer : (b) hollow

What happens its dew point as an air mass increases in temperature?

Description : What happens its dew point as an air mass increases in temperature?

Last Answer : As an air mass increases in temperature it's dew point falls(becomes a smaller number)

. The most suitable equipment for removing the fine dust particle (< 1 micron dia.) from air below its dew point will be a/an (A) Bag filter (B) Electrostatic precipitator (C) Cyclone separator (D) Wet scrubber

Description : . The most suitable equipment for removing the fine dust particle (< 1 micron dia.) from air below its dew point will be a/an (A) Bag filter (B) Electrostatic precipitator (C) Cyclone separator (D) Wet scrubber

Last Answer : (B) Electrostatic precipitator

Dry bulb temperature of unsaturated air is more than its __________ temperature. (A) Dew point (B) Wet bulb (C) Both 'a' & 'b' (D) Neither 'a' nor 'b

Description : Dry bulb temperature of unsaturated air is more than its __________ temperature. (A) Dew point (B) Wet bulb (C) Both 'a' & 'b' (D) Neither 'a' nor 'b

Last Answer : (C) Both 'a' & 'b

A mixture of 10% C6H6 vapour in air at 25°C and 750 mm Hg has a dew point of 20°C. Its dew point at 30°C and 700 mm Hg will be around __________ °C. (A) 21.7 (B) 20 (C) 27.3 (D) 18.7

Description : A mixture of 10% C6H6 vapour in air at 25°C and 750 mm Hg has a dew point of 20°C. Its dew point at 30°C and 700 mm Hg will be around __________ °C. (A) 21.7 (B) 20 (C) 27.3 (D) 18.7

Last Answer : (D) 18.7

During sensible cooling of air, its wet bulb temperature (A) Decreases but dew point remains constant (B) Increases but dew point remains constant (C) Increases & the dew point decreases (D) Decreases & the dew point increases

Description : During sensible cooling of air, its wet bulb temperature (A) Decreases but dew point remains constant (B) Increases but dew point remains constant (C) Increases & the dew point decreases (D) Decreases & the dew point increases

Last Answer : (B) Increases but dew point remains constant

The dew point of moist air becomes __________ with decrease in its relative humidity. (A) Less than the wet bulb temperature (B) More than the wet bulb temperature (C) More than the dry bulb temperature (D) Equal to wet bulb temperature

Description : The dew point of moist air becomes __________ with decrease in its relative humidity. (A) Less than the wet bulb temperature (B) More than the wet bulb temperature (C) More than the dry bulb temperature (D) Equal to wet bulb temperature

Last Answer : Option A

In a gas-liquid shell and tube heat exchanger, the(A) Presence of a non-condensable gas decreases the condensing film co￾efficient (B) Gases under high pressure are routed through the tube side, because high pressure gases are corrosive in nature (C) Gases to be heated/cooled is normally routed through the shell side, because the corrosion caused by the cooling water or steam condensate remain localised to the tubes (D) All 'a', 'b' & 'c'

Description : In a gas-liquid shell and tube heat exchanger, the (A) Presence of a non-condensable gas decreases the condensing film co￾efficient (B) Gases under high pressure are routed through the tube side, because high pressure ... water or steam condensate remain localised to the tubes (D) All 'a', 'b' & 'c'

Last Answer : (D) All 'a', 'b' & 'c'

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

What relationship would you expect to find between the air temperature and dew point temperature at ground level if an area is covered in fog?

Description : What relationship would you expect to find between the air temperature and dew point temperature at ground level if an area is covered in fog?

Last Answer : The relationship that you expect to find between the air temperature and dew point temperature at ground level if the area is covered by fog is the temperatures of th air and the dew point would be very close in value.

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

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

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

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

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

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

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

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 at a particular humidity is heated in a furnace. The new dew point (A) Decreases (B) Increases (C) Depends on the extent of heating (D) Remain unchanged

Description : Air at a particular humidity is heated in a furnace. The new dew point (A) Decreases (B) Increases (C) Depends on the extent of heating (D) Remain unchanged

Last Answer : (B) Increases

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. The humidity of air sample expressed as kg of water vapour/kg of dry air is: (A) 0.048 (B) 0.079 (C) 0.122 (D) 0.152

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

Dew point of an air-water vapor mixture (A) Decreases with decrease in pressure (B) At constant humidity & total pressure is fixed (C) Corresponding to any point on the humidity chart is obtained by projecting a line through this point parallel to the temperature axis and to the saturation curve (D) All 'a', 'b' & 'c'

Description : Dew point of an air-water vapor mixture (A) Decreases with decrease in pressure (B) At constant humidity & total pressure is fixed (C) Corresponding to any point on the humidity chart is obtained by projecting a ... to the temperature axis and to the saturation curve (D) All 'a', 'b' & 'c'

Last Answer : (D) All 'a', 'b' & 'c'