With the help of suitable diagram, explain how humidity is measured with dry and wet bulb thermometer.

With the help of suitable diagram, explain how humidity is measured with dry and wet bulb thermometer.
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Explanation:- 1. A psychrometer, or wet-and-dry-bulb thermometer, consists of two thermometers, one that is dry and one that is kept moist with distilled water on a sock or wick. The two thermometers are thus called the dry-bulb and the wet-bulb. At temperatures above the freezing point of water, evaporation of water from the wick lowers the temperature, so that the wet-bulb thermometer usually shows a lower temperature than that of the dry-bulb thermometer. When the air temperature is below freezing, however, the wet-bulb is covered with a thin coating of ice and may be warmer than the dry bulb. 2 .Relative humidity is computed from the ambient temperature as shown by the drybulb thermometer and the difference in temperatures as shown by the wet-bulb and dry-bulb thermometers. Psychrometers are commonly used in meteorology, and in the HVAC industry for proper refrigerant charging of residential and commercial air conditioning systems. 

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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

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

The wet bulb temperature is lower in dry air than in wet air at the same temperature. A dry bulb thermometer registers a higher temperature than a wet bulb thermometer except at __________ percent relative humidity. (A) 0 (B) 100 (C) 50 (D) None of these

Description : The wet bulb temperature is lower in dry air than in wet air at the same temperature. A dry bulb thermometer registers a higher temperature than a wet bulb thermometer except at __________ percent relative humidity. (A) 0 (B) 100 (C) 50 (D) None of these

Last Answer : Option B

What is Psychrometer ? Explain dry bulb thermometer & wet bulb thermometer.

Description : What is Psychrometer ? Explain dry bulb thermometer & wet bulb thermometer.

Last Answer : Psychrometers are instruments used for measuring relative humidity. Explanation:- A psychrometer, or wet-and-dry-bulb thermometer, consists of two thermometers, one that is dry and one ... thermometer and the difference in temperatures as shown by the wet-bulb and dry-bulb thermometers.

A psychrometer (pron: si-'kro-me-ter) is used to measure humidity. It consists of two thermometers, one of which is wetted. The water is allowed to evaporate. Which thermometer reads the higher temperature. w) the wet one x) the dry one

Description : A psychrometer (pron: si-'kro-me-ter) is used to measure humidity. It consists of two thermometers, one of which is wetted. The water is allowed to evaporate. Which thermometer reads the higher temperature. w) the wet one x) the dry one 

Last Answer : ANSWER: X -- THE DRY ONE 

Combination of Dry bulb and Wet bulb thermometer used for

Description : Combination of Dry bulb and Wet bulb thermometer used for

Last Answer : Ans. Relative Humidity

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

When the difference in the temperature of the wet-bulb thermometer and dry-bulb thermometer is large, what does it indicate about the air? w) it is very dry x) it is nearly saturated y) it is very warm z) it is very cold

Description : When the difference in the temperature of the wet-bulb thermometer and dry-bulb thermometer is large, what does it indicate about the air? w) it is very dry x) it is nearly saturated y) it is very warm z) it is very cold

Last Answer : ANSWER: W -- IT IS VERY DRY

What is the relative humidity when the dry bulb temperature is 16 and the wet bulb is 14 celcius?

Description : What is the relative humidity when the dry bulb temperature is 16 and the wet bulb is 14 celcius?

Last Answer : Feel Free to Answer

Sling psychrometer is used to measure A. only dry bulb temperature B. only wet bulb temperature C. dry and wet bulb temperature D. relative humidity

Description : Sling psychrometer is used to measure A. only dry bulb temperature B. only wet bulb temperature C. dry and wet bulb temperature D. relative humidity

Last Answer : ANSWER : C

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 temperature c) equal to the wet bulb temperature divided by the dry bulb temperature d) the ratio of the mass of water vapour divided by the mass of dry air e) the ratio of the mass of water vapour divided by the mass of wet air

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

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

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

Which of the following can be calculated theoretically using steam table and Dalton's law of partial pressure; if the relative humidity and dry bulb temperature of moist air is known? (A) Dew point (B) Humidity ratio (C) Wet bulb temperature (D) None of these

Description : Which of the following can be calculated theoretically using steam table and Dalton's law of partial pressure; if the relative humidity and dry bulb temperature of moist air is known? (A) Dew point (B) Humidity ratio (C) Wet bulb temperature (D) None of these

Last Answer : (C) Wet bulb temperature

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

During sensible heating of humid air (A) Relative humidity increases (B) Dew point remains constant (C) Dry bulb & wet bulb temperature increases (D) Both 'b' & 'c'

Description : During sensible heating of humid air (A) Relative humidity increases (B) Dew point remains constant (C) Dry bulb & wet bulb temperature increases (D) Both 'b' & 'c'

Last Answer : (D) Both 'b' & 'c'

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

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

__________ remains constant during the adiabatic cooling of moist air. (A) Wet bulb temperature (B) Dry bulb temperature (C) Relative humidity (D) Specific humidity

Description : __________ remains constant during the adiabatic cooling of moist air. (A) Wet bulb temperature (B) Dry bulb temperature (C) Relative humidity (D) Specific humidity

Last Answer : Option A

The dew point temperature lines on psychrometric charts are straight inclined sloping downwards to the right. When relative humidity of moist air is 100%, then (A) Wet bulb temperature=dry bulb temperature (B) Wet bulb temperature=dew point temperature (C) Saturation temperature=dew point temperature (D) All 'a', 'b' & 'c

Description : The dew point temperature lines on psychrometric charts are straight inclined sloping downwards to the right. When relative humidity of moist air is 100%, then (A) Wet bulb temperature=dry bulb temperature (B) ... temperature (C) Saturation temperature=dew point temperature (D) All 'a', 'b' & 'c

Last Answer : Option D

A sling psychrometer is used to measure : a) only dry bulb temperature b) only wet bulb temperature c) both a & b d) relative humidity

Description : A sling psychrometer is used to measure : a) only dry bulb temperature b) only wet bulb temperature c) both a & b d) relative humidity

Last Answer : c) both a & b

Explain the concept of dry bulb, wet bulb temperature. How they are measured?

Description : Explain the concept of dry bulb, wet bulb temperature. How they are measured?

Last Answer : Dry Bulb Temperature of Air (DBT) The temperature of the air measured by the ordinary thermometer is called as the dry bulb temperature of air, commonly referred as DBT. When ordinary thermometer is ... bulb temperature of air. The difference between the DBT and WBT is called as wet bulb depression.

When dry bulb temperature (DBT) and wet bulb temperature (WBT) are measured, greater the difference between DBT and WBT, A. greater the amount of water vapour held in the mixture B. smaller the amount of water vapour held in the mixture C. same the amount of water vapour held in the mixture D. none of the above

Description : When dry bulb temperature (DBT) and wet bulb temperature (WBT) are measured, greater the difference between DBT and WBT, A. greater the amount of water vapour held in the mixture B. smaller the amount of ... the mixture C. same the amount of water vapour held in the mixture D. none of the above

Last Answer : ANSWER : B

Which temperature can be measured by an instrument called psychrometer? A. dry bulb temperature B. wet bulb temperature C. both a. and b. D. none of the above

Description : Which temperature can be measured by an instrument called psychrometer? A. dry bulb temperature B. wet bulb temperature C. both a. and b. D. none of the above

Last Answer : ANSWER : C

For the case of flow of air past a wet bulb thermometer (air water vapour system), the approximate value of h2 /ky .Cz is around (A) 0.60 (B) 0.24 (C) 1 (D) 0.72

Description : For the case of flow of air past a wet bulb thermometer (air water vapour system), the approximate value of h2 /ky .Cz is around (A) 0.60 (B) 0.24 (C) 1 (D) 0.72

Last Answer : (C) 1

The Stevenson screen contains all of these EXCEPT: A. Wet bulb thermometer B. Maximum thermometer C. Ordinary thermometer D. Anemometer (Answer)

Description : The Stevenson screen contains all of these EXCEPT: A. Wet bulb thermometer B. Maximum thermometer C. Ordinary thermometer D. Anemometer (Answer)

Last Answer : D. Anemometer (Answer)

How Do You Measure Temperature In A Wet Bulb Thermometer?

Description : How Do You Measure Temperature In A Wet Bulb Thermometer?

Last Answer : Wet bulb temperature is measured in a wet bulb thermometer by covering the bulb with a wick and wetting it with water. It corresponds to the dew point temperature and relative humidity.

Humidity is measured by (1) Lactometer (2) Polarimeter (3) Thermometer (4) Hygrometer

Description : Humidity is measured by (1) Lactometer (2) Polarimeter (3) Thermometer (4) Hygrometer

Last Answer : Hygrometer

Describe with neat diagram, how temperature is measured by Gas filled thermometer.

Description : Describe with neat diagram, how temperature is measured by Gas filled thermometer.

Last Answer : Explanation:- If volume of a gas is maintained at constant and If a certain volume of inert gas is enclosed in a bulb, capillary and bourdon tube, the most of the gas in the bulb, then the ...   Name of the gases used in Gas filled thermometers.  1. Nitrogen 2. Helium 3. Inert Gas 

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

Which of the following remains constant during evaporative cooling process with recirculated water supply? (A) Relative humidity (B) Partial pressure of vapour (C) Wet bulb temperature (D) None of these

Description : Which of the following remains constant during evaporative cooling process with recirculated water supply? (A) Relative humidity (B) Partial pressure of vapour (C) Wet bulb temperature (D) None of these

Last Answer : (C) Wet bulb temperature

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

During dehumidification of unsaturated air wet bulb temperature & partial pressure of vapor are not constant. However, during evaporative cooling process with recirculated water supply, the __________ remains constant. (A) Wet bulb temperature (B) Partial pressure of water vapor (C) Relative humidity (D) None of these

Description : During dehumidification of unsaturated air wet bulb temperature & partial pressure of vapor are not constant. However, during evaporative cooling process with recirculated water supply, the __________ remains ... pressure of water vapor (C) Relative humidity (D) None of these

Last Answer : (A) Wet bulb temperature

Which of the following decreases during evaporative cooling process with recirculated water supply? (A) Wet bulb temperature (B) Relative humidity (C) Partial pressure of vapour (D) None of these

Description : Which of the following decreases during evaporative cooling process with recirculated water supply? (A) Wet bulb temperature (B) Relative humidity (C) Partial pressure of vapour (D) None of these

Last Answer : (D) None of these

Pick out the wrong statement (A) A horizontal line on the humidity chart indicates the temperature changes at constant molal humidity (B) When water is cooled from 80 to 70°C by exposure to the air with a wet bulb temperature of 60°C, then both the approach & the range would be 10°C (C) For unsaturated air-water vapor mixture at atmospheric conditions, the wet bulb temperature & adiabatic cooling lines are the same (D) Relative saturation of unsaturated mixture of water vapor & air cannot be increased by either reducing the mixture temperature or by increasing the total pressure

Description : Pick out the wrong statement (A) A horizontal line on the humidity chart indicates the temperature changes at constant molal humidity (B) When water is cooled from 80 to 70°C by exposure ... & air cannot be increased by either reducing the mixture temperature or by increasing the total pressure

Last Answer : (D) Relative saturation of unsaturated mixture of water vapor & air cannot be increased by either reducing the mixture temperature or by increasing the total pressure

Pick out the wrong statement pertaining to the cooling towers. (A) In case of induced draft cooling tower, the fan is placed at the top of the tower (B) Effectiveness of forced draft cooling tower is reduced by the recirculation of the humid and hot discharged air (C) A natural draft cooling tower is recommended to be used, when the air humidity is low and air temperature is also low (D) Effectiveness of a mechanical draft cooling tower is reduced with increase in air wet-bulb temperature

Description : Pick out the wrong statement pertaining to the cooling towers. (A) In case of induced draft cooling tower, the fan is placed at the top of the tower (B) Effectiveness of ... Effectiveness of a mechanical draft cooling tower is reduced with increase in air wet-bulb temperature

Last Answer : (D) Effectiveness of a mechanical draft cooling tower is reduced with increase in air wet-bulb temperature

Which of the following increases during evaporative cooling process with recirculated water supply? (A) Wet bulb temperature (B) Relative humidity (C) Partial pressure of vapour (D) Both (B) and (C)

Description : Which of the following increases during evaporative cooling process with recirculated water supply? (A) Wet bulb temperature (B) Relative humidity (C) Partial pressure of vapour (D) Both (B) and (C)

Last Answer : (D) Both (B) and (C)

During sensible cooling process (A) Relative humidity decreases (B) Relative humidity increases (C) Wet bulb temperature decreases (D) Both (B) and (C)

Description : During sensible cooling process (A) Relative humidity decreases (B) Relative humidity increases (C) Wet bulb temperature decreases (D) Both (B) and (C)

Last Answer : (D) Both (B) and (C)

At 100% relative humidity, the dew point temperature of moist air is (A) Less than the wet bulb temperature (B) More than the wet bulb temperature (C) Equal to the wet bulb temperature (D) Equal to the ambient temperature

Description : At 100% relative humidity, the dew point temperature of moist air is (A) Less than the wet bulb temperature (B) More than the wet bulb temperature (C) Equal to the wet bulb temperature (D) Equal to the ambient temperature

Last Answer : (B) More than the wet bulb temperature

Explain the following a) Dry Bulb Temperature and Wet bulb Temperature b) Maximum Demand and Power Factor c) Gross Calorific Value & Net Calorific Value d) 5S & Return of Investment (ROI) e) CUSUM

Description : Explain the following a) Dry Bulb Temperature and Wet bulb Temperature b) Maximum Demand and Power Factor c) Gross Calorific Value & Net Calorific Value d) 5S & Return of Investment (ROI) e) CUSUM

Last Answer : a) Dry Bulb Temperature and Wet bulb Temperature Dry bulb Temperature is an indication of the sensible heat content of air-water vapour  mixtures Wet bulb Temperature is a measure of ... of capital cost. This is a broad indicator of the annual return expected from initial capital investment

Explain the following terms: (i) Dry Bulb Temperature (ii) Wet Bulb Temperature.

Description : Explain the following terms: (i) Dry Bulb Temperature (ii) Wet Bulb Temperature.

Last Answer : Dry bulb temperature: Temperature recorded by ordinary thermometer is called dry bulb temperature. Measurement of DBT: The temperature of air measured by an ordinary thermometer without cover of bulb by ... or possible rain. One condition for rain is abundance of water vapour in the atmosphere.

Define temperature. Explain dry bulb temperature and wet bulb temperature.

Description : Define temperature. Explain dry bulb temperature and wet bulb temperature.

Last Answer : Temperature: Temperature is a measure of hotness or coldness of a body. Dry bulb temperature: Temperature recorded by ordinary thermometer is called dry bulb temperature. Wet bulb temperature: ... weather or possible rain. One condition for rain is abundance of water vapour in the atmosphere.

What is the dew-point when the dry bulb temperature is 20C and the relative humidity is 17?

Description : What is the dew-point when the dry bulb temperature is 20C and the relative humidity is 17?

Last Answer : at 17% relative humidity the dew point is -5.8C at a dry bulb of20C

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

Humidity chart is useful for the solution of problems concerning condensation, vaporisation and air conditioning. At a given dry bulb temperature, value of humidity obtained from the humidity chart directly, is in terms of __________ humidity. (A) Molal (B) Relative (C) Percentage (D) None of these

Description : Humidity chart is useful for the solution of problems concerning condensation, vaporisation and air conditioning. At a given dry bulb temperature, value of humidity obtained from the humidity chart directly, is in ... (A) Molal (B) Relative (C) Percentage (D) None of these

Last Answer : (A) Mola

Which of the following processes is followed by unsaturated air (with dry bulb temperature 12°C and relative humidity 47%) passing through water spray washer (temperature of water being constant at 40°C? (A) Humidification only (B) Heating only (C) Both heating and humidification (D) Evaporative cooling

Description : Which of the following processes is followed by unsaturated air (with dry bulb temperature 12°C and relative humidity 47%) passing through water spray washer (temperature of water being constant at 40°C ... (B) Heating only (C) Both heating and humidification (D) Evaporative cooling

Last Answer : (C) Both heating and humidification

. In chemical dehumidification of air (A) Both specific humidity & dry bulb temperature increases (B) Both specific humidity & dry bulb temperature decreases (C) Specific humidity decreases & dry bulb temperature increases (D) Specific humidity increases & dry bulb temperature decreases

Description : . In chemical dehumidification of air (A) Both specific humidity & dry bulb temperature increases (B) Both specific humidity & dry bulb temperature decreases (C) Specific humidity decreases & dry bulb temperature increases (D) Specific humidity increases & dry bulb temperature decreases

Last Answer : (C) Specific humidity decreases & dry bulb temperature increases

At any point on the saturation curve in psychometric chart, the dry bulb temperature is always A. less than the corresponding wet bulb temperature B. more than the corresponding wet bulb temperature C. equal to the corresponding wet bulb temperature D. cannot predict

Description : At any point on the saturation curve in psychometric chart, the dry bulb temperature is always A. less than the corresponding wet bulb temperature B. more than the corresponding wet bulb temperature C. equal to the corresponding wet bulb temperature D. cannot predict

Last Answer : 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

__________ 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