1.a) Dew point and relative humidity are related to each other by the following expression:
where, Td is the dew point temperature (^{o}C) , T is the known temperature (^{o}C), and RH is the relative humidity
So, from the given values, at RH= 80%
= 21^{o}C
Similarly at RH= 50%
=15^{o}C
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1. (relative humidity) The partial pressure of water vapor in air is usually less than the...
15. The relative humidity of air equals the ratio of the partial pressure of water in the air to the equilibrium vapor pressure of water at the same temperature times 100%. If the relative humidity of the air is 56% and its temperature is 70°F, how many grams of water are present in a room measuring 15 ft x 10 ft x 11 ft? The vapor pressure of water at 68 °F is 17.54 torr. Show your work 15. The...
1) An air-water vapor mixture at 95°F has a relative humidity of 45%. Calculate the partial pressure of the water vapor and its dew-point temperature. (Hint: Psychrometric chart is really useful for this.)
The relative humidity of air equals the ratio of the partial pressure of water in the air to the equilibrium vapor pressure of water at the same temperature times 100%. If the relative humidity of the air is 58% and its temperature is 68 oF , how many moles of water are present in a room measuring 12 ft x 10 ft x 8 ft? The vapor pressure of water at 68 oF is 17.54 torr.
1 kg of atmospheric air initially at 30 ºc and 60% relative humidity is cooled slowly, at a constant pressure of 100 kPa, to a final temperature of 5 ºc. a. What is the saturation pressure of water at the initial temperature? b. What is the partial pressure of water vapor (vapor pressure) at the initial condition? c. What is the partial pressure of dry air at the initial condition? d. What is the initial humidity ratio? e. What is...
absolute humidity at atmospheric pressure at 27 C is 0.011 kg water / dry air determine: a. water vapor partial pressure (kPa) b. relative humidity (%) c. dew point temperature (C)
Assume all gases in this problem are ideal (a) If the partial pressure of water vapor is 31.8 torr, what is the dew point (in °C)? (760 torr- 1 atm 101,325 Pa) oC (b) On a warm day when the air temperature is 25°C and the dew point is 18°C, what are the partial pressure of the water in the air (in Pa) and the relative humidity? partial pressure R.H. Pa
Humidity is the amount of water vapor in the air at a given time. At warm temperatures, air can hold more moisture than it can at cold temperatures. Relative humidity is the amount of vapor the air is holding expressed as a percentage of the amount the air is capable of holding. For example, at 86 degrees Fahrenheit, air can hold a maximum of 30.4 grams of water per cubic meter. If the air at the same temperature is holding...
1) The air temperature is 15ºC. Determine the saturation vapor pressure at this temperature. If the dew point temperature is found to be 10ºC, determine the vapor pressure in the air, and calculate the relative humidity for both temperatures.
When the air temperature is high the human body uses sweating followed by evaporative cooling to control its temperature. This works only if the surrounding air is not already saturated with water, i.e., for relative humidities significantly below 100%. As it turns out, a 70.% relative humidity on a 90.ºF summer day in Florida will already feel very uncomfortable in the absence of a breeze. (a) Calculate the saturation (equilibrium) vapor pressure of water at 90.ºF and the actual vapor...
An air mass has a temperature of 18°C and a relative humidity of 42%. a) Determine the vapor pressure and saturation vapor pressure of the air. You can use tables from the Gupta text, or the equations presented in class (which are alsc in the evapotranspiration references on the camino site). Or you may use both to be more confident of your work. b) Assume the air mass rises and cools at a rate of -10 C/km. At what elevation...