单选题The latent heat of water vapor in air is dependent upon the （）Adry bulb temperatureBwet bulb temperatureCdew pointDdry point
单选题
The latent heat of water vapor in air is dependent upon the （）
A
dry bulb temperature
B
wet bulb temperature
C
dew point
D
dry point
参考解析
解析：
暂无解析
相关考题：
The temperature of the refrigerant in the evaporator coil depends mostly upon the ___.A.refrigerant pressure in the evaporatorB.cooling water temperature to the condenserC.heat load in the refrigerator compartmentD.solenoid valve in the liquid line
The heat identified by only a change in temperature is known asA.sensible heatB.latent heatC.total heatD.residual heat
The effective temperature of air is dependent upon ______. I. relative humidity II. air velocityA.I onlyB.II onlyC.Both I and IID.Neither I nor II
The heat gained per pound of refrigerant in the evaporator is known as the ______.A.latent heat of vaporizationB.sensible heatC.refrigerating effectD.specific heat of vaporization
The dew point is reached when the ______.A.temperature of the air equals the temperature of the seawaterB.atmospheric pressure is 14.7 lbs. per square inchC.relative humidity reaches 50%D.air becomes saturated with water vapor
单选题The exhaust pipe must be gas tight throughout its entire length otherwise（）.Abilge water may enter the exhaust pipeBentry of air may cause vapor lockCcarbon monoxide may enter the interior of the vesselDthe joint gaskets may be blown
单选题The latent heat of evaporation is dissipated in the （） in a compression refrigeration system.AevaporatorBcondenserCexpansion valveDcompressor
单选题The sum of the sensible heat and the latent heat of any substance is known as （）.Atotal heatBresidual heatCspecific heatDsuperheat
单选题In a refrigeration system, the refrigerant absorbs the latent heat of vaporization in the（）.AcompressorBcondenserCreceiverDevaporator
单选题Which of the following conditions could contribute to the cracking of a diesel engine cylinder head?（）ALeaking seal ringBInsufficient heat transfer from the exhaust valvesCBlock cooling water passages to the headDExcessive scavenging air provided to the engine
单选题The dew point temperature is（）.Aalways higher than the air temperatureBalways lower than the air temperatureCequal to the difference between the wet and dry bulb temperaturesDthe temperature at which the air is saturated with water vapor
单选题The rate of heat transfer in a water-tube auxiliary boiler can be increased by （）.Aoperating the boiler at less than normal water levelBinstalling fins on the firesides of water-tubesCincreasing the amount of excess air to the burnersDtreating the boiler water with chemical oxygen scavengers
单选题The power developed by a large slow-speed main propulsion diesel engine is dependent upon the （）Aquantity of air it takes in and retains in the cylinders during a given time periodBproportion of trapped air that is utilized in the combustion processCthermodynamic efficiency of the engine cycleDall of the above
单选题The dew point is reached when the（）.Atemperature of the air equals the temperature of the seawaterBatmospheric pressure is 14.7 lbs. per square inchCrelative humidity reaches 50%Dair becomes saturated with water vapor
单选题The temperature at which the air is saturated with water vapor and below which condensation of water vapor will occur is referred to as the（）.Aprecipitation pointBvapor pointCdew pointDabsolute humidity
问答题Practice 1 Heat loss by sweating depends on the fact that when a liquid evaporates, it absorbs an enormous quantity of heat from its surroundings. Therefore, when I am of sweat evaporate, a great deal of heat is absorbed from the surface of the body in contact with it. 1______ 2______ The first is the amount of movement of air surrounding the body. The second is the amount of water vapor in the air that surrounds the body. 3______ For this reason, sweat evaporates very rapidly on windy days, and the rate of heat loss by sweating is much more than on a still day. This accounts for the fact that hot still days are much less comfortable than hot windy days. In contrast, the sweat evaporates very rapidly on hot windy days, and cools the body quickly and effectively. 4______ When air is carrying the maximum amount of water vapor that it can hold, it is said to be 100% saturated with water vapor. The relative humidity of the air is said to be 100%. Under these conditions the air cannot carry any water, so no water can evaporate. When the relative humidity is high, therefore, sweat cannot evaporate. Instead, it forms large drops and runs off your skin without cooling you. 5______ It is obvious that under these conditions, evaporation will be much more rapid. Therefore, sweating will be much more effective as a method of losing heat from the body. On a hot dry day, sweat evaporates as soon as it is formed, and you feel reasonably cool even though the temperature of your environment is very high.[A] When the air is very dry and carries no water at all, the relative humidity is said to be 0%.[B] The second factor is the amount of water vapor in the air－the humidity.[C] Hot windy days are much more comfortable than hot still days.[D] This heat transfer occurs even if the environment is hotter than the body.[E] When air moves over the surface of water, the amount of evaporation is greatly increased.[F] You might expect the highest incidence of a heat stroke when the maximum temperature is 100 and humidity is 50%.[G] Two factors affect the rate of evaporation of sweat, and therefore the effectiveness of sweating as a method of cooling the body.
单选题Latent heat changes the （） of water.Aphysical stateBtemperatureCatmospheric pressureDsensible pressure
单选题Too much excess air is （）because the heat generated is being lost through the exhaust trunking instead of being made used of in heating the water to produce steam.Anot goodBgoodCbetterDthe best
单选题The heat used to change a liquid to a vapor is called （）.Alatent heat of fusionBlatent heat of vaporizationCspecific heat of vaporizationDlatent heat of the gas
单选题Early models of the flash-type evaporators used a separate shell-and-tube heat exchanger as the air ejector condenser.More recent models use a combined air ejector condenser with the（）Adistilling condenserBsalt water feed heaterCdistillate coolerDflash chamber
单选题The heat required to change a substance from a liquid to a gas without experiencing a temperature change is defined as the latent heat of （）.AfusionBvaporizationCsublimationDcondensation
单选题Relative humidity is the percentage of water vapor that is in the air as compared to the maximum amount it can hold at（）.Aa specific barometric pressureBa specific temperatureCa specific wind speedDany time
单选题The phraseheat recoveryrefers to a _____.Amethod of concealing the source of heatBspecial form of air-conditioningCsupplementary hot water systemDway of reclaiming and re-using heat
单选题In a shell-and-tube type hydraulic fluid cooler, the amount of heat transferred from the hydraulic fluid to the cooling water depends upon（）Athe temperature of the hydraulic fluidBthe flow rate of the hydraulic fluidCthe temperature of the cooling waterDall of the above
单选题The sensible heat of air is dependent upon the （）.Adry bulb temperatureBwet bulb temperatureCsaturation temperatureDwater vapor superheat
单选题The effective temperature of air is dependent upon（） Ⅰ.relative humidity Ⅱ.air velocityAⅠonlyBⅡonlyCBoth Ⅰand ⅡDNeitherⅠnor Ⅱ