网友您好， 请在下方输入框内输入要搜索的题目：
题目内容
（请给出正确答案）
单选题
Hot air can hold（）.
A
less moisture than cold air
B
more moisture than cold air
C
the same amount of moisture as cold air
D
moisture independent of air temperature
参考答案
参考解析
解析：
暂无解析
更多 “单选题Hot air can hold（）.A less moisture than cold airB more moisture than cold airC the same amount of moisture as cold airD moisture independent of air temperature” 相关考题
考题
Man has always wanted to fly.Even as long as eight hundred years ago, an Englishman had tried.He made a (1)of wings from chicken feathers and fixed them to his shoulders.Then he jumped om a tall building.As you can imagine, he did not fly very far.(2) he fell to the ground and broke several bones.The first real attempt at flying took place in France in 1783.The two Mongolian brothers knew that hot air rose.If they couldfill a large balloon(3)hot air, they thought it would rise into the air and fly.They were right.They made a very large hot air balloon of cloth and paper.It measured ten meters it diameter.They filled it with hot air and the balloon got two hundred meters into the air.It fell into earth about three kilometers away.At the next attempt, they (4) passengers use a bal loon to rise into the air and fly.We do not know what the passengers fell about the trip as they were a cock, a duck, and a sheep But we (5) know that the trip lasted eight minutes and the animals landed safely.(完型填空)A.InsteadB.PairC.DoD.ArrangedE.With
考题
Hygroscopic cargoes should be ventilated when ______.A.going from a warm to a cold climateB.the dew point of the outside air is greater than the dew point of the air in the holdC.the dew point of the air in the hold is very lowD.the outside dew point is 16°C and the cargo temperature is 12°C
考题
Sweat damage will occur in a cargo hold containing machinery parts when ______.A.the outside air is colder than the cargo．B.the air temperature of the hold is higher than the outside air temperature．C.the dew point of the hold is higher than the temperature of the cargo．D.the dew point of the outside air is lower than the temperature of the cargo
考题
Should the steel be loaded in conditions where the ambient temperature is lower than might be encountered later on in the voyage，______．A.the hold should be ventilatedB.the hold should not be ventilatedC.the hold should be half-ventilatedD.hot air should be introduced into the hold
考题
The moisture equilibrium chart can be used to determine the ______．A.Absolute moisture content of the air surrounding a hygroscopic cargo when moisture equilibrium existsB.Dew point temperature that the air surrounding a hygroscopic commodity will have when in moisture equilibrium with that commodityC.Enthalpy of the air surrounding a hydroscopic cargo which is in moisture equilibrium with the cargoD.Temperature at which moisture equilibrium will occur in a cargo hold containing a hygroscopic cargo
考题
共用题干
Rockets in the SkyIf someone asked you,"What color is the sky?"I expect that you would answer,"Blue."I am afraid that you would be wrong.The sky has no color.When we see blue,we are looking at blue sunlight.The sunlight is shining on little bits of dust in the air.We know that there is air all around the world.We could not breathe without air.Airplanes could not fly without air.They need air to lift their wings.Airplanes cannot fly very high because as they go higher the air gets thinner.If we go far enough away from the earth,we find there is no air.What is the sky?The sky is space.In this space there is nothing except the sun,the moon and all the stars. Scientists have always wanted to know more about the other worlds in the space.They have looked at them through telescopes and in this way they have found out a great deal.The moon is about 384 ,000 kilometers away from the earth.An airplane cann't fly to the moon but there is a thing that can fly even when there is no air. This is rocket.I am sure that you are asking,"How does a rocket fly?"If you want to know,get a balloon and then blow it up until it is quite big.Do not tie up the neck of the balloon.Let go!The balloon will fly off through the air very quickly.The air inside the balloon tries to get out.It rushes out through the neck of the balloon and this pushes the balloon through the air.It does not need wings like an airplane.This is how a rocket works.It is not made of rubber（橡胶）like a balloon,of course.It is made of metal. The metal must not be heavy but it must be very strong.There is gas inside the rocket which is made very hot. When it rushes out of the end of the rocket,the rocket is pushed up into the air.Rockets can fly far out into space.Rockets with men inside them have already reached the moon.Several rockets,without men inside them,have been sent to other worlds much farther away.One day rockets may be able to go anywhere in the space.A rocket is pushed up into the air when.A:hot gas rushes out of its headB:it is powered by gasC:hot gas rushes out of its bottomD:hot gas rushes out of its neck
考题
Air Bus’ world-renowned hot-section engineering______the needs of industrial gas turbine customers.A.replies
B.answers
C.frees
D.addresses
考题
The No.3 air cycle pack temperature indication is______hot.A.being read
B.to read
C.reading
D.read
考题
Which of the following is a reason why Bob, a technician, should install case fans in the front of acomputer case?（）A、It forces hot air out of the PCB、The fan is easier to remove and cleanC、It forces cooler air into the power supply quicklyD、It forces cooler air across the motherboard
考题
单选题Hot gas defrosting uses the hot gas from （） to defrost the evaporator.A
starting air bottlesB
diesel enginesC
boilersD
refrigeration compressors
考题
单选题—Can we please get a new air conditioner for our bedroom? — ______ —Can’t you see that it’s not working right?A
Do you have to repair it?B
It is not very hot in this season.C
I also think we should buy a new one.D
What’s wrong with the one we have now?
考题
单选题A hot air start pipe indicates that there is （）.A
inefficient coolingB
a leaking air start valveC
a clogged drain valveD
a leaking air bottle
考题
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.
考题
单选题Sweat damage will occur in a cargo hold containing machinery parts when（）.A
the outside air is colder than the cargoB
the air temperature of the hold is higher than the outside air temperatureC
the dew point of the hold is higher than the temperature of the cargoD
the dew point of the outside air is lower than the temperature of the cargo
考题
单选题In reference to air conditioning, when air attains the maximum amount of moisture it can hold at a specific temperature, it is said to be （）.A
superheatedB
saturatedC
condensedD
convected
考题
单选题The moisture equilibrium chart can be used to determine the（）.A
Absolute moisture content of the air surrounding a hygroscopic cargo when moisture equilibrium existsB
Dew point temperature that the air surrounding a hygroscopic commodity will have when in moisture equilibrium with that commodityC
Enthalpy of the air surrounding a hydroscopic cargo which is in moisture equilibrium with the cargoD
Temperature at which moisture equilibrium will occur in a cargo hold containing a hygroscopic cargo
考题
单选题Hygroscopic cargoes should be ventilated when（）.A
going from a warm to a coldB
the dew point of the outside air is greater than the dew point of the air in the holdC
the dew point of the air in the hold is very lowD
the outside dew point is 16°C and the cargo temperature is 12°C
考题
单选题The amount of moisture in a given sample of air, when compared with the amount of moisture the air could hold if totally saturated at the existing temperature of the sample, is called （）.A
absolute humidityB
specific humidityC
effective humidityD
relative humidity
考题
单选题When comparing the air with 50% of relative humidity with the air with 100% of relative humidity, which one will hold more water?（）A
the formerB
the latterC
not for sureD
same each other
考题
单选题Directional intake ports in diesel engines are used to （）.A
reduce air charge turbulenceB
induce air swirlC
deflect hot combustion gas away from the valvesD
oppose the effects of piston induced squish
考题
单选题Which of the following is a reason why Bob, a technician, should install case fans in the front of acomputer case?（）A
It forces hot air out of the PCB
The fan is easier to remove and cleanC
It forces cooler air into the power supply quicklyD
It forces cooler air across the motherboard
考题
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（）.A
a specific barometric pressureB
a specific temperatureC
a specific wind speedD
any time
考题
单选题In extreme weather conditions, either hot or cold, control of the air conditioning plant presents （） difficulties.A
fewB
littleC
a littleD
less
考题
单选题Hot air can hold（）.A
less moisture than cold airB
more moisture than cold airC
the same amount of moisture as cold airD
moisture independent of air temperature
考题
单选题Hygroscopic cargoes should be ventilated when（）.A
going from a warm to a cold climateB
the dew point of the outside air is greater than the dew point of the air in the holdC
the dew point of the air in the hold is very lowD
the outside dew point is 16°C and the cargo temperature is 12°C
考题
单选题Hygroscopic cargoes should be ventilated when（）.A
going from a warm to a cold climateB
the dew point of the outside air is greater than the dew point of the air in the holdC
the dew point of the air in the hold is very lowD
the outside dew point is 16℃ and the cargo temperature is 12℃
考题
单选题When the dew point of the outside air is lower than or equal to the dew point of the air in the cargo hold，you should（）.A
secure all ventilationB
shut down the exhaust blowersC
shut down the intake blowersD
ventilate the cargo holds
热门标签
最新试卷