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单选题
What is the role the T5 plays?
A
Throttles up and down to counteract the buffeting from air molecules.
B
Feels the subtle variations in Earth’s tug.
C
Helps accelerometers surive the launch
D
Provides powerful force to counteract the drag on Goce.
参考答案
参考解析
解析：
题目问的是：T5扮演什么角色？倒数第14段提到“British engine is designed to throttle up and down to counteract this disturbance.”可知通过上下节流来抵消干扰，A项与原文一致。故选A。
题目问的是：T5扮演什么角色？倒数第14段提到“British engine is designed to throttle up and down to counteract this disturbance.”可知通过上下节流来抵消干扰，A项与原文一致。故选A。
更多 “单选题What is the role the T5 plays?A Throttles up and down to counteract the buffeting from air molecules.B Feels the subtle variations in Earth’s tug.C Helps accelerometers surive the launchD Provides powerful force to counteract the drag on Goce.” 相关考题
考题
（B）The surprising experiment I am about to describe proves that air is all around you and that it proves down upon you. Air pressure is a wonderful force. When you swim underwater, you can feel water push down your body. The air all around you does the same. However, your body is so used to it that you do not notice this. The pressure is caused by a layer of air called the atmosphere. This layer surrounds the Earth, extending to about five kilometers above the Earth’s surface.The following experiment is an easy one that you can do at home. But make sure that you are supervised, because you will need to use matches. Now foe the experiment！What you need?A hard-boiled egg without the shell?A bottle with a neck slightly smaller than the egg?A piece of paper?A matchMetheod1） Check that the paper will sit firmly on the neck of the bottle.2） Tear the paper into strips and put the strips into the bottle.3） Light the paper by dropping a burning match into the bottle.4） Quickly sit the egg on the neck of the bottle.ResultAstonishingly, the egg will be sucked into the bottle. Your friends will be amazed when you show them the experiment. But be careful when you handle matches.Why it happenedAs the paper burns, it needs oxygen and uses up the oxygen （air） in the bottle. The egg acts as a seal in the neck of the bottle, so no more air can get inside. This reduces the air pressure inside the bottle. The air pressure must equalize, so more air from outside must enter the bottle. The outside air pressure against the egg and then the egg is pushed into the bottle! The proves that air is all around and that it is pressing down on it.60. Why is there the need to take care when you are doing the experiment?A. The bottle could break.B. You need to light the paper with a match.C. The egg needs to be shelled.D. The egg has to be perfectly placed on the neck of the bottle.
考题
The experiment is carried cut to prove ______.A. water pushes on your body when you swim underwater.B. the earth is surrounded by a layer of air called the atmosphere.C. the pressure of air around us has a powerful force.D. the air pressure is not equalized around us.
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"The trouble with being the Prime Minister's sister is it puts your life into perspective." is from the movie().A、LoveA、ctuallyB、PocahontasC、TarzanD、Air Force One
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What can be concluded from the passage?A. A fuelling ambition plays a leading role in one’s success.B. A responsible adviser is more important than the knowledge of writing.C. As to the growth of a genius, I.Q. doesn’t matter, but just his/her efforts.D. What really matters is what you do rather than who you are.
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A mean sun is used as the reference for solar time for three reasons. Which reason is NOT a cause for use of a mean sun?A.The motion of the apparent sun is along the eclipticB.Measurement of time is along the celestial equatorC.The speed of the Earth's revolution is not constantD.There are variations in the Earth's rotational speed
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What is the function of an air receiver in the compressed air system on a ship?A.Condenses moistureB.Provides overpressure protectionC.Purifies the airD.Acts as an accumulator
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考题
Geothermal(地热)Energy
1 Since heat naturally moves from hotter regions to cooler ones, the heat from the earth's center flows outwards towards the surface. In this way, it transfers to the next layer of rock. If the temperature is high enough, some of this rock melts and forms magma(岩浆). The magma ascends in its turn towards the earth's surface. It often remains well below the earth's surface, creating vast areas of hot rock. In such regions, there are deep cracks, which allow rainwater to descend underground. Some of the heated rainwater travels back up to the earth's surface where it will appear as a hot spring. However, if this ascending hot water reaches a layer of impermeable(不可渗透的)rock, it remains trapped, forming a geothermal reservoir. If geothermal reservoirs are close enough to the surface, they can be reached by drilling wells. Hot water and steam shoot up the wells naturally, and can be used to produce electricity in geothermal power plants.
2.A few geothermal power plants depend on dry-stem reservoirs which produce steam but little or no water. In these cases, the steam is piped up directly to provide the power to spin a turbine generator. The first geothermal power plant, constructed at Lardarello in Italy, was of this type, and is still producing electricity today.
3.Most currently operating geothermal power plants are either "flash" steam plants or binary(双重的)plants. Flash plants produce mainly hot water ranging in temperature from 300° to 700°Fahrenheit. This water is passed through one or two separators where released from the pressure of the underground reservoir, it "flashes" or boils into steam Again, the force of this steam provides the energy to spin the turbine and produce electricity. The geothermal water and steam are then reinjected directly back down into the earth to maintain the volume and pressure of the reservoir. Gradually they will be reheated and can then be used again.
4.A reservoir with temperatures below 300° Fahrenheit is not hot enough to flash steam but it can still be used to generate electricity in binary fluid. The steam from this is used to power the turbines. As in the flash steam plant, the geothermal water is recycled back into the reservoir.
文章(23~30)
Paragraph1_____A.Dry steam plants
B.Binary plants
C.Origin of geothermal energy
D.Generation of electricity
E.Flash steam plants
F.Recyclable water and steam
考题
共用题干
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考题
共用题干
第一篇A Sunshade（遮阳伞）for the PlanetEven with the best will in the world,reducing our carbon emissions is not going to prevent global warming. It has become clear that even if we take the most strong measures to control emissions, the uncertainties in our climate models still leave open the possibility of extreme warming and rises in sea level. At the same time,resistance by governments and special interest groups makes it quite possible that the actions suggested by climate scientists might not be implemented soon enough.Fortunately,if the worst comes to the worst,scientists still have a few tricks up their sleeves. For the most part they have strongly resisted discussing these options for fear of inviting a sense of complacency that might thwart efforts to tackle the root of the problem. Until now,that is a growing number of researchers are taking a fresh look at large-scale"geoengineering"projects that might be used to counteract global warming."I use the analogy of methadone,"says Stephen Schneider,a climate researcher at Stanford University in California who was among the first to draw attention to global warming."If you have a heroin addict,the correct treatment is hospitalization,and a long rehab. But if they absolutely refuse,methadone is better than heroin."Basically the idea is to apply"sunscreen"to the whole planet. One astronomer has come up with a radical plan to cool Earth:launch trillions of feather-light discs into space,where they would form a vast cloud that would block the sun's rays.It's controversial,but recent studies suggest there are ways to deflect just enough of the sunlight reaching the Earth's surface to counteract the warming produced by the greenhouse effect. Global climate models show that blocking just 1.8 percent of the incident energy in the sun's rays would cancel out the warming effects produced by a doubling of greenhouse gases in the atmosphere.That could be crucial,because even the most severe emissions control measures being proposed would leave us with a doubling of carbon dioxide by the end of this century,and that would last for at least a century more.What is NOT true of the effectiveness of"sunscreen",according to the last paragraph?A:It deflects sunlight reaching the Earth to counteract the warming.B:It blocks the incident energy in the sun's rays.C:It is a controversial method.D:It decreases greenhouse gases in the atmosphere.
考题
单选题To counteract these undesirable effects cylinder oils usually contain additives formulated to impart a high degree of （） and detergency.A
salinityB
alkalinityC
acidD
sanitary
考题
单选题What is the role the T5 plays?A
Throttles up and down to counteract the buffeting from air molecules.B
Feels the subtle variations in Earth’s tug.C
Helps accelerometers surive the launchD
Provides powerful force to counteract the drag on Goce.
考题
单选题The third paragraph plays what role in the passage?A
It summarizes all the points expressed in the first two paragraphs.B
It raises new arguments that expand on those previously expressed.C
It suggests a possible area for useful research in the future.D
It rejects the arguments expressed in the first paragraph.E
It provides concrete evidence against arguments expressed in the second paragraph.
考题
单选题What has the United Nations made up its mind to do from the passage?A
Set an Earth Protecting DayB
Protect and love the earthC
Hold an international meetingD
Find out what is making the pollution
考题
单选题The connecting rod is fitted between the crosshead and the crankshaftI t transmits the firing force, and together with the crankshaft converts the （）motion to a （）motion.A
rotary；reciprocatingB
up and down；fore and aftC
fore and aft；up and downD
up and down；rotary
考题
单选题The four-stroke cycle begins with the piston （）.A
coming up from the BDCB
coming up from the TDCC
coming down from the BDCD
coming down from the TDC
考题
单选题A vacuum is initially established in the first and second stages of a low pressure evaporator by the use of （）A
vacuum drag from the auxiliary condensate systemB
individual vacuum pumpsC
a single non-condensing air ejectorD
a two stage air ejector
考题
单选题When rigging a bosun’s chair，a tail block or lizard is used to（）.A
guide the bosun's chair down a stay when applying a protective coatingB
run paint or tools up to a sailor in a chair with a heaving lineC
keep a bosun's chair from swinging with the ship's motionD
reeve the gantline through
考题
单选题A mean sun is used as the reference for solar time for three reasons. Which reason is NOT a cause for use of a mean sun?（）A
The motion of the apparent sun is along the eclipticB
Measurement of time is along the celestial equatorC
The speed of the Earth's revolution is not constantD
There are variations in the Earth's rotational speed
考题
单选题These students’ determination to face up to difficulties plays a crucial role in their success.A
live up toB
stand up toC
go up toD
add up to
考题
单选题The author concludes that only shared myths can help Americans ______.A
to bring about the uniformity of their cultureB
to regain their consensus about a common experienceC
to stay away from negative feelings in their lifeD
to counteract the effects of consensus about society
考题
单选题The force resulting from the earth’s rotation that causes winds to deflect to the right in the Northern Hemisphere and to the left in the Southern Hemisphere is called（）.A
pressure gradientB
Coriolis effectC
aurora borealisD
ballistic deflection
考题
单选题What is the basic principle of the magnetic compass?（）A
Magnetic materials of the same polarity repel each other and those of opposite polarity attractB
The Earth's magnetic lines of force are parallel to the surface of the EarthC
Magnetic meridians connect points of equal magnetic variationD
The compass needle(s) will，when properly compensated，lie parallel to the isogonic lines of the Earth
考题
单选题The connecting rob is fitted between the crosshead and the crankshaftIt transmits the firing force, and together with the crankshaft convert the （） motion to a （） motion.A
rotary；reciprocatingB
up and down；fore and aftC
fore and aft；up and downD
up and down；rotary
考题
单选题The magnetic compass magnets are acted on by the horizontal component of the Earth’s total magnetic force. This magnetic force is GREATEST at the（）.A
north magnetic poleB
south magnetic poleC
magnetic prime vertical meridianD
magnetic equator
考题
单选题The purpose of an air compressor unloading device is to （）A
drain water from the air receiverB
drain water from the cylindersC
delay the compression process until the motor is up to speedD
check pump alignment
考题
单选题The transition of the Earth’s magnetic field is possibly caused by _____.A
the flows of melted iron inside the EarthB
the periodical movement of the EarthC
the mechanical energy of the solar systemD
the force coming from outer space
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