首页
外语
计算机
考研
公务员
职业资格
财经
工程
司法
医学
专升本
自考
实用职业技能
登录
外语
Answer questions 71~80 by referring to the following games. Note:Answer each question by choosing A, B, C or D. Some choices
Answer questions 71~80 by referring to the following games. Note:Answer each question by choosing A, B, C or D. Some choices
admin
2011-01-02
33
问题
Answer questions 71~80 by referring to the following games.
Note:Answer each question by choosing A, B, C or D. Some choices maybe required more than once.
A=Hydro power B=Nuclear power C=Solar power D=Wind power
Which power(power’s)…
A
Hydro power
Introduction
We have used running water as an energy source for thousands of years, mainly to grind com.
The first house in the world to be lit by hydroelectricity was Cragside House, in Northumberland, England, in 1878. In 1882 on the Fox River, in the USA, hydroelectricity produced enough power to light two paper mills and a house.
Nowadays there are many hydro-electric power stations, providing around 20% of the world’s electricity. The name comes from“hydro”, the Greek word for water.
How it works
A dam is built to trap water, usually in a valley where there is an existing lake.
Water is allowed to flow through tunnels in the dam, to turn turbines and thus drive generators.
Advantages
Once the dam is built, the energy is virtually free.
No waste or pollution produced.
Much more reliable than wind, solar or wave power.
Water can be stored above the dam ready to cope with peaks in demand.
Hydro-electric power stations can increase to full power very quickly, unlike other power stations.
Disadvantages
The dams are very expensive to build.
Building a large dam will flood a very large area upstream, causing problems for animals that used to live there.
Finding a suitable site can be difficult--the impact on residents and the environment may be unacceptable.
Water quality and quantity downstream can be affected, which can have an impact on plant life.
Is it renewable?
Hydro-electric power is renewable.
The Sun provides the water by evaporation from the sea, and will keep on doing so.
B
Nuclear power
Introduction
Nuclear power is generated using Uranium, which is a metal mined in various parts of the world.
The first large-scale nuclear power station opened at Calder Hall in Cambria, England, in 1956.
Some military ships and submarines have nuclear power plants for engines.
How it works
Nuclear power stations work in pretty much the same way as fossil fuel-burning stations, except that a“chain reaction”inside a nuclear reactor makes the heat instead.
The reactor uses Uranium rods as fuel, and the heat is generated by nuclear fission. Neutrons smash into the nucleus of the uranium atoms, which split roughly in half and release energy in the form of heat.
Carbon dioxide gas is pumped through the reactor to take the heat away, and the hot gas then heats water to make steam.
Advantages
Nuclear power costs about the same as coal, so it’s not expensive to make.
Does not produce smoke or carbon dioxide, so it does not contribute to the greenhouse effect.
Produces huge amounts of energy from small amounts of fuel.
Produces small amounts of waste.
Disadvantages
Although not much waste is produced, it is very, very dangerous.
It must be sealed up and buried for many years to allow the radioactivity to die away.
Nuclear power is reliable, but a lot of money has to be spent on safety.
Is it renewable?
Nuclear energy from Uranium is not renewable.
Once we’ve dug up all the Earth’s uranium and used it. there isn’t any more.
C
Solar power
Introduction
We’ve used the Sun for drying clothes and food for thousands of years. but only recently have we been able to use it for generating power.
The Sun is 150 million kilometers away, and amazingly powerful.
Just the tiny fraction of the Sun’s energy that hits the Earth(around a hundredth of a millionth of a percent) is enough to meet all our power needs many times over.
How it works
There are three main ways that we use the Sun’s energy:
Solar Cells(really called“photovoltaic”or“photoelectric”cells)that convert light directly into electricity.
In a sunny climate, you can get enough power to run a 100W light bulb from just one square meter of solar panel.
This was originally developed in order to provide electricity for satellites, but these days many of us own calculators powered by solar cells.
Solar water heating, where heat from the Sun is used to heat water in glass panels on your roof.
This means you don’t need to use so much gas or electricity to heat your water at home.
Solar Furnaces use a huge array of mirrors to concentrate the Sun’s energy into a small space and produce very high temperatures.
Advantages
Solar energy is free-it needs no fuel and produces no waste or pollution.
In sunny countries, solar power can be used where there is no easy way to get electricity to a remote place.
Handy for low-power uses such as solar powered garden lights and battery chargers.
Disadvantages
Doesn’t work at night.
Very expensive to build solar power stations.
Solar cells cost a great deal compared to the amount of electricity they’ll produce in their lifetime.
Can be unreliable unless you’re in a very sunny climate.
Is it renewable?
Solar power is renewable. The Sun will keep On shining anyway, so it makes sense to use it.
D
Wind power
Introduction
We’ve used the wind as an energy source for a long time. The Babylonians and Chinese were using wind power to pump water for irrigating crops 4,000 years ago, and sailing boats were around long before that.
Wind power was used in the Middle Ages, in Europe, to grind corn. which is where the term“windmill”comes from.
How it works
The Sun heats our atmosphere unevenly, so some patches become warmer than others.
These warm patches of air rise, other air blows in to replace them—and we feel a wind blowing.
We can use the energy in the wind by building a tall tower, with a large propeller on the top. The wind blows the propeller round, which turns a generator to produce electricity.
The more towers, the more wind, and the larger the propellers, the more electricity we can make.
Advantages
Wind is free, wind farms need no fuel.
Produces no waste or greenhouse gases.
The land beneath can usually still be used for farming.
Wind farms Can be tourist attractions.
A good method of supplying energy to remote areas.
Disadvantages
The wind is not always predictable—some days have no wind.
Suitable areas for wind farms are often near the coast, where land is expensive.
Can kill birds—migrating flocks tend to like strong winds.
Can affect television reception if you live nearby.
Is it renewable?
Wind power is renewable. Winds will keep on blowing; it makes sense to use them.
______produces small amounts of waste?
选项
A、
B、
C、
D、
答案
B
解析
由B中的内容“Produces small amounts of waste. ”可知答案为B。
转载请注明原文地址:https://kaotiyun.com/show/dpHd777K
本试题收录于:
公共英语五级笔试题库公共英语(PETS)分类
0
公共英语五级笔试
公共英语(PETS)
相关试题推荐
WhichofthefollowingstatementsaboutHenryFordisNOTtrue?Amagnetoisatechnicaltermfor
WhichofthefollowingstatementsaboutFlowersandYeoistrue?Theword"affect"inParagraph6couldbebestreplacedby
Itisestimatedthatthereare______peoplesufferingfromobesityintheworld.Fromthelastparagraphwemayinferthatone
YouthEmancipationinSpainTheSpanishGovernmentissoworriedaboutthenumberofyoungadultsstilllivingwiththeirpa
Regularvisitsfromasocialworkercanbeofimmensevaluetooldpeoplelivingalone.
HowaTerribleBattleHelpedtoChangeEuropeNinetyyearsagoonasunnymorninginNorthernFrance,somethinghappenedtha
TheScienceofPersuasionIfleadershipconsistsofgettingthingsdonethroughothers,thenpersuasionisoneoftheleader
BeautyBeautyhasalwaysbeenregardedassomethingpraiseworthy.Almosteveryonethinksattractivepeoplearehappierandh
DNAFingerprintingDNAisthegeneticmaterialfoundwithinthecellnucleiofalllivingthings.Inmammalsthestrandsof
A.humanisbornwithacertainpersonalityB.howthepersonalityandbehaviorareformedC.willexperienceintellectualdevel
随机试题
背景:北方某房屋建筑工程,地上20层,地下2层,建筑面积22000m2。桩基础,冻土层厚800mm,地上剪力墙结构。质量目标:合格。工期450日历天。施工单位中标后成立了项目部,并于2009年11月15日进场。施工过程中发生了如下事件:事件一:项目部编
无论是西文字符还是中文字符,在计算机一律用()编码来表示。
最易发生肋骨骨折的是
积液一级检查内容包括()
车间管理人员的工资不属于直接工资,因而不能计入产品成本,而应计入期间费用。()
从纵向看,我国教育制度结构包括()。(2016.广西)
一件产品要经过三道工序,每道工序的合格率分别为99.98%,99.95%,99.93%。该产品的合格率是多少?()
某单位有甲、乙两个部门,若从甲部门调动7个人到乙部门,则乙部门的人数比甲部门的人数多2倍,若从乙部门调动5个人到甲部门,则甲、乙两部门人数相等,问甲部门有多少人?()
设若Ax=0的基础解系由2个线性无关的解向量构成,
某计算机系统输入/输出采用双缓冲工作方式,其工作过程如下图所示,假设磁盘块与缓冲区大小相同,每个盘块读入缓冲区的时间T为10μs,缓冲区送用户区的时间M为6μs,系统对每个磁盘块数据的处理时间C为2μs。若用户需要将大小为10个磁盘块的:Doc1文件逐块从
最新回复
(
0
)