The energy stored in coal ______.
The energy stored in coal ______.
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As there is less and less coal and oil, scientists are exploring new ways of making use of ____ energy, such as sunlight, wind and water for power and fuel.A. primary B. alternative C. instant D. unique
Besides climate change, developing countries like China need to deal with energy【21】and environmental issues: the development of sources of clean energy needs to be【22】line with their interests. Clean energy has been given greater prominence than ever before; it is seen as a new industrial【23】and【24】of economic growth for the new century. The time for clean energy has come.In China, clean energy is moving ahead at full speed. Take wind power as an example: by the end of last year, China had【25】wind power generating capacity of 12. 21GW, making China the largest wind power generator in Asia and fourth in the world. But according to the research, one-third of wind power capacity is running【26】due to an inability to get the power to the national【27】.India-like China—relies【28】on coal for its energy needs. This will only change if the funds and technology to develop clean energy, such as wind and nuclear power, are【29】. India will not choose clean energy【30】. Nuclear power is currently the most【31】of clean energy sources.【32】, if it is to be【33】on a large scale by developing nations, technological advances will be needed to make it competitive with coal.Compared【34】developed countries, developing countries have more【35】choices when it comes to energy structure. Promoting economic growth requires【36】energy—and coal, the cheapest and most【37】source of energy for many countries—is the【38】choice. Cheap coal means cheap electricity and a competitive economy. Rising electricity prices would cause public【39】and impact on standards of【40】.(21)A．scarceB．scareC．scarcityD．scary
The heat that is produced by burning garbage can be used to______.A. make electricityB. make energy sourceC. boil waterD. save coal
Coal mining industry in Britain prorides()of the energy consumed in the country, A 、one-thindB、one-fourthC、one-fthD、two-thinds
Before doing any work on a hydraulic system equipped with accumulators, you shouldA.drain the accumulators and purge with oxygenB.bleed off all stored energy from the accumulators completelyC.charge the accumulators to prevent system energy lossD.pump the hydraulic fluid into the accumulators to prevent fluid loss
As there is less and less coal and oil, scientists are exploring new ways of making use of _______ energy, such as sunlight, wind and water for power and fuel.A.primaryB.alternativeC.instantD.unique
共用题干Electromagnetic Energy1 White light seems to be a combination of all colors.The energy that comes from a source of light is not limited to the kind of energy you can see.Heat is given off by a flame or an electric light.On a cloudy day it is possible to get a sunburn even though you feel cool.Visible light and the kinds of energy that produce warmth and sunburn are examples of electromagnetic energy.2 The sun is 93 million miles from the earth.Yet we can use energy from the sun because electromagnetic energy travels through space.3 Many other kinds of energy are also types of electromagnetic energy.Radio,television,and radar signals travel from transmitters to receivers as low-energy electromagnetic waves.Infrared（红外线的）radiation is an electromagnetic wave.When it is absorbed by matter,heat is produced.Waves of infrared and visible light have more energy than waves of radio,television,or radar.Ultraviolet rays（紫外线）and X-rays are electromagnetic waves with even greater amounts of energy.Infrared radiation is used in cooking food and heating buildings. Sunlight and electric lights are part of our requirements for normal living.Ultraviolet radiation is useful in killing certain disease organisms.X-rays and gamma rays have so much energy that they travel through solid objects. They can be used to detect and treat cancer.X-rays are used in industry to find hidden cracks in metal,and in medicine to reveal broken bones.4 Usually we use electricity to generate electromagnetic energy.The source of most of our energy is the sun.Heat from the sun causes water to evaporate.When the water falls to the earth as rain,some of it is trapped behind dams and then used to operate electric generators.Other generators are powered by coal,but the energy stored in coal came from the sun,too.5 Until recently,the source of the tremendous amount of energy given off by the sun was a puzzle.If the sun depended on chemical reactions,it would have used up all its energy long ago.Experiments with electromagnetic radiation led to the theory that mass can be converted into energy.About forty years after the theory was proposed , nuclear energy was harnessed（利用）by man.Chemical energy comes from electron （电子）rearrangement.Nuclear energy comes from a change in the nucleus of an atom.Compared with chemical reactions,nuclear reactions release millions of times more energy per pound of fuel.We now believe that the sun's energy comes from the nuclear reactions in which hydrogen is changed into helium（氦）.6 Nuclear energy is beginning to compete with coal as an economical source of'power to generate electricity.It is also being used to operate engines in large ships.Scientists continue to seek new and better methods of obtaining and using energy.Infrared radiation can produce heat______. A:when it is absorbed by matterB:when it is cloudyC:because they can pass through solid objectsD:when the sunrays are fierce.E:when a change in the nucleus of an atom takes placeF:when electron rearrangement takes place
共用题干Electromagnetic Energy1 White light seems to be a combination of all colors.The energy that comes from a source of light is not limited to the kind of energy you can see.Heat is given off by a flame or an electric light.On a cloudy day it is possible to get a sunburn even though you feel cool.Visible light and the kinds of energy that produce warmth and sunburn are examples of electromagnetic energy.2 The sun is 93 million miles from the earth.Yet we can use energy from the sun because electromagnetic energy travels through space.3 Many other kinds of energy are also types of electromagnetic energy.Radio,television,and radar signals travel from transmitters to receivers as low-energy electromagnetic waves.Infrared（红外线的）radiation is an electromagnetic wave.When it is absorbed by matter,heat is produced.Waves of infrared and visible light have more energy than waves of radio,television,or radar.Ultraviolet rays（紫外线）and X-rays are electromagnetic waves with even greater amounts of energy.Infrared radiation is used in cooking food and heating buildings. Sunlight and electric lights are part of our requirements for normal living.Ultraviolet radiation is useful in killing certain disease organisms.X-rays and gamma rays have so much energy that they travel through solid objects. They can be used to detect and treat cancer.X-rays are used in industry to find hidden cracks in metal,and in medicine to reveal broken bones.4 Usually we use electricity to generate electromagnetic energy.The source of most of our energy is the sun.Heat from the sun causes water to evaporate.When the water falls to the earth as rain,some of it is trapped behind dams and then used to operate electric generators.Other generators are powered by coal,but the energy stored in coal came from the sun,too.5 Until recently,the source of the tremendous amount of energy given off by the sun was a puzzle.If the sun depended on chemical reactions,it would have used up all its energy long ago.Experiments with electromagnetic radiation led to the theory that mass can be converted into energy.About forty years after the theory was proposed , nuclear energy was harnessed（利用）by man.Chemical energy comes from electron （电子）rearrangement.Nuclear energy comes from a change in the nucleus of an atom.Compared with chemical reactions,nuclear reactions release millions of times more energy per pound of fuel.We now believe that the sun's energy comes from the nuclear reactions in which hydrogen is changed into helium（氦）.6 Nuclear energy is beginning to compete with coal as an economical source of'power to generate electricity.It is also being used to operate engines in large ships.Scientists continue to seek new and better methods of obtaining and using energy.Paragraph 4______A:Nuclear Reactions as the Lasting Source of the Sun's EnergyB:The Most Important Source of EnergyC:Types of Electromagnetic EnergyD:The Machines Used for Energy GenerationE:Seeking New Sources of EnergyF:The Use of Ultravio1et Radiation in Medicine
共用题干Electromagnetic Energy1 White light seems to be a combination of all colors.The energy that comes from a source of light is not limited to the kind of energy you can see.Heat is given off by a flame or an electric light.On a cloudy day it is possible to get a sunburn even though you feel cool.Visible light and the kinds of energy that produce warmth and sunburn are examples of electromagnetic energy.2 The sun is 93 million miles from the earth.Yet we can use energy from the sun because electromagnetic energy travels through space.3 Many other kinds of energy are also types of electromagnetic energy.Radio,television,and radar signals travel from transmitters to receivers as low-energy electromagnetic waves.Infrared（红外线的）radiation is an electromagnetic wave.When it is absorbed by matter,heat is produced.Waves of infrared and visible light have more energy than waves of radio,television,or radar.Ultraviolet rays（紫外线）and X-rays are electromagnetic waves with even greater amounts of energy.Infrared radiation is used in cooking food and heating buildings. Sunlight and electric lights are part of our requirements for normal living.Ultraviolet radiation is useful in killing certain disease organisms.X-rays and gamma rays have so much energy that they travel through solid objects. They can be used to detect and treat cancer.X-rays are used in industry to find hidden cracks in metal,and in medicine to reveal broken bones.4 Usually we use electricity to generate electromagnetic energy.The source of most of our energy is the sun.Heat from the sun causes water to evaporate.When the water falls to the earth as rain,some of it is trapped behind dams and then used to operate electric generators.Other generators are powered by coal,but the energy stored in coal came from the sun,too.5 Until recently,the source of the tremendous amount of energy given off by the sun was a puzzle.If the sun depended on chemical reactions,it would have used up all its energy long ago.Experiments with electromagnetic radiation led to the theory that mass can be converted into energy.About forty years after the theory was proposed , nuclear energy was harnessed（利用）by man.Chemical energy comes from electron （电子）rearrangement.Nuclear energy comes from a change in the nucleus of an atom.Compared with chemical reactions,nuclear reactions release millions of times more energy per pound of fuel.We now believe that the sun's energy comes from the nuclear reactions in which hydrogen is changed into helium（氦）.6 Nuclear energy is beginning to compete with coal as an economical source of'power to generate electricity.It is also being used to operate engines in large ships.Scientists continue to seek new and better methods of obtaining and using energy.X-rays and gamma rays can be used to detect and treat cancer______.A:when it is absorbed by matterB:when it is cloudyC:because they can pass through solid objectsD:when the sunrays are fierce.E:when a change in the nucleus of an atom takes placeF:when electron rearrangement takes place
共用题干Energy and Public LandsThe United States boasts substantial energy resources. Federal lands provide a good deal of US energy production,the US Department of the Interior manages federal energy leasing （租赁）both on land and on the offshore Outer Continental Shelf Production from these sources amounts to nearly 30 percent of total annual US energy production.In 2000,32 percent of US oil,35 percent of natural gas,and 37 percent of coal were pro-duced from federal lands,representing 20,000 producing oil and gas leases and 135 producing coal leases. Federal lands are also estimated to contain approximately 68 percent of all undis-covered US oil reserves and 74 percent of undiscovered natural gas.Revenues from federal oil,gas,and coal leasing provide significant returns to US taxpayers as well as State Government. In 1999,for example,$553 million in oil and gas revenues were paid to the US Treasury,and non-India coal leases accounted for over$304 million in revenues,of which 50 percent were paid to State governments. Public lands also play a critical role in energy delivery. Each year , federal land managers authorize（许可）rights of way for transmission lines , rail systems , pipe-lines,and other facilities related to energy production and use.Alternative energy production from federal lands falls behind conventional energy pro-duction , though the amount is still significant. For example , federal geothermal（地热）re-sources produce about 7. 5 billion kilowatt-hours（千瓦时）of electricity per year,47 percent of all electricity generated from US geothermal energy. There are 2,960 wind turbines on public lands in California alone,producing electricity for about 300,000 people. Federal hydropower （水电）facilities produce about 17 percent of all hydropower produced in the United States.Because of the growing US thirst for energy and increasing public unease with depend-ence on foreign off sources,pressure on public lands to meet US energy demand is becoming more intense. Public lands are available for energy development only after they have been evaluated through the land use planning process.If development of energy resources conflicts with management or use of other resources,development restrictions or impact moderation measures may be enforced,or mineral be banned altogether.Which of the following statements is true of public lands in the U. S.?A: Half of US energy is produced there.B: Most of coal was produced from there in 2000.C: Most energy resources are reserved there.D: The majority of undiscovered natural gas is stored there.
共用题干Thirst for OilWorldwide every day,we devour the energy equivalent of about 200 million barrels of oil. Most of the energy on Earth comes from the Sun. In fact enough energy from the Sun hits the planet's surface each minute to cover our needs for an entire year,we just need to find an efficient way to use it. So far the energy in oil has been cheaper and easier to get at. But as supplies dwindle,this will change,and we will need to cure our addiction to oil.Burning wood satisfied most energy needs until the steam-driven industrial revolution,when energy-dense coal became the fuel of choice. Coal is still used,mostly in power sta-tions,to cover one quarter of our energy needs,but its use has been declining since we star-ted pumping up oil. Coal is the least efficient,unhealthiest and most environmentally dama-ging fossil fuel,but could make a comeback,as supplies are still plentiful:its reserves are five times larger than oil's.Today petroleum,a mineral oil obtained from below the surface of the Earth and used to produce petrol,diesel oil and various other chemical substances,provides around 40% of the world's energy needs,mostly fuelling automobiles. The US consumes a quarter of all oil,and generates a similar proportion of greenhouse gas emissions.The majority of oil comes from the Middle East,which has half of known reserves. But other significant sources include Russia,North America,Norway,Venezuela and the North Sea. Alaska's Arctic National Wildlife Refuge could be a major new US source,to reduce reliance on foreign imports.Most experts predict we will exhaust easily accessible reserves within 50 years,though opinions and estimates vary. We could fast reach an energy crisis in the next few decades, when demand exceeds supply. As conventional reserves become more difficult to access,oth-ers such as oil shales and tar sands may be used instead. Petrol could also be obtained from coal.Since we started using fossil fuels,we have released 400 billion tonnes of carbon,and burning the entire reserves could eventually raise world temperatures by 13℃ .Among other horrors,this would result in the destruction of all rainforests and the melting of allArctic ice.Which of the following statements is NOT meant by the author,according to the second paragraph?A:Wood was the fuel of choice before coal.B: The use of coal is declining.C: Coal is the most environmentally unfriendly fuel next to oil.D: Coal reserves are plentiful and will be likely to become the major fuel of choice.
共用题干Energy and Public LandsThe United States boasts substantial energy resources. Federal lands provide a good deal of US energy production,the US Department of the Interior manages federal energy leasing （租赁）both on land and on the offshore Outer Continental Shelf Production from these sources amounts to nearly 30 percent of total annual US energy production.In 2000,32 percent of US oil,35 percent of natural gas,and 37 percent of coal were pro-duced from federal lands,representing 20,000 producing oil and gas leases and 135 producing coal leases. Federal lands are also estimated to contain approximately 68 percent of all undis-covered US oil reserves and 74 percent of undiscovered natural gas.Revenues from federal oil,gas,and coal leasing provide significant returns to US taxpayers as well as State Government. In 1999,for example,$553 million in oil and gas revenues were paid to the US Treasury,and non-India coal leases accounted for over$304 million in revenues,of which 50 percent were paid to State governments. Public lands also play a critical role in energy delivery. Each year , federal land managers authorize（许可）rights of way for transmission lines , rail systems , pipe-lines,and other facilities related to energy production and use.Alternative energy production from federal lands falls behind conventional energy pro-duction , though the amount is still significant. For example , federal geothermal（地热）re-sources produce about 7. 5 billion kilowatt-hours（千瓦时）of electricity per year,47 percent of all electricity generated from US geothermal energy. There are 2,960 wind turbines on public lands in California alone,producing electricity for about 300,000 people. Federal hydropower （水电）facilities produce about 17 percent of all hydropower produced in the United States.Because of the growing US thirst for energy and increasing public unease with depend-ence on foreign off sources,pressure on public lands to meet US energy demand is becoming more intense. Public lands are available for energy development only after they have been evaluated through the land use planning process.If development of energy resources conflicts with management or use of other resources,development restrictions or impact moderation measures may be enforced,or mineral be banned altogether.Geothermal resources,wind turbines,and hydropower facilities in Paragraph 4 are ci-ted as examples to illustrate that______.A: alternative energy production is no less than conventional energy productionB: they are the most typical conventional energy resources from public landsC: geothermal resources are more important than the other twoD: the amount of alternative energy production from public lands is huge
共用题干Electromagnetic Energy1 White light seems to be a combination of all colors.The energy that comes from a source of light isnot limited to the kind of energy you can see.Heat is given off by a flame or an electric light.On a cloudy day it is possible to get a sunburn even though you feel cool.Visible light and the kind of energy that produce warmth and sunburn are examples of electromagnetic energy.2 The sun is 93 million miles away from the earth.Yct we can use energy from die sun because elec-tromagnetic energy travels through space.3 Many other kinds of energy are also types of electromagnetic energy.Radio,television,and radar signais travel from transmitters to receivers as low-energy electromagnetic waves. Infrared（红外线的）radiation is an electromagnetic wave.When it is absorbed by matter,heat is produced.Wayes of infrared and visible light have more energy than waves of radio,television,or radar. Ultraviolet rays（紫外线）and X-rays are eleetro-magnetic waves with even greater amounts of energy.Infrared radiation is used in cooking food and heating buildings.Sunlight and electric lights are part of our requirements for normal living. Ultraviolet radiation is useful in killing certain disease organisms.X-rays and gamma rays have so much energy that they travel right through solid objects.They can be used to detect and treat cancer。 X-rays are used in industry to find hiddencracks in metal,and in medicine to reveal broken bones.4 Usually we use electricity to generate electromagnetic energy.The source of most of our energy is the sun.Heat from the sun causes water to evaporate.When the water falls to the earth as rain,some of it is trapped behind dams and then used to operate electric generators,Other generators are powered by coal,but the energy stored in coal came from the sun,too.5 Until recently,the source of the tremendous amount of energy given off by the sun was a puzzle.If the sun depended on chemical reactions,it would have used up all its energy long ago.Experiments with electromagnetic radiation led to the theory that mass can be converted into energy．入bout forty years after the theory was proposed , nuclear energy was harnessed（利用）by man. Chemical energy comes from electron （电子）rearrangement. Nuclear energy comes from a change in the nucleus of an atom. Compared with chemi- cal reactions,nuclear reactions release millions of times more energy per pound of fuel.We now believe that the sun's energy comes from the nuclear reactions in which hydrogen is changed into helium（氦）.6 Nuclear energy is beginning to compete with coal as an economical source of power to generate elec- tricity.It is also being used to operate engines in large ships.Scientists continue to seek new and bettermethods of obtaining and using energy.We can use energy from the sun because_______________.A:electromagnetic energyB:electromagnetic energy travels through spaceC:came from the sunD:when a change in the nucleus of an atom takes placeE:whlen the sunrays are fierce F:chemical energy is generated
共用题干Green Energy1.Green energy is energy that is produced in a manner that has, less of a negative impact to the environment than energy sources like fossil fuels,which are often produced with harmful side effects."Greener" types of energy that often come to mind are solar,wind,geothermal and hydro energy.There are several more,even including nuclear energy,that is sometimes considered a green energy source because of its lower waste output relative to energy sources such as coal or oil.2.The goal of green energy is generally to create power with as little pollution as possible produced as a by-product. Every form of energy collection will result in some pollution,but those that are green are known to cause less than those that are not. Most people who advocate greener sources of energy claim that the result of worldwide use of green energy will result in the ability to preserve the planet for a longer time.Greenhouse gases,a by-product of traditional sources of energy such as fossil fuels are thought to be causing global warming,or the process of the Earth heating up at an accelerated pace.3.It is not completely necessary for green energy sources to come from places like solar or wind fields,which are examples of green"power plants".A green energy source can be a building that is designed in a way that it keeps itself cool in the daytime and heated in the night through its architectural design rather than having an air-conditioning or a heating system. The conservation of energy through architectural（建筑学的）design becomes, itself, a green energy source. Similarly, many sources of green energy can come directly from the area in which the energy is needed rather than from an outside source.4.One of the goals of green energy technology is to take existing fossil fuel energy technology and clean it up so it is produced more cleanly. One such case is that of clean coal technology,where scientists are trying to find ways to extract energy from coal and other fossil fuels without all of the harmful side effects.The success of such these types of green energy depend upon the ability to extract harmful by-products from fossil fuels while not only being energy efficient,but by being cost efficient as well.Greenhouse gases are thought to be causing______.A:global warmingB:carbon emissionC:lower waste outputD:a green energy sourceE:fossil fuels F: clean fuels
共用题干Green Energy1.Green energy is energy that is produced in a manner that has, less of a negative impact to the environment than energy sources like fossil fuels,which are often produced with harmful side effects."Greener" types of energy that often come to mind are solar,wind,geothermal and hydro energy.There are several more,even including nuclear energy,that is sometimes considered a green energy source because of its lower waste output relative to energy sources such as coal or oil.2.The goal of green energy is generally to create power with as little pollution as possible produced as a by-product. Every form of energy collection will result in some pollution,but those that are green are known to cause less than those that are not. Most people who advocate greener sources of energy claim that the result of worldwide use of green energy will result in the ability to preserve the planet for a longer time.Greenhouse gases,a by-product of traditional sources of energy such as fossil fuels are thought to be causing global warming,or the process of the Earth heating up at an accelerated pace.3.It is not completely necessary for green energy sources to come from places like solar or wind fields,which are examples of green"power plants".A green energy source can be a building that is designed in a way that it keeps itself cool in the daytime and heated in the night through its architectural design rather than having an air-conditioning or a heating system. The conservation of energy through architectural（建筑学的）design becomes, itself, a green energy source. Similarly, many sources of green energy can come directly from the area in which the energy is needed rather than from an outside source.4.One of the goals of green energy technology is to take existing fossil fuel energy technology and clean it up so it is produced more cleanly. One such case is that of clean coal technology,where scientists are trying to find ways to extract energy from coal and other fossil fuels without all of the harmful side effects.The success of such these types of green energy depend upon the ability to extract harmful by-products from fossil fuels while not only being energy efficient,but by being cost efficient as well.Paragraph 3______A:Why Do We Develop Green Energy?B:What Is the Goal of Green Energy?C:What Is the Weakness of Green Energy?D:What Is a Green Energy?E:How Much Does the Green Energy Cost Every Year?F: How Many Kinds of Green Energy We Can Take Use of?
共用题干Electromagnetic Energy1 White light seems to be a combination of all colors.The energy that comes from a source of light isnot limited to the kind of energy you can see.Heat is given off by a flame or an electric light.On a cloudy day it is possible to get a sunburn even though you feel cool.Visible light and the kind of energy that produce warmth and sunburn are examples of electromagnetic energy.2 The sun is 93 million miles away from the earth.Yct we can use energy from die sun because elec-tromagnetic energy travels through space.3 Many other kinds of energy are also types of electromagnetic energy.Radio,television,and radar signais travel from transmitters to receivers as low-energy electromagnetic waves. Infrared（红外线的）radiation is an electromagnetic wave.When it is absorbed by matter,heat is produced.Wayes of infrared and visible light have more energy than waves of radio,television,or radar. Ultraviolet rays（紫外线）and X-rays are eleetro-magnetic waves with even greater amounts of energy.Infrared radiation is used in cooking food and heating buildings.Sunlight and electric lights are part of our requirements for normal living. Ultraviolet radiation is useful in killing certain disease organisms.X-rays and gamma rays have so much energy that they travel right through solid objects.They can be used to detect and treat cancer。 X-rays are used in industry to find hiddencracks in metal,and in medicine to reveal broken bones.4 Usually we use electricity to generate electromagnetic energy.The source of most of our energy is the sun.Heat from the sun causes water to evaporate.When the water falls to the earth as rain,some of it is trapped behind dams and then used to operate electric generators,Other generators are powered by coal,but the energy stored in coal came from the sun,too.5 Until recently,the source of the tremendous amount of energy given off by the sun was a puzzle.If the sun depended on chemical reactions,it would have used up all its energy long ago.Experiments with electromagnetic radiation led to the theory that mass can be converted into energy．入bout forty years after the theory was proposed , nuclear energy was harnessed（利用）by man. Chemical energy comes from electron （电子）rearrangement. Nuclear energy comes from a change in the nucleus of an atom. Compared with chemi- cal reactions,nuclear reactions release millions of times more energy per pound of fuel.We now believe that the sun's energy comes from the nuclear reactions in which hydrogen is changed into helium（氦）.6 Nuclear energy is beginning to compete with coal as an economical source of power to generate elec- tricity.It is also being used to operate engines in large ships.Scientists continue to seek new and bettermethods of obtaining and using energy.Paragraph 4__________________A:Nuclear Reactions as the Lasting Source of the Sun's EnergyB:The Most Imoprtant Source of EnergyC:Types of Eleetromagnetie EnergyD:X-rays Are Used to Detect and Treat CancerE:Seeking New Sourees of EnergyF:Nuclear Energy Is Beginning to Compete With Coal
共用题干Electromagnetic Energy1 White light seems to be a combination of all colors.The energy that comes from a source of light isnot limited to the kind of energy you can see.Heat is given off by a flame or an electric light.On a cloudy day it is possible to get a sunburn even though you feel cool.Visible light and the kind of energy that produce warmth and sunburn are examples of electromagnetic energy.2 The sun is 93 million miles away from the earth.Yct we can use energy from die sun because elec-tromagnetic energy travels through space.3 Many other kinds of energy are also types of electromagnetic energy.Radio,television,and radar signais travel from transmitters to receivers as low-energy electromagnetic waves. Infrared（红外线的）radiation is an electromagnetic wave.When it is absorbed by matter,heat is produced.Wayes of infrared and visible light have more energy than waves of radio,television,or radar. Ultraviolet rays（紫外线）and X-rays are eleetro-magnetic waves with even greater amounts of energy.Infrared radiation is used in cooking food and heating buildings.Sunlight and electric lights are part of our requirements for normal living. Ultraviolet radiation is useful in killing certain disease organisms.X-rays and gamma rays have so much energy that they travel right through solid objects.They can be used to detect and treat cancer。 X-rays are used in industry to find hiddencracks in metal,and in medicine to reveal broken bones.4 Usually we use electricity to generate electromagnetic energy.The source of most of our energy is the sun.Heat from the sun causes water to evaporate.When the water falls to the earth as rain,some of it is trapped behind dams and then used to operate electric generators,Other generators are powered by coal,but the energy stored in coal came from the sun,too.5 Until recently,the source of the tremendous amount of energy given off by the sun was a puzzle.If the sun depended on chemical reactions,it would have used up all its energy long ago.Experiments with electromagnetic radiation led to the theory that mass can be converted into energy．入bout forty years after the theory was proposed , nuclear energy was harnessed（利用）by man. Chemical energy comes from electron （电子）rearrangement. Nuclear energy comes from a change in the nucleus of an atom. Compared with chemi- cal reactions,nuclear reactions release millions of times more energy per pound of fuel.We now believe that the sun's energy comes from the nuclear reactions in which hydrogen is changed into helium（氦）.6 Nuclear energy is beginning to compete with coal as an economical source of power to generate elec- tricity.It is also being used to operate engines in large ships.Scientists continue to seek new and bettermethods of obtaining and using energy.The energy stored in coal_______________.A:electromagnetic energyB:electromagnetic energy travels through spaceC:came from the sunD:when a change in the nucleus of an atom takes placeE:whlen the sunrays are fierce F:chemical energy is generated
共用题干Electromagnetic Energy1 White light seems to be a combination of all colors.The energy that comes from a source of light isnot limited to the kind of energy you can see.Heat is given off by a flame or an electric light.On a cloudy day it is possible to get a sunburn even though you feel cool.Visible light and the kind of energy that produce warmth and sunburn are examples of electromagnetic energy.2 The sun is 93 million miles away from the earth.Yct we can use energy from die sun because elec-tromagnetic energy travels through space.3 Many other kinds of energy are also types of electromagnetic energy.Radio,television,and radar signais travel from transmitters to receivers as low-energy electromagnetic waves. Infrared（红外线的）radiation is an electromagnetic wave.When it is absorbed by matter,heat is produced.Wayes of infrared and visible light have more energy than waves of radio,television,or radar. Ultraviolet rays（紫外线）and X-rays are eleetro-magnetic waves with even greater amounts of energy.Infrared radiation is used in cooking food and heating buildings.Sunlight and electric lights are part of our requirements for normal living. Ultraviolet radiation is useful in killing certain disease organisms.X-rays and gamma rays have so much energy that they travel right through solid objects.They can be used to detect and treat cancer。 X-rays are used in industry to find hiddencracks in metal,and in medicine to reveal broken bones.4 Usually we use electricity to generate electromagnetic energy.The source of most of our energy is the sun.Heat from the sun causes water to evaporate.When the water falls to the earth as rain,some of it is trapped behind dams and then used to operate electric generators,Other generators are powered by coal,but the energy stored in coal came from the sun,too.5 Until recently,the source of the tremendous amount of energy given off by the sun was a puzzle.If the sun depended on chemical reactions,it would have used up all its energy long ago.Experiments with electromagnetic radiation led to the theory that mass can be converted into energy．入bout forty years after the theory was proposed , nuclear energy was harnessed（利用）by man. Chemical energy comes from electron （电子）rearrangement. Nuclear energy comes from a change in the nucleus of an atom. Compared with chemi- cal reactions,nuclear reactions release millions of times more energy per pound of fuel.We now believe that the sun's energy comes from the nuclear reactions in which hydrogen is changed into helium（氦）.6 Nuclear energy is beginning to compete with coal as an economical source of power to generate elec- tricity.It is also being used to operate engines in large ships.Scientists continue to seek new and bettermethods of obtaining and using energy.When electron rearrangement takes place_______________.A:electromagnetic energyB:electromagnetic energy travels through spaceC:came from the sunD:when a change in the nucleus of an atom takes placeE:whlen the sunrays are fierce F:chemical energy is generated
共用题干Green Energy1.Green energy is energy that is produced in a manner that has, less of a negative impact to the environment than energy sources like fossil fuels,which are often produced with harmful side effects."Greener" types of energy that often come to mind are solar,wind,geothermal and hydro energy.There are several more,even including nuclear energy,that is sometimes considered a green energy source because of its lower waste output relative to energy sources such as coal or oil.2.The goal of green energy is generally to create power with as little pollution as possible produced as a by-product. Every form of energy collection will result in some pollution,but those that are green are known to cause less than those that are not. Most people who advocate greener sources of energy claim that the result of worldwide use of green energy will result in the ability to preserve the planet for a longer time.Greenhouse gases,a by-product of traditional sources of energy such as fossil fuels are thought to be causing global warming,or the process of the Earth heating up at an accelerated pace.3.It is not completely necessary for green energy sources to come from places like solar or wind fields,which are examples of green"power plants".A green energy source can be a building that is designed in a way that it keeps itself cool in the daytime and heated in the night through its architectural design rather than having an air-conditioning or a heating system. The conservation of energy through architectural（建筑学的）design becomes, itself, a green energy source. Similarly, many sources of green energy can come directly from the area in which the energy is needed rather than from an outside source.4.One of the goals of green energy technology is to take existing fossil fuel energy technology and clean it up so it is produced more cleanly. One such case is that of clean coal technology,where scientists are trying to find ways to extract energy from coal and other fossil fuels without all of the harmful side effects.The success of such these types of green energy depend upon the ability to extract harmful by-products from fossil fuels while not only being energy efficient,but by being cost efficient as well.The success of green energy depend upon the ability to extract harmful by-products from______.A:global warmingB:carbon emissionC:lower waste outputD:a green energy sourceE:fossil fuels F: clean fuels
共用题干Green Energy1.Green energy is energy that is produced in a manner that has, less of a negative impact to the environment than energy sources like fossil fuels,which are often produced with harmful side effects."Greener" types of energy that often come to mind are solar,wind,geothermal and hydro energy.There are several more,even including nuclear energy,that is sometimes considered a green energy source because of its lower waste output relative to energy sources such as coal or oil.2.The goal of green energy is generally to create power with as little pollution as possible produced as a by-product. Every form of energy collection will result in some pollution,but those that are green are known to cause less than those that are not. Most people who advocate greener sources of energy claim that the result of worldwide use of green energy will result in the ability to preserve the planet for a longer time.Greenhouse gases,a by-product of traditional sources of energy such as fossil fuels are thought to be causing global warming,or the process of the Earth heating up at an accelerated pace.3.It is not completely necessary for green energy sources to come from places like solar or wind fields,which are examples of green"power plants".A green energy source can be a building that is designed in a way that it keeps itself cool in the daytime and heated in the night through its architectural design rather than having an air-conditioning or a heating system. The conservation of energy through architectural（建筑学的）design becomes, itself, a green energy source. Similarly, many sources of green energy can come directly from the area in which the energy is needed rather than from an outside source.4.One of the goals of green energy technology is to take existing fossil fuel energy technology and clean it up so it is produced more cleanly. One such case is that of clean coal technology,where scientists are trying to find ways to extract energy from coal and other fossil fuels without all of the harmful side effects.The success of such these types of green energy depend upon the ability to extract harmful by-products from fossil fuels while not only being energy efficient,but by being cost efficient as well.Nuclear energy is sometimes considered a green energy source because of its______.A:global warmingB:carbon emissionC:lower waste outputD:a green energy sourceE:fossil fuels F: clean fuels
共用题干第一篇Energy and Public LandsThe United States boasts substantial energy resources?Federal lands provide。good deal of US energy production,the US Department of the Interior manages federal energy leasing（租赁）,both on land and on the offshore Outer Continental Shelf. Production from these sources amounts to nearly 30 percent of total annual US energy production.In 2000,32 percent of US oil,35 percent of natural ga9,and 37 percent Of coal were produced from federal lands,representing 20,000 producing oil and gas leases and 135 producing coal leases.Federal lands are also estimated to contain approximately 68 percent of all undiscovered US oil reserves and 74 percent of undiscovered natural gas.Revenues from federal oil,gas,and coal leasing provide significant returns to US taxpayers as well as State government,In 1999,for example,$553 million in oil and gas revenues were paid to the US Treasury,and non-Indian coal leases accounted for over $304 million in revenues, of which 50 percent were paid to State governments,Public lands also play a critical role in energy delivery.Each year,federal land managers authorize rights of way for transmission lines,rail systems,pipelines,and other facilities related to energy production and use.Alternative energy production from federal lands falls behind conventional energy production,though the amount is still significant. For example , federal geothermal (地热）resources produce about 7. 5 billion kilowatt-hours（千瓦时）of electricity per year , 47 percent of all electricity generated from US geothermal energy.There are 2,960 wind turbines on public lands in California alone,producing electricity for about 300 ,000 people. Federal hydropower（水电）facilities produce about 17 percent of all hydropower produced in the United States.Because of the growing US thirst for energy and increasing public unease with dependence on foreign oil sources,pressure on public lands to meet US energy demnand is becoming more intense.Public lands areavailable for energy development oniy after they have been evaivated through the land use planning process. If development of energy resources conflicts with management or use of other resources,development restric- lions or impact moderation measures may be enforced,or mineral production may he banned altogether.Public lands can be used for energy development when ________.A:energy development restrictions are effectiveB:federal land managers grant perrmssionsC:they go through the land use planning processD:there is enough federal budget
Coal mining industry in Britain provides( )of the energy consumed in the country. A.one-third B.one-fourth C.one-fifth D.two-thirds
As some countries attempt to shift away from natural gas or petroleum energy systems toward coal-based systems, the need for coal slurry(煤泥) will increase in these countries,（）transport mode will be the first choice for transfer this kind of product.A、Water carriageB、Pipeline transportC、Rail transportD、Surface transport
单选题According to information given in the passage, which of the following statements presents the most accurate comparison of an average ton of coal from Wyoming with an average ton of coal from the Appalachian range in West Virginia?AThe former is cheaper and has higher sulfur content than the latter.BThe latter is found closer to the surface and contains more sulfur than the former.CThe former can help coal-burning power plants meet limits on sulfur dioxide emissions and costs more than the latter.DThe latter generates more energy per pound of coal than the former.EThe former is found closer to the surface than the latter and helps coal-burnning power plants meet limits on sulfur dioxide emissions.
多选题Because free hydrogen does not exist in nature, it cannot be ______ a primary energy source, as coal or oil can.Aborne in mindBtaken into accountCconcerned withDconsideredEremarked uponFthought of as
单选题Before doing any work on a hydraulic system equipped with accumulators, you should（）Adrain the accumulators and purge with oxygenBbleed off all stored energy from the accumulators completelyCcharge the accumulators to prevent system energy lossDpump the hydraulic fluid into the accumulators to prevent fluid loss