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[单选题]

A solar day is the length of time ______ the earth to revolve once around the sun． A．takes B．takes

A.A.takes

B.B.takes it

C.C.it takes

D.D.he take

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发布时间：2020-07-19

更多“A solar day is the length of time ______ the earth to revolve once around the sun． A．takes B．takes”相关的问题

第1题

Millions of people around the world cook their food over a smoky fire every day. It is

often difficult to find wood for the fire. People who do not have wood must spend large amounts of money on cooking fuel. However, there is a much easier way to cook food using energy from the sun. Solar cookers, or ovens, have been used for centuries.

Solar ovens consist of a system of reflectors and a cooking pot. The rest is up to your imagination! Once you have collected or bought your solar oven, you can use it to prepare hot meals in the backyard, at a campground or wherever your heart desires.

Of all the inventions that could benefit humankind, a reliable solar cooker remains one of the most necessary. Countless people across the developing world still cook their food by burning wood or even cow dung, causing breathing problems and severe pollution in some regions.

The searching for a practical solar cooker has gone on for decades and produced dozens of models. But none of them have caught on importantly for use in the developing world because they can’t store heat. Without the ability to store heat, a cooker cannot be used, for example, on cloudy days.

But now a group based at the Norwegian University of Science and Technology (NTNU) is reporting a discovery in solar cookers. They say it will lead to the production of practical solar cookers within a year and a half and it can store enough heat during a sunny day to work for an entire additional day, even if it is cloudy.

1.People who do not have wood must spend small amounts of money on cooking fuel.()

2.There is a much easier way to cook food using energy from the sun.()

3.Solar cookers, or ovens, have not been used for centuries.()

4.Solar ovens consist of a system of reflectors and a cooking pot.()

5.Without the ability to store heat, a cooker can be used, for example, on cloudy days.()

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第2题

Although the practice of the old Roman religion disappeared many centuries ago, some tra

ces of the Roman gods are still present in our daily vocabulary. The names of the Roman sun god, Sol, and the moon goddess, Luna, are used frequently in our language The word solar describes anything pertaining to the sun, and lunar anything pertaining to the moon. For example, the sun and the planets circling it are called the solar system. The period of time in which the earth circles the sun once is a solar year. The moon takes one lunar month to circle the earth. A lunar year of twelve lunar months is eleven days shorter than a solar year. In some cases our language shows how these heavenly bodies affect us directly. A room or place for sunbathing is often called a solarium. We get our word parasol from the Italian word meaning " a guard against the sun." For many centuries it was believed that the moon affected people who were mentally ill. For this reason persons who were mentally ill were often referred to as lunatics.

1).The word lunatic originally meant___.

A、twelve lunar months

B、the home of the moon goddess

C、a person on whom the moon had a bad effect

D、a guard against the moon

2).Implied but not stated______.

A、A solar year lasts about 354 days

B、Sol was the Roman sun god

C、Our calendar is based on the movements of the moon

D、Mental illness really has nothing to do with the moon

3).In comparison with the solar year, the lunar year is__.

A、twice as long

B、the same length

C、shorter

D、a few days longer

4).A parasol is used to __.

A、measure solar time

B、protect us from the sun rays

C、protect us from the gods

D、view the sun during the day

5).The best title for this selection is:___.

A、The Gods of Rome

B、The Rhythm of the Universe

C、Ancient Beliefs

D、Gods in Our Words

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第3题

If the sun has enough【C1】______to warm and light the whole earth, it must have enough powe

r to do other things,【C2】______. Can we use the sun's【C3】______energy to supply electricity, or at least to perform. the function which electricity or other types of power usually perform？ The answer is【C4】______.

For example, people have for many years been using the【C5】______heat of the sun to cook by solar【C6】______which have been built with several incurred【C7】______reflecting the sun and focusing the heat on the cooking element. This【C8】______can be used like a gas or electric stove; it is more expensive to make but it doesn't need any【C9】______and so costs【C10】______to use. Another【C11】______of using solar energy is in house heating.

The【C12】______of energy we use most is electricity, and every day more is【C13】______. But electricity has to be made too, and to make it huge quantities of fuel is required -- oil, coal, gas and nowadays even uranium.

The question which【C14】______everyone today is: how long will these fuels【C15】______？ Nobody knows it for sure,【C16】______most experts think it will soon be difficult to obtain sufficient electricity from these sources. It is possible that the sun can make a(n)【C17】______here, too.

Solar power has already been used to produce【C18】______heat. In Southern France a solar furnace has been built,【C19】______temperatures reach more than 3 000 centigrade. This furnace is not only used for experiment【C20】______, but could be used to produce steam for a power station.

【C1】

A．power

B．time

C．heat

D．temperature

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第4题

根据以下材料，回答题Better Solar Energy Systems: More Heat， More LightSolar photovoltaic th

根据以下材料，回答题

Better Solar Energy Systems: More Heat， More Light

Solar photovoltaic thermal energy systems， or PVTs， generate both heat and electricity， but__________ （51） now they haven"t been very good at the heat-generating part compared to a stand-alone solar thermal collector. That"s because they operate at low temperatures to cool crystalline silicon solar cells，__________ （52） lets the silicon generate more electricity but isn"t a very efficient way to gather heat.

That"s a problem of economics. Good solar hot-water systems can harvest much more energy than a solar-electric system at a substantially lower__________（53）. And it"s also a space problem: photovoltaic cells can__________ （54） up all the space on the roof， leaving little room for thermal applications.

In a pair of studies， Joshua Pearce， an associate professor of materials science and engineering，has devised a__________ （55） in the form. of a better PVT made with a different kind of silicon.

His research collaborators are Kunal Girotra from Thin Silicon in California and Michael Pathak and Stephen Harrison from Queen"s University， Canada.

Most solar panels are made with crystalline silicon， but you can also make solar cells out of amorphous silicon， commonly known__________ （56） thin-film silicon. They don"t create as much electricity， but they are lighter， flexible， and cheaper. And， because they__________ （57） much less silicon， they have a greener footprint. __________ （58）， thin-film silicon solar cells are vulnerable to some bad-news physics in the form. of the Staebler-Wronski effect.

"That means that their efficiency drops when you __________（59） them to light——pretty much the worst possible effect for a solar cell，" Pearce explains， which is one of the__________ （60） thin-film solar panels make up only a small fraction of the market.

However， Pearce and his team found a __________（61） to engineer around the Staebler-Wronski effect by incorporating thin-film silicon in a new __________（62） of PVT. You don"t have to cool down thin-film silicon to make it work. In fact， Pearce"s group discovered that by heating it to solar-thermal operating temperatures， near the boiling__________ （63） of water， they could make thicker cells that largely __________（64） the Staebler-Wronski effect. When they applied the thin-film silicon directly to a solar thermal energy collector， they also found that by baking the cell once a day， they__________ （65） the solar cell"s electrical efficiency by over 10 percent.

回答（51）题查看材料

A.until

B.unless

C.when

D.if

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第5题

When night falls in remote parts of Africa and the Indian subcontinent, hundreds of millio

ns of people without access to electricity turn to candles or flammable and polluting kerosene lamps for illumination.

Slowly through small loans for solar powered devices, microfinance is bringing light to these rural regions where a lack of electricity has stymied economic development, literacy rates and health. A woman sews clothes on a sewing machine driven by solar energy in Ahmedabad/ Photo credit: Amit Dave/ Reuters

“Earlier, they could not do much once the sun set. Now, the sun is used differently. They have increased their productivity, improved their health and socio-economic status,” said Pinal Shah from SEWA Bank, a micro -lending institution.

Vegetable seller Ramiben Waghri took out a loan to buy a solar lantern which she uses to light up her stall at night. The lantern costs between $66-$112, about a week？ s income for Waghri.

“The vegetables look better by this light, and it？ s cheaper than kerosene and doesn？ t smell,” said Waghri, who estimates she makes about 300 rupees ($6) more each evening with her lantern.

“If we can use the sun to save some money, why not？”

In India, solar power projects, often funded by micro credit institutions, are helping the country reduce carbon emissions and achieve its goal to double the contribution of renewable energy to 6%, or 25,000 megawatts, within the next four years.

Off-grid applications such as solar cookers and lanterns, which can provide several hours of light at night after being charged by the sun during the day, will help cut dependence on fossil fuels and reduce the fourth biggest emitter？ s carbon footprint, said Pradeep Dadhich, a senior fellow at energy research institute TERI.

“They are reaching people who otherwise have limited or no access to electricity, and depend on kerosene, diesel or firewood for their energy needs,” he said.“The applications not only satisfy these needs, they also improve the quality of life and reduce the carbon footprint.”

SEWA or Self Employed Women？ s Association, is among a growing number of microfinance institutions in India focused on providing affordable renewable energy sources to poor people, who otherwise would have had to stand for hours to buy kerosene for lamps, or trudge miles to collect firewood for cooking.

SKS Microfinance, India？ s largest MFI, offers solar lamps to its 5 million customers, while Grameen Surya Bijlee (Rural Solar Electricity) Foundation helps fund lamps and home and street lighting systems for villagers in India, Nepal and Bangladesh.

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第6题

We accept 60 day’s L/C ____ this deal.

A.with

B.for

C.in

D.at

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第7题

There are millions of stars and planets in space.What's the difference between sta

rs and planets？ Stars can give out heat and light, but planets cannot.

The sun is one of the stars.Some planets are balls of rock and some are balls of gas.We live on the planet earth.The earth spins around once every day to give us day and night.The earth goes around the sun once every year to give us different seasons.

There are eight planets moving around the sun.We call the family of the sun and its planets the solar system.Mercury is the nearest to the sun, so it is very hot.It is the smallest planet.Venus is very bright and hot.It is the nearest to the earth.Mars is covered with orange-red desi and rocks, so it looks like a red star in the sky.It has seasons like the earth.Jupiter has more than 16 moons (卫星)and it is the biggest and heaviest planet.Saturn has more than 22 moons.The other planets, such as Uranus and Neptune, are all very far from the sun and very cold.We need a telescope (望远镜) to see them.

(1)The sun can give us().

A.heat and water

B.heat and light

C.light and air

D.rock and water

(2)The Chinese meaning of "spin around" is().

A.飞行

B.行驶

C.环绕

D.旋转

(3)The earth goes around()once every year to give us different seasons.

A.the moon