Imagine what you could do with a machine that could make things disappear.

For inspiration, you could read some books. In the books of J.R.R. Tolkein, Bilbo Baggins finds a ring that can make him disappear. Of course, there’s also poor Harry Potter, who used his invisibility cloak (隱形斗篷) to hide from danger.

Now that you’ve got some ideas, it’s time for the hard part: building the cloak. To do that, you have to give up science fiction and turn to real science. An invisibility cloak has to cheat anything or anyone who might be watching. In order to understand how something can be seen, it’s important to understand how we see.

Human beings can only see objects that reflect (反射) light waves. These waves enter the eye and are then processed by the brain. However, if an object doesn’t reflect light, then the waves don’t enter the eye, and the brain doesn’t process. So building an invisibility cloak is building something that doesn’t reflect light.

Cummer was part of a team of scientists from Duke University, including David Smith and David Schurig, who built the world’s first version (版本) of an invisibility cloak. They had been inspired by the work of a British physicist, John Pendry. He in May said that an invisibility cloak was possible and Pendry was not the only one thinking about a disappearing act. At the same time, a Scottish physicist, UIf Leonhardt published a paper on building invisibility equipment.

“It wasn’t easy,” says Cummer. “As often happens in science and research, it didn’t work very well the first time. That first cloak didn’t work like Harry Potter’s --- the scientists didn’t actually see anything disappear. So the research is still under way. ”

1.The first two paragraphs serve as a (n) ________.

A. introduction B. explanation

C. comment D. summary

2.Cummer and other scientists got the idea of building an invisibility cloak from _________.

A. the film Harry Potter

B. the work of a British physicist

C. a paper published by a Scottish physicist

D. the book of J.R.R. Tolkein

3. From the text we learn that the research on an invisibility cloak __________.

A. was led by Pendry

B. was very successful

C. was used in most popular movies

D. is still in progress

4.What can be the best title for the text?

A. The Science of Disappearing

B. The Hardest Part of Building a Cloak

C. The Invention of an Invisibility Cloak

D. Turn Science Fiction into Real Science

練習(xí)冊系列答案
相關(guān)習(xí)題

科目：高中英語 來源：2014-2015學(xué)年重慶市高三上學(xué)期第一次月考英語試卷（解析版） 題型：單項填空

_____ his great courage, the boy was left alone in a dark room, no lighted candle_____ it up．

A． Considered；lighted

B． Considering；lighting

C． Having considered；lighted

D． To consider；lighting

查看答案和解析>>

科目：高中英語 來源：2016屆江蘇啟東中學(xué)高三上學(xué)期第一次月考英語試卷（解析版） 題型：單項填空

—Why? Where is the key to the sound lab?

—Dear me! You _____ it in the taxi！

A. have never left B. haven’t left

C. never left D. didn’t leave

查看答案和解析>>

科目：高中英語 來源：2015-2016學(xué)年黑龍江大慶鐵人中學(xué)高二上期中英語試卷（解析版） 題型：語法填空

閱讀下面材料， 在標有1-10的空格處填入適當?shù)膬?nèi)容（不多于3個單詞）或括號內(nèi)單詞的正確形式。

One Sunday morning in August I went to a local music festival. I left it early because I had an appointment 1. (late) that day. My friends walked me to the bus stop and waited with me2. he bus arrived. I got on the bus and found a seat near the back, and then I noticed a man 3. (seat) at the front. He4. (pretend) that a tiger toy was real and giving it a voice. He must be 5. (mental) disabled. Behind him were other people to 6. he was trying to talk, but after some minutes they walked away and sat near me, looking annoyed.

I didn't want7. (laugh) at for talking to him but I didn't like leaving him8. his owneither. After a while I rose from my seat and walked to the front of the bus. I sat next to the man and introduced myself. We had9. amazing conversation. He got off the bus before me and I felt very happy the rest of the way home.

I'm glad I made the choice. It made 10. of us feel good.

查看答案和解析>>

科目：高中英語 來源：2015-2016學(xué)年黑龍江大慶鐵人中學(xué)高二上期中英語試卷（解析版） 題型：單項填空

The school requested that all the students ____ school uniform on weekdays in school.

A. wear B. wore C. wears D. have worn

查看答案和解析>>

科目：高中英語 來源：2015-2016學(xué)年甘肅天水第一中學(xué)高一上第二段考英語試卷（解析版） 題型：閱讀理解

Today, roller skating is easy and fun. But a long time ago, it wasn’t easy at all. Before 1750, the idea of skating didn’t exist. That changed because of a man named Joseph Merlin. Merlin’s work was making musical instruments. In his spare time he liked to play the violin. Joseph Merlin was a man of ideas and dreams. People called him a dreamer.

One day Merlin received an invitation to attend a fancy dress ball. He was very pleased and a little excited. As the day of the party came near, Merlin began to think how to make a grand entrance at the party. He had an idea. He thought he would get a lot of attention if he could skate into the room.

Merlin tried different ways to make himself roll. Finally, he decided to put two wheels under each shoe. These were the first roller skates. Merlin was very proud of his invention and dreamed of arriving at the party on wheels while playing the violin.

On the night of the party Merlin rolled into the room playing his violin. Everyone was greatly surprised to see him. There was just one problem. Merlin had no way to stop his roller skates. He rolled on and on. Suddenly, he ran into a huge mirror that was hanging on the wall. Down fell the mirror, breaking to pieces. Nobody forgot Merlin’s grand entrance for a long time!

1.The text is mainly about __________.

A. a strange man

B. an unusual party

C. how roller skating began

D. how people enjoyed themselves in the 18th century

2.People thought Merlin was a dreamer because he __________.

A. was full of imagination

B. was a gifted musician

C. invented the roller skates

D. often gave others surprises

3.Merlin put wheels under his shoes in order to __________.

A. show his skill in walking on wheels

B. arrive at the party sooner

C. test his invention

D. impress the party guests

查看答案和解析>>

科目：高中英語 來源：2014-2015學(xué)年陜西西安臨潼區(qū)華清中學(xué)高三一模考英語試卷（解析版） 題型：閱讀理解

Homework and stress are rarely reduced inside the classroom．Meanwhile，outside the classroom，the pressure is on to find scholarships for college．

According to Braintrack，a higher education database with worldwide reach，more than 3 billion US dollars (18 billion yuan) in private scholarships are awarded to college students annually．Average awards range from $2,000 to $3,000．

The scholarship application process is similar to the college application process: forms to be completed，test scores and transcripts to be sent，essays to be written and often interviews to be prepared for．

A few great places to start looking for scholarships are: www．fastweb．com，www．finaid．org and www．collegexpress．com．Check out the annual scholarship guidebooks Scholarships，Grants & Prizes by Peterson’s and the Ultimate Scholarship Book: Billions of Dollars in Scholarships，Grants and Prizes by Gen Tanabe and Kelly Tanabe．

Be selective．Thoroughly research the qualifications required by each of the scholarships．Don’t waste your time applying for those that are need based if you can’t produce the appropriate documents．

Research past recipients (接受者)．Check out the websites of the organizations sponsoring the scholarships．Many post the biographies of past recipients．You don’t need to have cured cancer，but if you don’t think your résumé (履歷) measures up to the past winners’，you might be better served by moving onto the next scholarship on your list．Prepare for the interview．

You’ll want to dazzle them with your personality，but above all you’ll want to be prepared．Find someone you trust to conduct a similar interview with you – someone who will be honest with you and provide valuable suggestions．

Let your personality shine through in your essays．The essays are the best way for students to share who they are，where they’ve come from，what they’ve overcome and so on．Tell your story in an interesting and persuasive way．And if you do have an interview，send a thank you note afterward．

By Lee Bierer

1.What is the author’s main purpose in writing the article？

A．To explain where to find scholarships for US colleges．

B．To inform readers of the scholarship application process．

C．To introduce some typical scholarships offered by US colleges．

D．To give tips on applying for US college scholarships．

2.If you want to learn about past recipients of a scholarship，you can use ______．

A．www．collegexpress．com

B．the annual scholarship guidebooks published by Peterson’s

C．the websites of the organizations sponsoring the scholarships

D．The Ultimate Scholarship Book: Billions of Dollars in Scholarships，Grants and Prizes

3.The underlined word “dazzle” in Paragraph 7 is closest in meaning to ___．

A．influence B．impress C．guide D．present

4.To increase your chance of winning a scholarship，you are advised to ____．

A．a(chǎn)pply for as many scholarships as you can

B．tell an interesting story in your essay

C．do a similar interview to help you prepare for the real one

D．have a talk with past recipients and try to talk like they do

查看答案和解析>>

科目：高中英語 來源：2014-2015學(xué)年山東省高三第一次診斷性考試英語試卷（解析版） 題型：閱讀理解

Today we’ll talk about reading．When we read a text，our eyes move across a page in short，quick movements．We recognize words usually when our eyes still fixate（停留，凝視）．Each time they fixate，we see a group of words．This is known as the recognition span or the visual span（視幅）．The length of time for which the eyes stop varies from person to person．It also varies within any parson according to his purpose in reading and his familiarity with the text．In addition，it can be affected by such factors as lighting and tiredness．

Unfortunately，in the past，many reading improvement courses have concentrated too much on how our eyes move across the page．As a result of this misleading emphasis（強調(diào)）on the purely visual aspects of reading，many exercises have been designed to train the eyes to see more words at one fixation．For example，in some exercises，words are flashed on to a screen for a tenth of a second．One of the exercises has required students to fix their eyes on some central point，taking in the words on either side．Such word patterns are often formed in the shape of pyramids（金字塔），so the reader takes in more and more words at each successive（連續(xù)的）fixation．All these exercises are very clever，but it' s one thing to improve a person’s ability to see words and quite another thing to improve his ability to read a text efficiently．Reading requires the ability to understand the relationship between words．Consequently，for these reasons，many experts have now begun to question the usefulness of eye training，especially since any approach which trains a person to read isolated（孤立的）words and phrases would seem unlikely to help him in reading a continuous text．

1.The time of the recognition span can be affected by the following factors except _______．

A． 1ighting and tiredness

B． the length of a group of words

C． one’s purpose in reading

D． one’s familiarity with the text

2.The author may believe that reading ______________．

A． requires a reader to take in more words at each fixation

B． requires a reader to see words more quickly

C． demands a deeply-participating mind

D． demands more eyes than mind

3.What does the author mean by the underlined sentence in the second paragraph?

A． The ability to see words is not needed for an efficient reading．

B． The reading exercises mentioned are useless for reading．

C． The reading exercises mentioned can’t help improve reading．

D． The reading exercises mentioned have done a great job so far．

4.Which of the following is NOT true? _______________．

A． The visual span is a word or a group of words we see each time

B． Many experts began to question the efficiency of eye training

C． The emphasis on the purely visual aspects is misleading

D． The eye training will help readers in reading a continuous text

5.The tune of the author in writing this text is _________________．

A． critical B． neutral

C． supportive D． optimistic

查看答案和解析>>

科目：高中英語 來源：2016屆河南省百校聯(lián)盟高三11月教育教學(xué)質(zhì)量檢測A卷英語試卷（解析版） 題型：閱讀理解

The World Health Organization warns that millions of people are dying every year from indoor air pollution. The WHO finds that poor cooking, heating and lighting technologies are killing millions of people each year.

Indoor air pollution results from the use of dangerous fuels and cook-stoves in the home. To help fight the problem, the WHO announced, new guidelines aimed at reducing household pollutants.

WHO officials say nearly three billion people are unable to use clean fuels and technologies for cooking? heating and lighting. And they say more than seven million people die from exposure to indoor or outdoor air pollution each year. Of that number, the WHO says about 4. 3 million people die from household air pollution given off by simple coal cook-stoves. Most of the deaths are in developing countries.

Carlos Dora is Coordinator in the WHO's Department of Public Health, Environmental and Social Determinants of Health. He says people should not use unprocessed coal and kerosene fuel indoors. He says opening a window or door to let out the harmful air will not improve the situation. It will only pollute the outdoors.

WHO officials say indoor pollution leads to early deaths from stroke, heart and lung disease, childhood pneumonia（肺炎） and lung cancer. Women and girls are the main victims. The United Nations found that more than 95 percent of households in sub-Saharan Africa depend on solid fuels for cooking. It says huge populations in India, China and Latin American countries, such as Guatemala and Peru, are also at risk.

Nigel Bruce is a professor of Public Health at the University of Liverpool. He says researchers are developing good cook-stoves and other equipment to burn fuels in a more efficient way.

WHO experts note some new, safe and low-cost technologies that could help are already available. In India, you can buy an induction(電磁) stove for about $ 8.00. And in Africa a you can buy a solar lamp for less than $ 1. 00.

1.What has been done to reduce indoor air pollution?

A. The WHO provided selfless assistance for the poor.

B. People are forbidden to use coal-stoves inside.

C. The WHO issues official advice to cut down pollution,

D. People are taught how to correctly use their stoves.

2.According to WHO officials, we can know that

A. many people refuse to use clean fuels and technologies

B. seven million people die from indoor air pollution

C. simple coal cook-stoves cause too many deaths

D. the processed coal is dangerous to people’s heath

3.It can be concluded from the fifth paragraph that .

A. most children are suffering a lot from lung cancer

B. solid fuels are easily producing pollutants

C. sub-Saharan Africa is the poorest place

D. some countries are at the risk of using up fuels

4.What can we infer from the passage?

A. More and more will die in the future.

B. It is not hard to solve indoor air pollutants.

C. Most people cannot afford a new stove.

D. The WHO will take strong measures.

查看答案和解析>>

同步練習(xí)冊答案