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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 (隐形斗篷) 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. ”
The first two paragraphs serve as a (n) ________.

A.introduction B.explanation
C.comment D.summary

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

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

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
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Cheaters called “pirates” often use camcorders(便携式摄像机) and cell phones to make illegal copies of blockbusters(大片) in the local theater. These pirates then sell those recordings on the street or over the Internet for very low prices. Some share them for free.
“It’s unfair for people to pirate movies, ” says 15-year-old Hadaia Azad Ezzulddin. Movie piracy “takes money out of the pockets of thousands of people in the movie industry,” she notes. Victims include famous actors and directors as well as local theater owners and their employees.
Hadaia came up with an idea that could help stop movie piracy. Hadaia’s idea uses infrared(红外线的) light. This range of light is invisible to the human eye. It is visible, however, to many types of cameras. Theater owners could place small infrared lights on their movie screens. The lights would not disturb people watching the movie. It would, however, distort the recordings made by many types of cameras.
To test her idea, Hadaia built a box with a movie screen inside. Then, she projected images on that screen through a hole in the box. She took recordings of those images, using nine different types of cameras. These included the types found in cell phones as well as camcorders. During some tests, she also turned on light emitting diodes(发光二极管), or LEDs. The LEDs were embedded(植入的) in a certain place behind the movie screen. They gave out infrared light.
Sure enough, she showed, a pirated movie included odd stripes or spots if it had been recorded while the LEDs were on. It might be possible to use the LEDs to flash the date and time on the movie screen. The information would then appear in the illegal recordings. Theater owners or police might use the information to track down the pirates.
Cutting down on piracy might get more people into theaters to watch the real movie instead of an illegal copy. Six out of every ten films now produced aren’t profitable. They don’t make enough money to recover how much was spent to make and market them. Such a poor payback can discourage filmmakers from producing anything but the types expected to become blockbuster hits. It might also keep smaller theaters from showing a wider variety of movie types.
From what Hadaia says in Paragraph 2, we can infer that _______.

A.she strongly criticizes those who video movies in the theater
B.the pirates don’t have to pay for the movie tickets
C.theater owners will increase the price of movie tickets
D.most people spend less money on pirates moves

Infrared lights are put on the movie screens to _______.

A.adjust the brightness of the movie screens
B.make sure the images of movies are dark
C.make illegal copies of movies unpleasant to see
D.protect the eyesight of viewers in the darkness

What is the correct order of the steps in Hadaia’s test?
a. She projected pictures on the screen.
b. She used cameras to record the pictures.
c. She turned on the LEDs placed behind the screen.
d. She made a special box with a movie screen inside.

A.bacd B.bcad C.dbac D.dcab

According to the last paragraph, we can know that _______.

A.small theaters often choose to show low-cost movies
B.forty percent of movies now are profitable
C.more and more people go to theaters to fight movie piracy
D.filmmakers prefer to produce ordinary movies than blockbusters

TIME is an American weekly news magazine published in New York City. It was created in 1923 by Briton Hadden and Henry Luce, making it the first weekly news magazine in the US. Hadden was considered carefree, liked to tease Luce and saw TIME as important but also fun. That accounted for its heavy coverage of celebrities(including politicians), the entertainment industry, and pop culture—criticized as too light for serious news.
It tells the news through people, and for many decades, the magazine’s cover depicted a single person. On Hadden’s death in 1929, Luce became the most important man at TIME and a major figure in the history of 20th-century media.
TIME is also known for its signature red border, first introduced in 1927. It has only changed four times since then. The issue released shortly after the September 11 attacks on the United States featured a black border to symbolize mourning. However, this edition was a special “extra” edition published quickly for the breaking news of the event; the next regularly scheduled issue contained the red border. Additionally, the April 28, 2008 Earth Day issue, dedicated to environmental issues, contained a green border. The next change in border was in the September 19, 2011 issue, commemorating the 10th anniversary of the September 11 attacks with a metallic silver border. The most recent change(again with a silver border) was in the December 31, 2012 issue, noting Barack Obama’s selection as Man of the Year.
TIME has a division magazine, TIME FOR KIDS(TFK), which is especially published for children and is mainly distributed in classrooms. TFK contains some national news, a “Cartoon of the Week”, and a variety of articles concerning popular culture that the younger U.S. citizens are interested in. All the stories in TFK are written by young reporters.
In some advertising campaigns, the magazine has suggested that the letters TIME stand for “The International Magazine of Events”.
TIME has a history of _______.

A.about 90 years B.about 70 years
C.about 50 years D.about 150 years

Why did some people dislike TIME in the beginning?

A.It had kept its cover the same since the 1920s.
B.It didn’t report important events quickly enough.
C.It didn’t have a serious tone for important events.
D.Henry Luce was in charge of the magazine for too long.

Why did TIME change its red border for the first time?

A.To remember the 10th anniversary of an attack.
B.To show great sadness about the deaths.
C.To remind readers to protect the environment.
D.To call on readers to vote for Obama.

What do we know about TFK?

A.It mainly contains popular culture.
B.It has a division magazine called TIME.
C.It is designed for kids and teachers.
D.It has young reporters writing articles.

Deborah Cohen is a senior natural scientist at the Rand Corp and the author of the book A Big Fat Crisis: The Hidden Forces Behind the Obesity Epidemic and How We Can End It. According to the book, there are lots of misunderstandings of obesity.
1. If you’re obese, blame your genes.
Obesity rates have increased. Yet, between 1980 and 2000, the number of Americans who are obese has doubled—too quickly for genetic factors to be responsible.
At restaurants, a dollar puts more calories on our plates than ever before, because restaurant meals usually have more calories than what we prepare at home, so people who eat out more frequently have higher rates of obesity than those who eat out less.
2. If you’re obese, you lack self-control.
Research shows that if we are faced with too much information, we have a tendency to make poor dietary choices. Our world has become so rich in temptation that we can be led to consume too much in ways we can’t understand. Even the most vigilant(警觉的) people may not be up to the task of controlling themselves.
3. Lack of access to fresh fruits and vegetables is responsible for obesity.
Although the US Department of Agriculture estimates that fewer than 5 percent of Americans live in the “food deserts”, about 65 percent of the nation’s population is overweight or obese. For most of us, obesity is not related to access to more fresh fruits and vegetables, but to the choices we make in supermarkets.
4. The problem is not that we eat too much, but that we don’t exercise.
Michelle Obama’s “Let’s Move” campaign is based on the idea that if kids exercise more, childhood obesity rates will decrease. But there was no significant decrease in physical activity levels as obesity rates climbed in the 1980s and 1990s. In fact, although a drop in work-related physical activity may account for up to 100 fewer calories burned, leisure physical activity appears to have increased. The problem is that we eat too much.
The author mentioned Deborah Cohen’s book in Paragraph 1 to _______.

A.draw readers’ attention
B.introduce the topic
C.introduce the author of the book
D.advertise the book

What is the relationship between obesity and the place where you eat?

A.The more you eat out, the higher rates of obesity you have.
B.The less you eat at home, the lower rates of obesity you have.
C.The less you eat out, the higher rates of obesity you have.
D.The more you eat at home, the higher rates of obesity you have.

What’s the best title of this passage?

A.Obesity leads to a big fat crisis.
B.Four rules to help you avoid obesity.
C.Four misunderstandings of obesity.
D.Lacking self-control leads to obesity.

Both of Jessica’s parents were lawyers and expected her to follow suit. So she went to law school, got a job at a great firm in Washington, DC, and worked as a lawyer for a decade. But her heart was never in it. “I had a big salary but no personal satisfaction,” she says.
Jessica found pleasure in the same thing that had brought her joy since joining the church choir at the age of 12. “Singing always felt like communicating something real at a spiritual and emotional level,” says Jessica. Yet she never considered it a career option. “That seemed like something people did in fairy tales, and I would never let my parents down,” she says.
It was her mom’s diagnosis of brain cancer in 2009 that made Jessica realize she had to write her own happy-ever-after. “Work was busy and my mother was ailing. So I was flying back and forth from Washington, DC to Houston to see her,” Jessica says. “I finally said, ‘Enough!’ and quit.” While caring for her mom, Jessica made a plan. She would spend her savings and study music for a year, and then open a part-time law practice so she could pursue her passion. Before her mother passed away two years later, she encouraged Jessica to follow her dream. Her song Live This Life was inspired by her mom, and her dad came to watch her perform at clubs.
In 2012, Jessica moved to Nashville to try singing and songwriting. A decade of presenting cases in court gave her the confidence to sing for a crowd. “At 20, I would have been too shy to perform,” says Jessica.
“Doing music is so free,” Jessica says. “There’s no pressure to be a star. Success, to me, isn’t a dollar amount or a record deal; it’s doing what I love.”
Which of the following is TRUE?

A.Jessica wasn’t satisfied with the pay she got as a lawyer.
B.Jessica didn’t know what she truly loved for ten years.
C.Jessica didn’t really like working as a lawyer.
D.Jessica was grateful for her parents’ arrangement for her.

What does the underlined word “ailing” in Paragraph 3 mean?

A.Crazy. B.Sick.
C.Worried. D.Unhappy.

What was Jessica’s mother’s attitude toward her singing?

A.Supportive. B.Doubtful.
C.Negative. D.Unknown.

By telling Jessica’s story, the writer most probably wants to _______.

A.show that family members’ support is important
B.show that singing can be a practical career
C.tell us the importance of choosing a right job
D.encourage us to pursue our dreams

Never Talk to Strangers?
“Never talk to strangers.” Many children are taught this simple rule as a precaution against abduction(诱拐). In June, 2005, an 11-year-old boy was lost in the Utah wilderness for four days. During that time, he stayed on the path. He saw people searching for him but deliberately hid from them, afraid someone might “steal” him. Eventually, the unfortunate game of hide-and-seek ended and he was found. According to the Canada Safety Council, this alarming incident shows how unwise it is to instill(灌输) a fear of strangers in children. The “stranger danger” message can prevent children from developing the social skills and judgment needed to deal effectively with real-life situations. In a difficult situation, a stranger could be their lifeline to safety.
To have a child go missing is a parent’s worst nightmare. The threat of abduction by a stranger is minimal when compared with other possible reasons for a disappearance. In 2004, there were 67,266 missing-children cases in Canada. Only 31 involved abduction; in most of those cases the abductor was a relative, friend, or person known to the family. There were 671 cases of children wandering off, and 332 cases of abductions by a parent. Almost 80 percent of all cases were runaways. These statistics cast doubt on the idea that children should never talk to strangers. Wandering off is more common—but a lost children may have to call upon a stranger for help, and must develop the ability to judge what kind of people to approach. The “never talk to strangers” rule does not protect children in the situations they are most likely to face. On top of this, it can be confusing. Adults do not model the behaviour; they often talk to strangers. A child may not know how to tell who is a stranger, and who is not.
For young children, nothing replaces close supervision(监管). Pre-schoolers do not understand risk and tend to act without thinking. Children need to develop habits and sttitudes that will protect them from the real threats and dangers they may face. The Canada Safety Council encourages parents to give their children age-appropriate positive messages about safety, bearing in mind how youngsters may understand their world.
Which of the following statements is NOT true about the 11-year-old boy?

A.He practiced the “never talk to strangers” rule.
B.He hid from the rescuers to avoid possible abduction.
C.He eventually showed up when his hide-and-seek game ended.
D.He stayed where he was, expecting the coming of familiar people.

Among the possible reasons for the missing-children cases in Canada, which one is the most frequent?

A.Being abducted by a parent. B.Wandering off.
C.Being abducted by strangers. D.Running away.

The “never talk to strangers” rule is confusing to children because ___.

A.a friendly and attractive person may be dangerous
B.adults do not act upon the rule and strangers are hard to tell
C.the rule does not protect children in the situation of abducting
D.a lost child may have difficulty in communicating with a stranger

Which would the author agree with about the “never talk to strangers” rule?

A.It is not well recognized by parents.
B.It is not effective in keeping kids safe.
C.It is easy enough for children to follow.
D.It is practical as a safety tip in daily life.

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