网址:http://m.1010jiajiao.com/timu3_id_3022013[举报]
The day after news broke of a possible revolution in physics ——particles (粒子) moving faster than light ?a scientist leading the European experiment that made the discovery calmly explained it to a standing-room- only crowd at CERN.
The physicist, Dario Auterio, did not try to explain what the results might mean for the laws of physics, let alone the broader world.After an hour of technical talk, he simply said, "Therefore, we present to you today this difference, this unusualness."
But what unusualness it may be.From 2009 through 2011, the massive OPERA detector (探测器)buried in a mountain in Gran Sasso, Italy, recorded subatomic particles called neutrinos ( 中微子) arriving faster than light can move in an empty space.The neutrinos generated at CERN are hardly detectably early.If confirmed, the finding would throw more than a century of physics into disorder.
"If it's correct, it's phenomenal." said Rob Plunkett, a scientist at Fermilab, the Department of Energy physics laboratory in Illinois."We'd be looking at a whole new set of rules" for how the universe works.Those rules would bend, or possibly break, Albert Einstein's special theory of relativity, published in 1905.Basical at the time, the theory tied together space and time, matter and energy, and set a hard limit for the speed of light, later measured to be about 186, 000 miles per second.
No experiment in 106 years had broken that speed limit.Physicists expect strict study to follow, which OPERA and CERN scientists welcomed.
Fermilab operates a similar experiment, called MINOS, that shoots neutrinos from Illinois to an underground detector in Minnesota.In 2007, MINOS discovered a just detectable amount of faster than-light neutrinos, but the permissible difference of error was too big to "mention" , Plunkett said.
Fermilab scientists will reanalyze their data, which will take six to eight months.In 2013, the MINOS detector, now offline, will restart after an upgrade.It could then offer confirmation of the results.
【小题1】Why are the European scientists not sure about the results of the experiment?
A.Because they are so unexpected. |
B.Because the scientists do not believe them. |
C.Because the scientists are careful and calm. |
D.Because they are against the present law of physics. |
A.amazing | B.attractive | C.embarrassing | D.sensitive |
A.Are the laws of physics in disorder? |
B.Particles faster than light; Revolution or mistake? |
C.Faster than light measurement: right or wrong? |
D.Is Einstein's theory still right today? |
A.Different opinions about the experiment. |
B.How Albert Einstein's theory developed. |
C.The new rules for how the universe works. |
D.How Fermilab scientists will reanalyze their data. |
The Internet has led to a huge increase in credit-card fraud. Your card information could even be for sale in an illegal website. Websites offering cheap goods and services should be regarded with card. On line, shoppers who enter their credit-card information may never receive the goods they thought they bought. The thieves then go shopping with your card number—or sell the information over the Internet.
Computer hackers have broken down security system and that raises questions about the safety of card-holder information.
Several months ago, 25,000 customers of CD universe, an on-line music retailer (批发商), were not lucky. Their names, addresses and credit-card numbers were posted on a website after the retailer refused to pay US $157,828 to get back the information.
Credit-card firms are now fighting against online fraud. Master-card is working on plans for web-only credit-card, with a lower credit limit. The card could be used only for shopping online. However, there are a few simple steps you can take to keep from being cheated.
Ask about your credit-card firm’s online rules: Under British law, cardholders are responsible for the first US $ 78 of any cheating spending.
And shop only at secure sites: Send your credit-card information only if the website offers advanced secure system.
If the security is in place, a letter will appear in the bottom right-hand comer of your screen. The website address may also start https://—the extra "s" stands for secure. If in doubt, give your credit-card information over the telephone.
Keep your password safe: Most on-line sites require a user name and password before placing an order. Treat your password with care.
1. The underlined word “fraud” in the first paragraph probably means_____________.
A. cheating B. sale C. payment D. use
2. According to this passage most people worry about shopping on the Internet because___________.
A. many stolen credit-cards are sold on the Internet every day
B. fraud on the Internet happens very often
C. many websites break down every day
D. there are too many illegal websites on the Internet
3. Thieves usually get the information of the credit-card, ______.
A. because many customers lost their cards
B. by paying money for people working in the information companies
C. because the customers tell them their password
D. by stealing the information from websites
4. The best title for the passage might be________.
A. How to Beat Online Credit-card Thieves
B. How to Shop on the Internet
C. Never Use Credit Cards without an Advanced Computer
D. Why Thieves Steal Credit-card Information
查看习题详情和答案>>The day after news broke of a possible revolution in physics ——particles (粒子) moving faster than light ?a scientist leading the European experiment that made the discovery calmly explained it to a standing-room- only crowd at CERN.
The physicist, Dario Auterio, did not try to explain what the results might mean for the laws of physics, let alone the broader world.After an hour of technical talk, he simply said, "Therefore, we present to you today this difference, this unusualness."
But what unusualness it may be.From 2009 through 2011, the massive OPERA detector (探测器)buried in a mountain in Gran Sasso, Italy, recorded subatomic particles called neutrinos ( 中微子) arriving faster than light can move in an empty space.The neutrinos generated at CERN are hardly detectably early.If confirmed, the finding would throw more than a century of physics into disorder.
"If it's correct, it's phenomenal." said Rob Plunkett, a scientist at Fermilab, the Department of Energy physics laboratory in Illinois."We'd be looking at a whole new set of rules" for how the universe works.Those rules would bend, or possibly break, Albert Einstein's special theory of relativity, published in 1905.Basical at the time, the theory tied together space and time, matter and energy, and set a hard limit for the speed of light, later measured to be about 186, 000 miles per second.
No experiment in 106 years had broken that speed limit.Physicists expect strict study to follow, which OPERA and CERN scientists welcomed.
Fermilab operates a similar experiment, called MINOS, that shoots neutrinos from Illinois to an underground detector in Minnesota.In 2007, MINOS discovered a just detectable amount of faster than-light neutrinos, but the permissible difference of error was too big to "mention" , Plunkett said.
Fermilab scientists will reanalyze their data, which will take six to eight months.In 2013, the MINOS detector, now offline, will restart after an upgrade.It could then offer confirmation of the results.
- 1.
Why are the European scientists not sure about the results of the experiment?
- A.Because they are so unexpected.
- B.Because the scientists do not believe them.
- C.Because the scientists are careful and calm.
- D.Because they are against the present law of physics.
- A.
- 2.
The underlined word " phenomenal" in the fourth paragraph has the closest meaning to .
- A.amazing
- B.attractive
- C.embarrassing
- D.sensitive
- A.
- 3.
The best title for the passage may be _____.
- A.Are the laws of physics in disorder?
- B.Particles faster than light; Revolution or mistake?
- C.Faster than light measurement: right or wrong?
- D.Is Einstein's theory still right today?
- A.
- 4.
What may be discussed in the paragraphs to follow?
- A.Different opinions about the experiment.
- B.How Albert Einstein's theory developed.
- C.The new rules for how the universe works.
- D.How Fermilab scientists will reanalyze their data.
- A.
The day after news broke of a possible revolution in physics ——particles (粒子) moving faster than light ?a scientist leading the European experiment that made the discovery calmly explained it to a standing-room- only crowd at CERN.
The physicist, Dario Auterio, did not try to explain what the results might mean for the laws of physics, let alone the broader world.After an hour of technical talk, he simply said, "Therefore, we present to you today this difference, this unusualness."
But what unusualness it may be.From 2009 through 2011, the massive OPERA detector (探测器)buried in a mountain in Gran Sasso, Italy, recorded subatomic particles called neutrinos ( 中微子) arriving faster than light can move in an empty space.The neutrinos generated at CERN are hardly detectably early.If confirmed, the finding would throw more than a century of physics into disorder.
"If it's correct, it's phenomenal." said Rob Plunkett, a scientist at Fermilab, the Department of Energy physics laboratory in Illinois."We'd be looking at a whole new set of rules" for how the universe works.Those rules would bend, or possibly break, Albert Einstein's special theory of relativity, published in 1905.Basical at the time, the theory tied together space and time, matter and energy, and set a hard limit for the speed of light, later measured to be about 186, 000 miles per second.
No experiment in 106 years had broken that speed limit.Physicists expect strict study to follow, which OPERA and CERN scientists welcomed.
Fermilab operates a similar experiment, called MINOS, that shoots neutrinos from Illinois to an underground detector in Minnesota.In 2007, MINOS discovered a just detectable amount of faster than-light neutrinos, but the permissible difference of error was too big to "mention" , Plunkett said.
Fermilab scientists will reanalyze their data, which will take six to eight months.In 2013, the MINOS detector, now offline, will restart after an upgrade.It could then offer confirmation of the results.
72.Why are the European scientists not sure about the results of the experiment?
A.Because they are so unexpected.
B.Because the scientists do not believe them.
C.Because the scientists are careful and calm.
D.Because they are against the present law of physics.
73.The underlined word " phenomenal" in the fourth paragraph has the closest meaning to .
A.amazing B.attractive C.embarrassing D.sensitive
74.The best title for the passage may be _____.
A.Are the laws of physics in disorder?
B.Particles faster than light; Revolution or mistake?
C.Faster than light measurement: right or wrong?
D.Is Einstein's theory still right today?
75.What may be discussed in the paragraphs to follow?
A.Different opinions about the experiment.
B.How Albert Einstein's theory developed.
C.The new rules for how the universe works.
D.How Fermilab scientists will reanalyze their data.
查看习题详情和答案>>When you think about math, you probably don’t think about breaking the law, solving mysteries or finding criminals. But a mathematician in Maryland does, and he has come up with mathematical tools to help police find criminals.
People who solve crimes look for patterns that might reveal (揭示) the identity of the criminal. It’s long been believed, for example, that criminals will break the law closer to where they live, simply because it’s easier to get around in their own neighborhood. If police see a pattern of robberies in a certain area, they may look for a suspect who lives near the crime scenes. So, the farther away from the area a crime takes place, the less likely it is that the same criminal did it.
But Mike O’Leary, a mathematician at Towson University in Maryland, says that this kind of approach may be too simple. He says that police may get better clues to the location of a criminal’s home base by combining these patterns with a city’s layout (布局) and historical crime records.
The records of past crimes contain geographical information and can reveal easy targets — that is, the kind of stores that might be less difficult to rob. Because these stores are along roads, the locations of past crimes contain information about where major streets and intersections are. O’Leary is writing a new computer program that will quickly provide this kind of information for a given city. His program also includes information about the people who live in the city, and information about how a criminal’s patterns change with age. It’s been shown, for example, that the younger the criminal, the closer to home the crime.
Other computer programmers have worked on similar software, but O’Leary’s uses more math. The mathematician plans to make his computer program available, free of charge, to police departments around the country.
The program is just one way to use math to fight crime. O’Leary says that criminology — the study of crime and criminals — contains a lot of good math problems. “I feel like I’m in a gold mine and I’m the only one who knows what gold looks like,” he says. “It’s a lot of fun.”
61. To find criminals, police usually _________.
A. check who are on the crime scene
B. seek help from local people
C. depend on new mathematical tools
D. focus on where crimes take place
62. O’Leary is writing a computer program that _________.
A. uses math to increase the speed of calculation
B. tells the identity of a criminal in a certain area
C. provides the crime records of a given city
D. shows changes in criminals’ patterns
63. By “I’m the only one who knows what gold looks like”, O’Leary means that he _________.
A. is better at finding gold than others
B. is the only one who uses math to make money
C. knows best how to use math to help solve crimes
D. has more knowledge of gold than other mathematicians
64. What do you know about O’Leary according to the passage?
A. He is a man full of impractical imagination.
B. He is a man full of self-confidence.
C. He is a man who is talkative but lazy.
D. He is a man who doesn’t like mathematics.
65. What is the main idea of the text?
A. Math could help police find criminals.
B. Criminals live near where crimes occur.
C. Crime records could be used to fight crime.
D. Computer software works in preventing crimes.