Falling and gravity

About 400 years ago, Caltleo

noticed that objects speed up,

or accelerate, as they fall.

 

He found that heavy and light

things, of the same shape and

size, take the same time to fall

to the ground. Gravity pulls

then-* down equally.

 

Try this for yourself with

different objects, like a slipper :

and a heavy boot.

 

Air resistance

Objects of different shapes and

sizes fall at different rates.  The

shape of a parachute makes

people fall more slowly.

 

 

The air pushing

against the parachute

causes a lot of air

resistance*. A person

without a parachute

falls faster because less

air pushes against

them.

The faster something falls, the

more air resistance there is on

it. Eventually, the air resistance

 slowing it down becomes as

strong as the pull of gravity.

Then its speed no longer

changes. This is called terminal

speed.

Free fall

If there were no air, there would be no air

resistance. All falling objects would just get

faster and faster < called is This rate. same the>

free fall.

 

67. Falling objects are pulled down to the ground by   .  

A. gravity                         B. resistance              C. speed                   D. acceleration(加速度)  

68. Why do people make parachutes(降落傘)?  

A. To look pretty and colourful in the air.            B. To slow down the falling speed.  

C. To push against the air in the sky.                  D. To accelerate the falling movement.  

69. Which did Galileo discover?  

A. A heavy ball falls faster than a light ball.          B. A light ball falls faster than a heavy ball.  

C. A light ball and a heavy ball fall at the same speed

D. A light ball and a heavy ball fall at different speed.

70. Which of the following is NOT true according to the passage?

A. Heavy and light objects fall equally when they are different in size.

B. When air resistance equals gravity, objects fall at terminal speed.

C. Without air; all falling objects get faster and faster at the same rate.

D. Slippers(拖鞋) and boots (靴子)fall at the same speed because they have the same shape  

 

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科目:高中英語 來源: 題型:閱讀理解

把下列單詞填入每個(gè)句子的空白處(注意所填單詞的形式變化):

hero  quality  willing  active  republic  principle  fight  prison  period  advise  continue  youth  league  stage  vote  position  accept  violence peaceful  blanket  degree  guard  educated  terror  fear  cruelty   reward   criminal   president   sincerely

1 The Society for the Prevention of _________ to Animals (SPCA 動(dòng)物保護(hù)協(xié)會(huì)) is a well known organization in the world.

2 The girl wrapped herself with a _________ to keep herself warm.

3 The famous actress first appeared on the _________ only in her teens.

4 The two boys who were _________ in the playground were ordered to stop.

5 People regarded him as a ________, for he saved a drowning 8-year-old boy out of a freezing lake.

6 You really deserve a _________ for being so helpful.

7 My uncle received a doctor’s _________of medicine in America in 1998 and returned to China the following year.

8 He obtained 89% of the __________ and was elected president of the Party.

9 Nelson Mandela was put in ________ a few times.

10 People often value the _________ of a product rather than its packaging.

11 The _________ was charged with robbing a bank and sentenced to death.

12 Two soliders _________ the government office building all the time.

13 My father was promoted to a higher _________ for his achievements.

14 I stayed in Japan for only a short _________ of time.

15 Those boys are so helpful that they are always ________ to help others.

16 George Bush was elected _________ of the USA a second time in 2004.

17 All my family are well _________, of whom my brother studied in Harvard University.

18 I am a Party member and never ________any bribe(賄賂) from others.

19 The doctor _________ me to take more exercise so that I can keep fit.

20 Some students are very ________ in answering teachers’ questions while others just keep silent when asked any question.

21 I _________ hope that you won’t let me down.

22 To his ________, he found a figure coming towards him in the darkness.

23 What really worries those parents is that there is too much sex and _______ on TV.

24 The rain ________ falling all afternoon. But it came to a stop by dark.

25 PRC is short for the People’s _________ of China.

26 His son has been missing for five days and now police are beginning to _______ the worst.

27 After retirement she moved to the country and lived a ________ life.

28 The _________ play an important role in building our country.

29 I have been a ________ member for 3 years.

30 Stick to your ________ and tell him that you won’t do it.

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科目:高中英語 來源:廣東省普寧市20092010學(xué)年高一上學(xué)期必修一水平測試試卷(英語) 題型:完型填空

第二部分語言知識(shí)及應(yīng)用(共兩節(jié), 滿分35分)

第一節(jié):完形填空(共10小題,每小題2分,滿分20分)

閱讀下面短文,掌握其大意,然后從21—30各題所給的四個(gè)選項(xiàng)(A、B、C和D)中,選出最佳選項(xiàng),并在答題卡上將該項(xiàng)涂黑。

The Guardian newspaper once printed a story about a man who tripped over his shoelace in the Fitzwilliam Museum in Cambridge. Falling down some steps, he ___21____ three priceless Qing Dynasty vases, which fell to the ground and broke into more than 400 pieces. He was sitting there in ___ 22___ when the museum staff arrived. Everyone stood around in silence --- only the man kept pointing to the ___23___, saying, “There it is! That’s what made me fall.”

Man has been blaming others at least since Adam blamed Eve, and Eve blamed the serpent(蛇). Roman emperors liked to kill ____ 24___ who brought bad news; and in the Middle Ages a prince would often be given a “whipping boy” --- an unlucky servant who could be ___25____ whenever his master had misbehaved. Today, you’ll see how blaming others has turned into big __26_____ business. In one famous case, McDonald’s was ordered to pay $2.7 million to a woman who ____27____ burned herself with hot coffee. Although the amount was later ___28_____ to $480,000, this case ____29___ businesses so much that they began to create 30   for their products that even an idiot(傻子)would understand. For example, “Hot coffee can be dangerous” (take away coffee cups) and “Don’t pour liquids into your television set” (instruction booklet).

21. A. broke down         B. knocked over            C. crashed into              D. slid down

22. A. terror                 B. amazement               C. sadness                     D. shock

23. A. shoelace              B. vase                         C. steps                        D. pieces

24. A. servants                     B. ministers                  C. messengers               D. slaves

25. A. killed                 B. sentenced                 C. rewarded                  D. beaten

26. A. legal                  B. public                      C. lawless                     D. legendary

27. A. deliberately         B. accidentally                     C. carelessly                 D. attentively

28. A. increased            B. reduced                    C. raised                   D. dropped

29. A. surprised             B. excited                     C. inspired                    D. terrified

30. A. advertisements  B. posters                  C. warnings                  D. instructions

 

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科目:高中英語 來源:上海市2010屆高三上學(xué)期摸底考試 題型:閱讀理解

D

The eruption of a volcano in the Canary Islands could trigger a “mega-tsunami”(巨大海嘯)that would hit Atlantic coastlines with waves as high as 330 feet, scientists said on Wednesday. They said an eruption of the Cumbre Vieja volcano on La Palma, part of the Spanish island chain off West Africa, was likely to cause a massive chunk(大塊)of rock to break off, crashing into the sea and kicking up huge walls of water higher than any other in recorded history. The tsunami would be capable of traveling huge distances at up to 500 miles an hour, the scientists said in a research paper to be published soon.

Simon Day, of the Benfield Greig Hazard Research Centre at the University College of London, said that as the volcano was not erupting at present, the short-term and medium-term risks were “negligible”. But Cumbre Vieja should be monitored closely for any signs of activity so that emergency services could plan an effective response, he said. “Eruptions of Cumbre Vieja occur at intervals of decades to a century or so and there may be a number of eruptions before its collapse(倒塌),” said Day, who cooperated on the research with Steven Ward of the University of California. “Although the year-to-year probability of a collapse is therefore low, the resulting tsunami would be a major disaster with indirect effects around the world.”

The effects would spread north, west and south of the Canaries, with the west Sahara bearing the worst of the wave’s energy. The energy released by the collapse would be equal to the electricity consumption of the entire United States in half a year.

Immediately after the landslide(山崩),a huge wave of water 93,000 feet high and tens of miles wide would form. As the landslide rocks moved deeper under water, a tsunami would develop. Within 10 minutes, the tsunami would have moved a distance of almost 155 miles. On the west Saharan shore, waves would probably reach heights of 330 feet.

Florida and the Caribbean, the final north Atlantic destinations to be affected by the tsunami, would have to brace themselves for 165-foot waves some eight to nine hours after the landslide. Wave heights toward Europe would be smaller, but substantial waves would hit the coasts of Britain, Spain Portugal and France. The research paper estimated water would penetrate several miles inland and that the devastation would cause trillions of dollars in damage.

76. What would be the result of a big chunk rock falling into the sea?

A. Waves would be very high.                                         B. The volcano would stop.

C. Walls of water would kick up a storm.                          D. An earthquake would take place.

77. The word “negligible”(Line 3, Paragraph 2) is closest in meaning to ______.

A. unimportant                    B. small                              C. predictable               D. avoidable

78. From the passage we may learn that the volcano erupts ______.

A. every year                                                                 B. every 5 to 9 years

C. every 10 to 100 years                                                        D. every 5 to 10 months

79. All of the following are true EXCEPT ______.

A future eruption of Cumbre Vieja volcano may experience a massive collapse

Waves generated by the landslide could even reach the coasts of the United States

The landslide-released energy is equal to half a year’s electricity consumption in the US

American scientists have managed to utilize the volcanic energy for civil purposes

 

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科目:高中英語 來源:2010-2011學(xué)年湖南省高三上學(xué)期第四次月考英語卷 題型:閱讀理解

According to legend, the Bridge of Sighs in Venice, Italy, which connects the Palazzo Ducale to an ancient prison, got its name because the walk across it gave prisoners on their way to jail a final chance to appreciate the beauty of the city.

The view from the bridge today, however, is more likely to be of a giant billboard selling Bulgari or Coca – cola. Beyond the billboards, monuments are being restored. The money comes from advertising profits.

But when the Coke billboards went up this summer on buildings near the Piazza San Marco, which is at the historic heart of Venice, there was a public debate.

“We can’t commercialize everything,” said Alessandra Mottola Molfino, a Venetian. “The lesson that goes out is that a price is for everything.”

“We couldn’t stay quiet,” said Maria Camilla Bianchini d’Alberigo, president of a heritage protection association. “Too much is too much.”

There needed to be rules, she added, rules that prevent the advertising billboards clashing (沖突) with the monuments of the city.

City of officials, however, argue that without these ads, the city could not afford to maintain its heritage. Many have been damaged by centuries of wear and are even a threat to public safety.

“I can’t turn down the image of bottle when there are pieces of the Palazzo Ducale falling to the ground,” said Renata Codello, a Cultrue Ministry official.

The Culture Minister has a budget of about $ 47 million (315 million yuan) for restoration of monuments, but Italy has a rich architectural heritage, and funds are always tight.Of that amount,

$ 1.8 million was given to the entire Vector region,  which includes Venice.

Two years ago, the city signed an agreement with the Dotter Group, a company responsible for the restoration of the Bridge of Sighs and the Palazzo Ducale.It allows it to sell ad space.

But there is a condition in the agreement: The ads should not offend public taste,

In August, Venice banned US actress Julianne Moore's Bulgrari ad from a billboard in the Piazza San Marco.

The photo shows a naked Moore covered with lion cubs, handbags and jewelry, Mayor Giorgio Orsoni called the image too racy (猥褻) and unsuitable for the Piazza San Marco.

"I take account of the fact that Venice is part of the real world… but we cannot accept these Hollywood-style images.There arc intelligent sponsors, and we need to come up with advertising that suits Venice, not Times Square," he said in a speech.

1.The article is mainly about        in Venice

A.restoration of cultural heritage

B.widespread commercialization

C.the conflict between ads and cultural heritage

D.the difficulty of restoring monuments

2.In the first paragraph, the beautiful view from the Bridge of Sighs is mentioned to      .

A.introduce other monuments of the ancient city

B.show how much many ancient structures need restoring

C.indicate that the view is blocked by huge ads

D.create interest in the famous city

3.From the article we can conclude that Rcnata Codello        the advertising.

A.is in favor of

B.is worried about

C.objects to

D.doesn't mind

4.Why do many Venetians complain about the ads?

A.They are intolerant of commercialization.

B.They feel the ads are damaging the city.

C.The ads are usually racy and in an American style.

D.The ads don't present a traditional view of Venice,

5.It can be inferred from the passage that

A.Hollywood stars' ads cannot go up in Venice

B.the mayor of Venice is expecting new advertising

C.the Dotter Group may stop its restoration work for lack of funds

D.people can buy Bulgaria or Coca-cola on the Bridge of Sighs

 

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科目:高中英語 來源:2010溫州中學(xué)高二下學(xué)期期末考試 題型:閱讀理解

MONTREAL--He may be the world’s richest man, but that didn’t prevent Bill Gates from falling for an April Fool’s day joke by two Quebec radio comics (喜劇演員) pretending to be Canadian Prime Minister Jean Chretien.

Montreal French-language station CKMF--FM said last Wednesday that staffers (工作人員) Marcantoine Audet and Sebastien Trudel had a 10-minute telephone chat with Microsoft Corp boss Gates on April 1.

The broadcast was aired on their nightly show last Tuesday and repeated last Wednesday.

“We were happy. We had been calling Microsoft persistently (堅(jiān)持不懈地) for four weeks,” Trudel said.

Trudel said he and his colleague had already fooled Canadian pop singer Celine Dion and Formula One (一級(jí)方程賽車) driver Jacques Villeneuve on their show.

“This time, we wanted to give ourselves a challenge with somebody more difficult to reach,” Ttudel said.

He said he was surprised that Gates’s assistants did not check to see if it was really the prime minister’s office on the line.

Trudel said they imitated (模仿) Chretien’s heavily accented English, talking about the economy, asking about Microsoft’s Windows operating system and inviting the multibillionaire to visit a well-known Montreal strip joint (運(yùn)動(dòng)服合資企業(yè)).

The radio host said that Gates was not amused by the fake interview.

“He did not seem angry but he did not find it so funny,” the comic said.

1.Bill Gates was fooled mainly because ______.

A.his assistants were not careful enough

B.the Canadian Prime Minister helped the two comics

C.the two comics imitated the Canadian Prime Minister so well

D.it was April Fool’s Day

2.We can conclude from the passage that the two comics ______.

A.liked to fool famous people on their show 

B.thought that Gates was not a great challenge to them

C.had a good knowledge of Bill Gates and his Windows operating system

D.were not quite satisfied with their tricks

3.Which of the following would be the best title of the passage?

A.Gates ‘April Fooled’

B.Two Comics and Their Tricks

C.Two comics and Their Show

D.A Fake Interview

 

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