Temperature is measured by means of a thermometer (溫度計). One general form of thermometer depends upon the fact that most solids and liquids expand as their temperature rises. There are one or two exceptions. There is, for instance, a kind of steel called invar (from “invariable”) which does not change its dimensions as temperature changes; it is valuable for making pendulums (鐘擺), since, if the length of a pendulum changes, its time of vibration changes. It is also used for making very accurate measuring scales. In both cases, then, changes of atmospheric temperature have no effect if invar is used.

Another exception is that very odd liquid, water, which has many strange properties (特性). As water gets colder it contracts (收縮), which is ordinary behavior, until it reaches the temperature of 30℃. above freezing point. After that, as it gets colder, it expands. This is fortunate---for considering the freezing of a pond. As the water on top gets colder, it shrinks; and so, volume for volume, it becomes heavier and sinks. This goes on until all the pond is at 30℃, but after that, as the water becomes colder it expands. Therefore the colder water stays on top and freezes, covering the pond with ice. If the water went on contracting down to the freezing point, the pond would become a solid block of ice in the end. This would not worry people who live in hot climates, but it would be very serious for those who live in cold climates, especially for those who want to break the ice and catch fish which live in the cold water beneath.

1. Invar is valuable for making pendulums because _______.

A. it can hardly change its shape or size as temperature changes.

B. it will change its dimensions without the change of temperature.

C. its time of vibration doesn’t change if its length changes.

D. its time of vibration does not change if its length changes.

2. As water gets colder after reaching the temperature of 30℃. it will _______.

A. contract         B. shrink      C. expand           D. freeze

3. Which of the following statements is true, according to this passage?

A. Only invar can be used to make a thermometer.

B. Only water can be used to make a thermometer.

C. Both invar and water can be used to make a thermometer.

D. Neither invar nor water can be used to make a thermometer.

4.The best title of this passage is most likely to be  _____.

A. Temperature Measurement          B. Two Exceptions

C. Uses of Invar                        D. Properties of Water

 

 

【答案】

ACDB 

【解析】略

 

練習冊系列答案
相關(guān)習題

科目:高中英語 來源:2012-2013學年湖南省高三第五次月考英語卷(解析版) 題型:其他題

Marley is a businessman. His business is freezing people. He works for a company in California called Trans Time. Trans Time freezes people after they die. Why does Trans Time freeze people? Doctors today can cure many diseases, but they cannot cure all diseases. People still get sick and die. Maybe in the future doctors will have medicine for all diseases. Some people think so. They want Trans Time to freeze their bodies after they die. Maybe 100 or 200, or 300 years later, Trans Time doctors will bring the people back to life. The doctors will cure their diseases, and the people will be alive and healthy again.

People often ask the scientists at the Trans Time, “How will Trans Time bring dead people back to life?” They say, “We can freeze a healthy animal and bring it back to life. We think that someday it will be possible with human.” When they say “someday”, they mean years from now — maybe 100 or 200 years. How can Trans Time keep people frozen for 200 years?

After a person dies, workers at Trans Time cool the body with ice and chemicals. When the body is very cold, workers put the body into a capsule (密封艙). They fill the capsule with liquid nitrogen (液氮). The temperature in it is 196 degrees centigrade below zero. Every two weeks workers add more liquid nitrogen. The liquid nitrogen keeps the bodies frozen.

Trans Time charges $21,000 to freeze a body and $59,000 to keep a body frozen. That’s $80,000 all together. It is a lot of money. But some people think that $80,000 is a fair price. It’s a fair price for a chance to live again, isn’t it?

1.What kind of people does Trans Time serve? (No more than 2 words)

                                                                              

2.How much should one pay together, if he wants his body to be cooled and kept by Trans Time?

(No more than 2 words)

                                                                              

3.Why do people want to be frozen? (No more than 9 words)

                                                                              

4.What is the main idea of Paragraph 3? (No more than 6 words)

                                                                            

 

查看答案和解析>>

科目:高中英語 來源:2012屆重慶市“名校聯(lián)盟”高二第一次聯(lián)考英語試卷(解析版) 題型:閱讀理解

When we look at the sky and see a bright light moving quickly across it or coming towards the earth, we talk about seeing a “shooting star” or a “falling star”. These moving lights are not, in fact, stars at all. They are small pieces of matter from outer space, which burn up as they enter the Earth’s atmosphere. The correct name of them is meteoroids. Any pieces that make it to the Earth’s surface without completely burning up are known as meteorites. A meteor is actually the name given to the light we see when a meteoroid is burning up.

When a meteorite hits the Earth at speeds between 11 and 72 kilometers a second, it can do amazing damage. A very large meteorite could knock the earth out of its orbit. If this happened, all life on Earth would probably become extinct(滅絕). The path we follow around the Sun would change and as a result the Earth would become either much hotter or much colder. This change in temperature would affect sea levels and the amount of water in rivers. There would either be huge floods, which would cover most of the land with water, or the oceans would dry up and there would be a drought, which means a long period of time without rain. Either way, nothing could survive. If a large meteorite landed in the sea it would almost certainly cause tsunamis, which would race towards the land, destroying everything in their paths.

Although it is unlikely the Earth will be struck by a meteorite large enough to do that kind of damage, there is evidence of fairly large meteorites hitting the Earth in the past. In 1908 a large area of forest in Tunguska, Siberia was destroyed by a meteorite that came apart just before it hit the ground. The moon, however, has about three billion craters隕石坑caused by meteorites impacting影響 its surface. The reason more meteorites have reached the surface of the moon than the surface of the Earth is that the moon does not have enough atmosphere for the meteorites to burn up in. some of the meteorites that have reached the Earth’s surface have done considerable damage. Some scientists believe it was a change of climate caused by meteorites hitting the Earth that resulted in the extinction of the dinosaurs and other large prehistoric animals.

Scientists are especially interested in meteorites because they contain information about the solar system. It is widely believed by scientists that most meteorites are produced by collisions(碰撞) between asteroids (small planets). These collisions probably happened many billions of years ago. This means the physical and chemical structure of a meteorite can give scientists information about the early days of the universe.

1.The story is about ___.     

A.floods caused by meteors

B.matter from outer space

C.life on Earth millions of years ago

D.meteorites that have damaged the moon

2.The Earth has ___.                    

A.three billion craters

B.fewer craters than the moon

C.more craters than the moon

D.a(chǎn) thinner atmosphere than the moon

3.Some scientists believe the dinosaurs became extinct because ___.     

A.they were hit by meteors

B.meteorites landed on their nests

C.meteorites landed and changed the climate

D.they could no longer breathe the atmosphere

4.Meteors are ___.                                         

A.small planets

B.the same as asteroids

C.from broken parts of asteroids

D.the light we see when meteoroids hit our atmosphere

 

查看答案和解析>>

科目:高中英語 來源:2012-2013學年遼寧省五校協(xié)作體高三上學期期初聯(lián)考英語試卷(解析版) 題型:閱讀理解

Since ancient times, people have known about its ability to reduce pain and high body temperature. More than 2000 years ago, the Greek doctor Hippocrates advised his patients to chew on the bark and leaves of the willow.

    The tree contains a chemical called salicin(柳醇). From salicin, researchers in the 1800s discovered how to make salicylic acid(酸). And in 1897, a chemist named Felix Hoffmann at Friedrich Bayer and Company in Germany created acetyl salicylic acid. Later it became the active substance in a new medicine that Bayer called aspirin. The "a" came from acetyl. The "spir" came from the spirea plant, which also produces salicin. And the "in" Well, that is a common way to end medicine names.

In 1982, a British scientist shared the Nobel Prize in Medicine in part for discovering how aspirin works. Sir John Vane found that aspirin blocks the body from making natural substances called prostaglandins(前列腺素).Prostaglandins have several effects on the body. Some cause pain and the expansion, or swelling( 腫瘤; 膨脹), of damaged tissue. Others protect the lining of the stomach and small intestine. Prostaglandins also make the heart, kidneys and blood vessels (血管)work well. But there is a problem. Aspirin works against all prostaglandins, good and bad. Scientists learned how aspirin interferes with an enzyme(酶). One form of this enzyme makes the prostaglandin that causes pain and swelling. Another form of the enzyme creates a protective effect. So aspirin can reduce pain and swelling in damaged tissues. But it can also harm the inside of the stomach and small intestine(腸).

1.What sickness can the medicine from the willow deal with according to the passage?

A. Cold        B. Toothache         C. Cancer        D. Skin disease

2.What can we know about Prostaglandin according to the passage?

A. It results from pain.   

B. It prevents the lining of the stomach and small intestine.

C. It causes blood vessels to work wrongly.

D. It is sometimes good but sometimes bad.

3.What can we know about aspirin according to the passage?

A. Aspirin can treat almost diseases.

B. Aspirin can create the protective enzyme.

C. Aspirin can harm the inside of the stomach and small intestine.

D. Aspirin can protect the inside of the stomach and small intestine.

 

查看答案和解析>>

科目:高中英語 來源:重慶市09-10學年高一下學期第二次月考(英語) 題型:閱讀理解

The two largest islands of the British Isles are Great Britain and Ireland. England, Wales and Scotland together form Great Britain. Scotland, lying in the northern part of Great Britain and bordering(接壤)England on the south, is half the size of England and Wales, having an area of about 76 000 square kilometers. Most of Northern Scotland is mountainous area known as the Scottish Highlands. In the center of Scotland there are the Central Low-lands, and the south is waving, hilly area known as the Southern Uplands which rise to 800m. There are many rivers in Great Britain, but they are not very long. The rivers which run to the east are longer than the ones which run to the west.

In Scotland the main rainy winds come from the Atlantic Ocean. The west part is wet with an average(平均) rainfall of up to 200cm while the east is dry with about 75cm. The winters are cold with an average January temperature of 4℃. The summers are cold and warm but rarely hot.

1. This passage mainly tells us____ .

A. how many parts form Great Britain

B. the positions of England, Wales and Scotland

C. the areas of Great Britain

D. Something about Scotland

2. England lies____ .

A. in the south of Great Britain          B. to the south of Scotland

C. to the north of Wales                D. in the north of Scotland

3. This passage also tells us____ .

A. the population of Great Britain        B. the history of England and Wales

C. the size of Scotland                 D. the position of Northern Ireland

4. The Central lowlands_____ .

A. lie between the Scottish Highlands and the Southern Uplands

B. lie to the north of Scottish Highlands

C. lie to the south of the Southern Uplands

D. border England on the south

5. The writer says that in Scotland there is more rain____ .

A. in the Highlands than in the Southern Uplands     B. in the west part than in the east

C. in the Central Lowlands than in the Highland      D. in the east than in the west

 

查看答案和解析>>

科目:高中英語 來源:浙江省紹興市2010屆高三下學期教學質(zhì)量調(diào)測 題型:單項填空

17.---The weather repot says the temperature is going to drop sharply. Do remember to put on more clothes.

--- __________

A.Made it

B.Got it

C.Understood it

D.Heard it

 

查看答案和解析>>

同步練習冊答案