Light travels at a speed which is about a million times faster than the speed of sound. In a second, light travels about 300,000km, but sound travels only 340m. You can get some ideas of this difference by watching the start of a race. If you stand some distance away from the starter, you can see smoke come from his gun before the sound reaches your ears.
This great speed of light produces some strange facts. Sunlight takes about 8 minutes to reach us. If you look at the light of the moon tonight, remember that the light rays left the moon 1.3 seconds before they reach you. The nearest star is so far away that the light which you can see from it tonight started to travel towards you four years ago at a speed of nearly 20 million km, per minute. In some cases, the light from one of tonight's stars started on its journey to you before you were born.
Thus, if we want to be honest, we can not say,
“the stars are shining tonight.”We have to say,“The stars look pretty. They were shining four years ago but their light has only just reached the earth.”阅读短文，选择最佳答案．
(1) The speed of light is ________ than the speed of sound.
[ ]
A
．a million times slowerB
．about millions of times fasterC
．about a million times faster(2) If you stand 200 meters away from a man who is firing a gun to start a race, you will find out that ________.
[ ]
A
．you can hear the gun before you see the smokeB
．sound doesn't travel as fast as lightC
．the sound of gun will reach you before the man fires his gun(3) Sunlight ________ to the earth than the light of the moon.
[ ]
A
．has to travel a greater distanceB
．moves less quicklyC
．is less powerful(4) The scientific way of saying
“the star are shining tonight”should be ________.[ ]
A
．the stars have been shining all the timeB
．the stars seen tonight will be shining four years laterC
．the stars were shining long ago but are seen tonight(5) The light of the nearest star you see tonight has been ________ for four years.
[ ]
|
A ．away from the star |
B ．on the moon |
C ．away from the sun |
科目：初中英语 来源： 题型：阅读理解
| 【小题1】 |
|
| 【小题2】 |
|
| 【小题3】 |
|
| 【小题4】 |
|
| 【小题5】 |
|
| 【小题6】 |
|
| 【小题7】 |
|
| 【小题8】 |
|
| 【小题9】 |
|
| 【小题10】 |
|
| 【小题11】 |
|
| 【小题12】 |
|
查看答案和解析>>
科目：初中英语 来源：2011届江苏省无锡市锡山区中考一模英语试卷 题型：阅读理解
The Bermuda Triangle(百慕大三角)is in the Atlantic Ocean, near Florida in the USA. During the past 60 years, more than 1,000 seamen in ships and pilots in planes have lost their lives. It is known as “The Triangle of Death”for its strange seawater and sudden storms. What’s the strangest is the light of the seawater, which looks so bright that it can be seen even from an outer spaceship.
At 2:00p.m. on Dec. 5, 1945, five planes took off in fine weather from the airport of Florida, on a training task. Two hours later, the leader in the sky radioed that he was “completely lost”. Then there was silence. Another plane was sent to look for them and also disappeared.
One of the largest ship that had disappeared in the triangle was an American coal ship, 500meters long. The weather was good, and there were no messages for help before it was “gone”. No broken ships or dead bodies have been found so far.
No one is able to tell how all these accidents have happened. A group of Japanese scientists were there to see what it was really like in 1995, but nothing has been heard of them ever since.
【小题1】 What is the passage mainly about?
| A．How the Bermuda Triangle ate up the planes and ships. |
| B．Why many of the planes and ships have disappeared. |
| C．Strange accidents happened in the Bermuda Triangle, no one can tell why |
| D．When the Bermuda Triangle was formed very strangely. |
| A．Five. | B．Six. | C．Seven. | D．Eight. |
| A．Wrote sound message using a radio. |
| B．Listened to sound message using a radio. |
| C．Sent sound message using a radio. |
| D．Received sound message using a radio. |
| A．He met with terrible weather. |
| B．He was losing the right direction. |
| C．Airport didn’t give him an answer. |
| D．The reasons are still unknown. |
| A．They have also disappeared very strangely. |
| B．They have not heard of anything important. |
| C．They are still working hard in Bermuda. |
| D．They’ve come back, knowing nothing about it. |
查看答案和解析>>
科目：初中英语 来源：2013-2014学年福建省九年级上学期期末考试英语试卷（解析版） 题型：阅读理解
阅读下面短文，把方框中的句子还原到文中，然后完成第五小题。（每题1分，共5 分）
If you look at the sky one night and see something moving and shining that you have never seen before, it might be a comet (彗星).
A comet sometimes looks like a star.? ____1.____ It shines from the sunlight it reflects (反射). Like the earth, a comet goes round the sun, but on a much longer path (轨道) than the earth travels.
??? If a comet isn’t a star, what is it then?
? Some scientists think that a large part of a comet is water frozen into pieces of ice and mixed with iron and rock dust and perhaps a few big pieces of rock. ____2.______ These clouds, together with the dust, form a long tail.
Many people perhaps have seen a comet. _____3._____ .There may be millions of comets, but only a few come close enough for us to see.
An Englishman named Edmund Halley, who lived from 1656 to 1742, found out a lot about the paths that comets take through the sky.? ______4.____? . Others keep coming back at regular times. A big comet that keeps coming back was named after Halley because he was the one who worked out when it would come back again. Maybe you have ever seen Halley’s Comets because the last time it came close to the sun and the earth was in the year 1986. Then people all over the world were outside at night to look at it. You will probably be able to see Halley’s Comets when it comes near the earth again.
A. However no one knows how many comets there are.
B. Some comets move out of our sight and never come
C. Like a planet, a comet has no light of its own.
D. When sunshine melts (融化) the ice in the comet, great clouds of gas go trailing after it.
5.Which of the following is not true?
A. A large part of a comet is ice, iron and rock dust
B. Some comets keep coming back at any time
C. Halley’s Comets came back in 1986
D. Maybe many people have seen a comet
查看答案和解析>>
科目：初中英语 来源：2012-2013学年安徽毫州风华中学九年级下期期末考试英语卷（解析版） 题型：阅读理解
When you look up into the sky at night, have you ever felt that your eyes are playing tricks on (捉弄) you? It seems that the stars are moving all the time.
Actually, there is nothing wrong with your eyes. This twinkling effect is called scintillation (交光). Scintillation happens because of air movements in the earth’s atmosphere (大气). Light is “bent (弯曲的)” when it travels through different parts of the earth’s atmosphere. As the air in the earth’s atmosphere is moving all the time, the light from the stars looks as if it is moving too.
The same thing also happens to things on the ground. On a very hot and shiny day, if you look at the road, the image in the distance is not clear and things move slightly. You can also see the same effect if you drop a rock into water. The rock appears a little unclear under the moving water.
This twinkling effect causes a lot of problems for astronomers (天文学家) since they cannot observe the stars clearly. A telescope (望远镜) was sent into space so that the air movements in the atmosphere could be avoided (避免). It took a long time to build the space telescope but finally in 1990, a huge space telescope called the Hubble Space Telescope was successfully sent into space. Since then, astronomers have many important observations that have helped people understand space better.
根据短文内容，选择最佳选项。 （10分）
1.What happens to the light from the stars we see when the air in the earth’s atmosphere is moving?
A．It looks even brighter.
B．It looks as if it is bent.
C．It looks as if it is moving.
D．It looks like drops of rain.
2.Scintillation also happens on according to the passage.
A．rainy days B．shiny days
C．cloudy days D．windy days
3.What can you see when you drop a rock into the water?
A．The rock gets broken.
B．The rock becomes unclear.
C．The water becomes much polluted.
D．The water does not move anymore.
4.The underlined word “observe” means “ ”.
A．watch B．listen C．draw D．explain
5.Why is scintillation a problem for astronomers?
A．The stars never stay still.
B．It makes the stars too dark to see.
C．It makes astronomers feel too hot to work.
D．Astronomers cannot observe the stars clearly.
查看答案和解析>>
科目：初中英语 来源：2011年河南省中考英语试卷 题型：阅读理解
What do you do if you're stranded（处于困境的）on a lonely island? Surely you need to find a way to get in touch with the outside world. Your best chance of doing this is to draw the attention of a passing plane.
Body signals（信号）
Pilots from different countries understand body signals if they have the correct training. When you wave your arms up and down in a straight line, it means "yes". When you point downwards and swing your arm from side to side, it means "no". If you want the pilot to know that it's safe to land, push your hands out in front of you and bend（弯曲）your knees. If you want to say that it's not safe to land, put your arms in the air and move them to one side.
Smoke signals
The smoke from a fire can be seen from far away, so it's a good way to draw attention. If the weather is dry, it isn't hard to start a fire. Remember, however, that fires can be very dangerous if they get out of control. Never light a fire unless you're sure that it can't spread. If the ground is dark, light smoke can be seen more easily. Green grass and leaves produce light smoke.
Ground-to-air signals
It's a good idea to build some signals, too. Use large pieces of wood to make the symbols(标记). If you can't find any wood, use earth. Some useful symbols are:
F "I need food and water."
II "I need medicine."
I "I am badly hurt."
X" I am unable to move from here."
Pilots' replies
If the pilot lowers the plane's wings from side to side, this means "message received and understood". (At night, the pilot flashes the plane's green lights.) If the pilots flies the plane in a clockwise circle, this means "message received but not understood".(At night, the pilot flashes the plane's red lights.)
However, there is no signal which means "message not received". Why not?
1. Which picture means "it's not safe land"?
2. What can we learn from the passage?
A. Swinging your arm from side to side means "yes".
B. If the ground is dark, light smoke can't be seen.
C. If you need some medicine, make a symbol "II".
D. The pilots make replies with a blue light at night.
3. What is the passage mainly about?
A. The explanation of building signals on an island.
B. The importance of making signals on an island.
C. Ways of sending out signals on a lonely island.
D. Ways of receiving signals from a lonely island
查看答案和解析>>
湖北省互联网违法和不良信息举报平台 | 网上有害信息举报专区 | 电信诈骗举报专区 | 涉历史虚无主义有害信息举报专区 | 涉企侵权举报专区
违法和不良信息举报电话：027-86699610 举报邮箱：58377363@163.com
