Light travels at a speed which is about a million times faster than the speed of sound. You can get some idea of this difference by watching the start of a race. If you stand some distance(距离) away from the starter, you can see smoke from his gun before the sound reaches your ears.
This great speed of light produces some strange facts. Sunlight(太阳光) 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 reached you. The nearest star is so far away that the light that you can see from it tonight started to travel towards you four years ago at a speed of nearly 2 million km. per minute. In some cases, the light from one of tonight’s stars had started on its journey to you before you were born.
Thus, if we want to be honest, we can’t say, “The stars are shining tonight.” We have to say instead, “The stars look pretty. They were shining four years ago, but their light has only just reached the earth.”
1.Light speed is ______ sound speed.
A. as fast as
B. a million times slower than
C. about millions of times faster than
D. about a million times faster than
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 sound before you see the smoke
B. the sound does not travel as fast as light
C. the sound will reach you before the man fires
D. sound travels about a million times faster than light
3.Sunlight obviously(显然的) ______ than the light of the moon.
A. has to travel a greater distance
B. moves less quickly
C. travels much more quickly
D. is less powerful
4. The scientific way of saying "The stars are shining tonight" should be ______.
A. the stars have been shining all the time
B. the stars seen tonight will shine four years later
C. the stars were shining long ago but seen tonight
D. the starlight seen today could be seen four years ago
九年级英语阅读理解中等难度题
Light travels at a speed which is about a million times faster than the speed of sound. You can get some idea of this difference by watching the start of a race. If you stand some distance(距离) away from the starter, you can see smoke from his gun before the sound reaches your ears.
This great speed of light produces some strange facts. Sunlight(太阳光) 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 reached you. The nearest star is so far away that the light that you can see from it tonight started to travel towards you four years ago at a speed of nearly 2 million km. per minute. In some cases, the light from one of tonight’s stars had started on its journey to you before you were born.
Thus, if we want to be honest, we can’t say, “The stars are shining tonight.” We have to say instead, “The stars look pretty. They were shining four years ago, but their light has only just reached the earth.”
1.Light speed is ______ sound speed.
A. as fast as
B. a million times slower than
C. about millions of times faster than
D. about a million times faster than
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 sound before you see the smoke
B. the sound does not travel as fast as light
C. the sound will reach you before the man fires
D. sound travels about a million times faster than light
3.Sunlight obviously(显然的) ______ than the light of the moon.
A. has to travel a greater distance
B. moves less quickly
C. travels much more quickly
D. is less powerful
4. The scientific way of saying "The stars are shining tonight" should be ______.
A. the stars have been shining all the time
B. the stars seen tonight will shine four years later
C. the stars were shining long ago but seen tonight
D. the starlight seen today could be seen four years ago
九年级英语阅读理解中等难度题查看答案及解析
根据短文内容,用方框中所给词的适当形式填空,并用其正确形式填空,使短文完整,正确。(每个词只能用一次;共10分,每小题一分)
Light travels at a speed(速度) which is about a million times faster than that of sound .1.
________ One second, light travels about 300000 kilometers, but sound travels only 340 2.. You can get some idea of this difference by 3.________ the start of a running match. If you stand far away from the starter(发令员), you can see smoke4.________ from his gun before the sound reaches your ears.
The 5.________ speed of light produces some strange facts. The 6.________ star is so far away that light which you can see from it tonight started to travel to you four years 7.________ at a speed of nearly two million kilometers every minute. The light from some of tonight's started on8. ________ journey towards you even before you were born.
So, if we want to be honest(诚实), we can not say , " The stars are shining 9. ________tonight." We have to say, " The stars look nice. They were 10._______ four years ago but their light has just reached our earth. "
九年级英语选词填空中等难度题查看答案及解析
Spacecraft can travel ______the speed of light .
A. for B. on
C. in D. at
九年级英语单项填空中等难度题查看答案及解析
All languages change over time, but some change at a faster speed than others.1. One is about people who always use it. Another is about the importance of the language among different areas, such as world communication and changes in technology. In the past, other languages like Latin or French were more important than English. 2. English is spoken by about 350 million people as a first language in countries and about a billion more people as a second language.
English started to take the place of French as an international language during the period of British colonialism(殖民主义).3. The colonial period came to an end while some other changes happened. New ways of communication technology like television and the Internet make English worldwide.4.They could use the Internet for information, business, or e-mail in English. Just as the use of English spread, other languages changed English by new inventions and technology.
Icelandic(冰岛语)has changed very slowly. Why? Because Iceland is an island in the middle of the Atlantic Ocean.5. Today, most Icelanders speak English and Icelandic.
A. What are the reasons?
B. These changes influence the development of society.
C. People could watch news or programs in English everywhere.
D. English was the primary way to communicate in these colonies.
E. However, today English is the most widely used language in the world.
F. It meant Icelanders had little connect with speakers of other languages for many years.
九年级英语补全短文6选5中等难度题查看答案及解析
Millions of stars are travelling about in space. A few form groups which travel together, but most of them travel alone.
And they travel through a universe which is so large that one star seldom comes near to another. For the most important part each star makes its journey in complete loneliness, like a ship on an empty ocean. The ship will be well over a million miles from its nearest neighbour. From this it is easy to understand why a star seldom finds another anywhere near it.
We believe, however, that some two thousand million years ago, another star wandering(漫游) through space, happened to come near our sun just as the sun and the moon raised its tides(潮汐) on the earth, so this star must have raised tides on the surface of the sun. But they were very different from the small tides that are raised in our oceans; A large tidal(潮汐的) wave must have travelled over the surface of the sun, at last forming a mountain so high that we cannot imagine it. As the cause of the disturbance came nearer, so the mountain rose higher and higher. And before the star began to move away again, its tidal pull had become so powerful that this mountain was torn to pieces and thrown off small parts of itself into space.
These small pieces have been going round the sun ever since. They are the planets.
1.Most stars are _________________________.
A. following a regular path in space
B. moving about without a fixed course
C. seldom wandering about in the universe
D. always travelling together
2.Some two thousand years ago, the mountain on the sun was raised probably because _____________.
A. the star moved away from the sun
B. another star happened to come near the sun
C. the sun and the moon raised the tides on the earth
D. a large tidal of wave travelled over the surface of the sun
3.The article suggests that _______________.
A. how space formed
B. our earth exists before the sun
C. no one knows where the earth comes from
D. our earth used to be a high mountain in the sun
4.The expression “the cause of the disturbance” refers to ________.
A. the large tidal wave B. the powerful tidal pull
C. the star coming near the sun D. one of sun’s planets
5. In the article, the writer mainly wants to tell us ______________.
A. where the planets in the universe came from
B. how the high mountains were formed on the sun
C. that the universe is so large that we cannot imagine it
D. why the tides over the surface of the sun were so powerful
九年级英语阅读理解简单题查看答案及解析
Sound travels ______ air ______ a speed of about 340 metres per second.
A.over; in B.through; at C.by; at D.through; over
九年级英语单项填空中等难度题查看答案及解析
The teacher told us _________.
A. light travelled as fast as sound
B. light travelled faster than sound
C. light travels as fast as sound
D. light travels faster than sound
九年级英语单项填空中等难度题查看答案及解析
---Do you know sound travels very fast?
----Yes. But light travels _______ sound.
A. as fast as B. more faster than
C. much faster than D. slower than
九年级英语单项填空中等难度题查看答案及解析
—Do you know sound travels very fast?
—Yes. But light travels ________ sound.
A.as fast as B.a little faster than
C.much faster than D.slower than
九年级英语单选题中等难度题查看答案及解析
— Do you know sound travels very fast?
— Yes. But light travels ________ sound.
A.as fast as | B.a little faster than |
C.much faster than | D.slower than |
九年级英语单项填空中等难度题查看答案及解析