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    The speed of Wave 1 is 100 cm/s, frequency 10. The frequency of Wave 2 is 300, while its speed is twice that of Wave 1. Which of the following is right? A. The wavelengths of the two are equal. B. The wavelength of Wave 1 is 10 times longer than that of Wave 2. C. The wavelength of Wave 2 is longer than that of Wave 1. D. The wavelength of Wave 1 is longer than that of Wave 2. Last summer I went through a training program and became a literacy volunteer. The training I received, though excellent, did not tell me how it was to work with a real student, however. When I began to discover what other people’s lives were like because they could not read, I realized the true importance of reading. My first student Marie was a 44-year-old single mother of three. In the first lesson, I found out she walked two miles to the nearest supermarket twice a week because she didn’t know which bus to take. When I told her I would get her a bus schedule, she told me it would not help because she could not read it. She said she also had difficulty once she got to the supermarket because she couldn’t always remember what she needed. Since she did not know words, she could not write out a shopping list. Also, she could only recognize items by sight, so if the product had a different label, she would not recognize it as the product she wanted. As we worked together, learning how to read built Marie’s self-confidence, which encouraged her to continue in her studies. She began to make rapid progress and was even able to take the bus to the supermarket. After this successful trip, she reported how self-confident she felt. At the end of the program, she began helping her youngest son, Tony, a shy first grader, with his reading. She sat with him before he went to sleep and together they would read bedtime stories. When his eyes became wide with excitement as she read, pride was written all over her face, and she began to see how her own hard work in learning to read paid off. As she described this experience, I was proud of myself as well. I found that helping Marie to build her self-confidence was more rewarding than anything I had ever done before. As a literacy volunteer, I learned a great deal about teaching and helping others. In fact, I may have learned more from the experience than Marie did. 【查看更多】

     

    题目列表(包括答案和解析)

     

     

     

    Wind is the great maker of waves. There are exceptions, such as the tidal waves, sometimes produces by earthquakes under the sea. But the waves most of us know are produced by winds blowing over the sea.?Now before constructing an imaginary life history of a typical wave, we need to know certain physical things about it. A wave has height, from trough (low point)to crest (high point),and it has length—the distance from this crest to that of the following wave. The period of the wave means the time it takes for succeeding crests to pass a fixed point. None of these things stays the same— for all depend upon the depth of the water and many other matters.?

    The water that makes up a wave does not advance with it across the sea. Each drop of water turns around in a little circle with the passing of the wave, but returns very nearly to its original position. And it is fortunate that this is so, for if the huge masses of water that make up a wave actually moved across the sea, sailing would be impossible.

    If we want to find the speed of a wave, we may use the following way:

    Speeding=Wavelength×Frequency

    Here, wavelength is the distance between two high points (crests), frequency means the number of cycles per second.?

    41.What causes waves according to the passage??

    Earthquakes and nothing else.   B. Wind and volcanos.

    C. Wind and earthquakes.          D. Wind and water.

    42.Which of the following is true according to the text??

    A. The water of a wave moves away across the sea.?

    B. The water of a wave remains almost in the same place.?

    C. The water of a wave goes with the passing of the wave.?

    D. The length of a wave means the distance between crest and trough.

    43.The underlined word “succeeding” means__________.?

    A. reaching an aim    B. doing well?  C. following after   D. taking place

    44.If the speed of wave 1 is 100 cm/s, and its frequency 10;and the frequency of wave 2 is 300,while its speed is twice that of wave 1.Which of the following is true??

    A. The wave-lengths of the two are equal.?

    B. The wave-length of wave 1 is 10 times longer than that of Wave 2.?

    C. The wave-length of wave 2 is longer than that of wave 1.?

    D. The wave-length of wave 1 is longer than that of wave 2.?

     

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    Wind is the great maker of waves. There are exceptions, such as the tidal waves, sometimes produces by earthquakes under the sea. But the waves most of us know are produced by winds blowing over the sea.?Now before constructing an imaginary life history of a typical wave, we need to know certain physical things about it. A wave has height, from trough (low point)to crest (high point),and it has length—the distance from this crest to that of the following wave. The period of the wave means the time it takes for succeeding crests to pass a fixed point. None of these things stays the same— for all depend upon the depth of the water and many other matters.?

    The water that makes up a wave does not advance with it across the sea. Each drop of water turns around in a little circle with the passing of the wave, but returns very nearly to its original position. And it is fortunate that this is so, for if the huge masses of water that make up a wave actually moved across the sea, sailing would be impossible.

    If we want to find the speed of a wave, we may use the following way:

    Speeding=Wavelength×Frequency

    Here, wavelength is the distance between two high points (crests), frequency means the number of cycles per second.?

    41.What causes waves according to the passage??

    Earthquakes and nothing else.   B. Wind and volcanos.

    C. Wind and earthquakes.          D. Wind and water.

    42.Which of the following is true according to the text??

    A. The water of a wave moves away across the sea.?

    B. The water of a wave remains almost in the same place.?

    C. The water of a wave goes with the passing of the wave.?

    D. The length of a wave means the distance between crest and trough.

    43.The underlined word “succeeding” means__________.?

    A. reaching an aim    B. doing well?  C. following after   D. taking place

    44.If the speed of wave 1 is 100 cm/s, and its frequency 10;and the frequency of wave 2 is 300,while its speed is twice that of wave 1.Which of the following is true??

    A. The wave-lengths of the two are equal.?

    B. The wave-length of wave 1 is 10 times longer than that of Wave 2.?

    C. The wave-length of wave 2 is longer than that of wave 1.?

    D. The wave-length of wave 1 is longer than that of wave 2.?

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    Wind is the great maker of waves. There are exceptions, such as the tidal waves, sometimes produces by earthquakes under the sea. But the waves most of us know are produced by winds blowing over the sea.?Now before constructing an imaginary life history of a typical wave, we need to know certain physical things about it. A wave has height, from trough (low point)to crest (high point),and it has length—the distance from this crest to that of the following wave. The period of the wave means the time it takes for succeeding crests to pass a fixed point. None of these things stays the same— for all depend upon the depth of the water and many other matters.?

    The water that makes up a wave does not advance with it across the sea. Each drop of water turns around in a little circle with the passing of the wave, but returns very nearly to its original position. And it is fortunate that this is so, for if the huge masses of water that make up a wave actually moved across the sea, sailing would be impossible.

    If we want to find the speed of a wave, we may use the following way:

    Speeding=Wavelength×Frequency

    Here, wavelength is the distance between two high points (crests), frequency means the number of cycles per second.?

    41.What causes waves according to the passage??

    Earthquakes and nothing else.   B. Wind and volcanos.

    C. Wind and earthquakes.          D. Wind and water.

    42.Which of the following is true according to the text??

    A. The water of a wave moves away across the sea.?

    B. The water of a wave remains almost in the same place.?

    C. The water of a wave goes with the passing of the wave.?

    D. The length of a wave means the distance between crest and trough.

    43.The underlined word “succeeding” means__________.?

    A. reaching an aim    B. doing well?  C. following after   D. taking place

    44.If the speed of wave 1 is 100 cm/s, and its frequency 10;and the frequency of wave 2 is 300,while its speed is twice that of wave 1.Which of the following is true??

    A. The wave-lengths of the two are equal.?

    B. The wave-length of wave 1 is 10 times longer than that of Wave 2.?

    C. The wave-length of wave 2 is longer than that of wave 1.?

    D. The wave-length of wave 1 is longer than that of wave 2.?

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    Wind is the great maker of waves. There are exceptions, such as the tidal(潮汐的) waves some??times produced by earthquakes under the sea. But the waves most of us know are produced by winds blowing over the sea.

    Now before constructing an imaginary life history of a typical wave, we need to know certain physical things about it. A wave has height, from trough (low point) to crest (high Point). It has length－the distance from this crest to that of the following wave. The period of the wave means the time it takes for succeeding crests to pass a fixed point. None of these things stays the same－for all depend upon the wind, upon the depth of the water and many other matters.

    The water that makes up a wave does not advance with it across the sea. Each drop of water turns around in a little circle with the passing of the wave, but returns very nearly to its original position. And it is fortunate that this is so. For if the huge masses of water that make up a wave actually moved across the sea, sailing would be impossible.

    If we want to find the speed of a wave, we may use the following way:

    Speed = wavelength × frequency

    Here, wavelength is the distance between two high points (crests), frequency means the number of cycles per second.

    What causes waves?

    A. Earthquakes and nothing else.         B. Only wind.

    C. Wind causes most waves.                D. Wind causes some waves.

    Which of the following is true according to the passage?

    A. The water of a wave moves away across the sea.

    B. The water of a wave remains almost at the same place.

    C. The water of a wave goes with the passing of the wave.

    D. The length of a wave means the distance from the top of a wave to the bottom.

    The speed of Wave 1 is 100 cm/s, frequency 10. The frequency of Wave 2 is 300, while its speed is twice that of Wave 1. Which of the following is right?

    A. The wavelengths of the two are equal.

    B. The wavelength of Wave 1 is 10 times longer than that of Wave 2.

    C. The wavelength of Wave 2 is longer than that of Wave 1.

    D. The wavelength of Wave 1 is longer than that of Wave 2.

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    Wind is the great maker of waves. There are exceptions, such as the tidal waves, sometimes produces by earthquakes under the sea. But the waves most of us know are produced by winds blowing over the sea.?Now before constructing an imaginary life history of a typical wave, we need to know certain physical things about it. A wave has height, from trough (low point)to crest (high point),and it has length—the distance from this crest to that of the following wave. The period of the wave means the time it takes for succeeding crests to pass a fixed point. None of these things stays the same— for all depend upon the depth of the water and many other matters.?

    The water that makes up a wave does not advance with it across the sea. Each drop of water turns around in a little circle with the passing of the wave, but returns very nearly to its original position. And it is fortunate that this is so, for if the huge masses of water that make up a wave actually moved across the sea, sailing would be impossible.

    If we want to find the speed of a wave, we may use the following way:

    Speeding=Wavelength×Frequency

    Here, wavelength is the distance between two high points (crests), frequency means the number of cycles per second.?

    1.What causes waves according to the passage??

    A.   Earthquakes and nothing else.   B. Wind and volcanos.

    C. Wind and earthquakes.          D. Wind and water.

    2.Which of the following is true according to the text??

    A. The water of a wave moves away across the sea.?

    B. The water of a wave remains almost in the same place.?

    C. The water of a wave goes with the passing of the wave.?

    D. The length of a wave means the distance between crest and trough.

    3.The underlined word “succeeding” means__________.?

    A. reaching an aim    B. doing well?  C. following after   D. taking place

    4.If the speed of wave 1 is 100 cm/s, and its frequency 10;and the frequency of wave 2 is 300,while its speed is twice that of wave 1.Which of the following is true??

    A. The wave-lengths of the two are equal.?

    B. The wave-length of wave 1 is 10 times longer than that of Wave 2.?

    C. The wave-length of wave 2 is longer than that of wave 1.?

    D. The wave-length of wave 1 is longer than that of wave 2.?

     

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