To fight a noise by making more noise sounds strange ,but that's exactly what motor engine - 试题答案网问答

第1题

According to the passage, which of the following is fight？A．The writer's teacher was very

According to the passage, which of the following is fight？

A．The writer's teacher was very strict.

B．The writer was very clever.

C．The writer got to school early that morning.

D．The writer got to his desk in the noise without being seen.

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第2题

D To fight a noise by making more noise sounds strange, but that ' s exactly what motor e

D

To fight a noise by making more noise sounds strange, but that ' s exactly what motor engi-

neers are doing in Germany and some other countries.

Carmaker ' s research and development laboratories have already proved that mixing more noise

with the help of loudspeakers can reduce the unwanted noise. Physicists have known about the tech-

nique for a long time. Sound is made up of pressure waves in the air. If two sound waves' of the

same frequency(频率） mix so that the highest point of one wave happens at the same time as the'

lowest point of the other wave, the result is no sound. Therefore, by producing a perfect copy of

the noise and delaying it by half a wave cycle(周期) ,we can kill the unwanted noise. Using this

technique many carmakers are racing to develop noise killing systems(系统) borh inside and outside

the cars.

Another good thing about the use of noise killing systems is that it saves the need for a silencer; this not only reduces the weight of a car, but also makes the motor bum less fuel and work better. Sorpe engineers believe that the noise killing system will be used in most cars within a few

years. But the carmakers haven' t decided if they will carry it into production because it would add several hundred dollars to the cost of their cars.

69. Which of the following gives a general idea of how the noise killing system works？

[ A]By producing pressure waves going in the opposite direction.

[ B ] By mixing high frequency sound waves with .low frequency sound waves.

[C]By mixing new sound waves with the noise and sending them out together.

[D]By making copies of the unwanted sound waves and letting them out a little later.

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第3题

To fight a noise by making more noise sounds strange, but that's exactly what motor engine

ers are doing in Germany and some other countries.

Car makers' research and development laboratories have already proved that mixing more noise with the help of loudspeakers can reduce the unwanted noise.

Physicists have known about the technique for a long time. Sound is made up of pressure waves in the air. If two sound waves of the same frequency (频率) mix so that the highest point of one wave happens at the same time as the lowest point of the other wave, the result is no sound. Therefore, by producing a perfect copy of the noise and delaying it by half a wave cycle (周期), we can kill the unwanted noise. Using this technique many carmakers are racing to develop noise-killing systems (系统) both inside and outside the cars.

Another good thing about the use of noise-killing systems is that it saves the need for a silencer; this not only reduces the weight of a car, but also makes the motor burn less fuel and work better.

Some engineers believe that the noise-killing system will be used in most cars within a few years. But the carmakers haven't decided if they will carry it into production because it would add several hundred dollars to the cost of their cars.

Which of the following gives a general idea of how the noise-killing system works？

A．By producing pressure waves going in the opposite direction.

B．By mixing high frequency sound waves with low frequency sound waves.

C．By mixing new sound waves with the noise and sending them out together.

D．By making copies of the unwanted sound waves and letting them out a little later.

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第4题

When a new movement in art attains a certain fashion, it is advisable to find out what its

advocates are aiming at, for, however farfetched and unreasonable their principles may seem today, it is possible that in years to come they may be regarded as normal. With regard to Futurist poetry, however, the case is rather difficult, for whatever Futurist poetry may be even admitting that the theory on which it is based may be right, it can hardly be classed as Literature.

This ,in brief, is what the Futurist says ;for a noise and violence and speed. Consequently, our feelings, thoughts and emotions have undergone a corresponding change. This speeding up of life, says the Futurist, requires a new form. of expression. We must speed up our literature too, if we want to interpret modem stress. We must pour out a large stream of essential words, unhampered by stops, or qualifying adjectives, of finite verbs. Instead of describing sounds we must make up words that imitate them; we must use many sizes of type and different colored inks on the same page, and shorten or lengthen words at will.

Certainly their descriptions of battles are confused. But it is a little upsetting to read in the explanatory notes that a certain line describes a fight between a Turkish and a Bulgarian officer on a bridge off which they both fall into the river and then to find that the line consists of the noise of their falling and the weights of the officers: Huff! Huff! A hundred and eighty-five kilograms. This, though it fulfills the laws and requirements of Futurist poetry, can hardly be classed as Literature. All the same, no thinking man can refuse to accept their first proposition: that a great change in our emotional life calls for a change of expression. The whole question is really this: have we essentially changed？

This passage is mainly______.

A．a survey of new approaches to art

B．a review of Futurist poetry

C．about merits of the Futurist movement

D．about laws and requirements of literature

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第5题

①noise / ②What’s / ③that / ④（）

A.②③①④

B.①③②④

C.②①③④

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