问题 不定项选择

2008年9月我国成功实施了“神舟七号”载人航天飞行并首次实现了航天员出舱。飞船先沿椭圆轨道1飞行,后在远地点343 km处的P点加速,由椭圆轨道1变成高度为343 km的圆轨道2,在此圆轨道2上飞船运行周期约为90 min,下列判断正确的是

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A.飞船在圆轨道上运行时航天员出舱前后都是处于失重状态

B.飞船在此圆轨道上运行的线速度大于同步卫星运动的线速度

C.飞船变轨前后通过椭圆轨道远地点P时的加速度相等

D.飞船变轨前的机械能大于变轨后的机械能

答案

ABC

阅读理解

阅读理解。

     Fashion is moving into the twenty-first century. A coat can change its color with the weather; a shirt

with stripes (条纹) that will disappear while you are wearing it; a blouse can be worn for days and days

without a bad smell... These are not dreams of scientists. They were made possible in the fashion world.

     A jacket changes its color in warm weather and costs between $ 40 and $ 5, 000. Peter White, a designer,

says "There are not much more designers can do with the old cloth. They need to make new kinds of cloth to

keep fashion interesting."

     Massimo Osti is the man who has brought this unusual cloth to the shops. Another of Osti's inventions

has a design of the company's trademark (商标) on the chest, which disappears when you breathe on it. Now

there is a special kind of leisure wear (休闲服) for golfers who like to practice in any kind of weather. As

golfers leave the warm club house, their clothes will change from white to rainbow (彩虹) of colors.

     A Japanese company has developed a man-made fiber (纤维), it can absorb (吸收) sunlight and keep the

wearer up to 10 ℃ warmer than usual fibers. A kind of new cloth for ski-wear can turn black to absorb

sunlight when the temperature drops to below zero, and change to white at above 5 ℃.

      In the Far East and Europe, there are many blouses which have a pleasing smell. The sweet smell lasts

up to three hand-washes.

1. What does the word "Fashion" mean in Chinese?

A. 食物

B. 饮料

C. 时装

2. Massimo Osti is _________.

A. a worker

B. a doctor

C. an inventor

3. When golfers go into the warm house, their special leisure wear will change from _________ to _________.

A. white... colorful

B. colorful... white

C. white... black

4. A man-made fiber can keep the wearer up to _________ warmer than usual one.

A. 10℃

B. 5 ℃

C. 0℃

5. Which of the following is NQT TRUE?

A. New kinds of cloth can keep the fashion world interesting.

B. All kinds of cloth can change their colors when the temperature changes.

C. Many blouses have a sweet smell which lasts up to three hand-washes in Europe.

选择题