试题与答案

(1)在做平抛实验的过程中,小球在竖直放置的坐标纸上留下三点痕迹,如图是小球做平

题型:实验题

题目:

(1)在做平抛实验的过程中,小球在竖直放置的坐标纸上留下三点痕迹,如图是小球做平抛运动的闪光照片,图中每个小方格的边长都是0.54cm,已知闪光频率是30Hz,那么重力加速度g=___________m/s2,小球的初速度是___________m/s,球过A点时的速率是___________m/s。(小数点后保留二位)

(2)如图a是研究小球在斜面上平抛运动的实验装置,每次将小球从弧型轨道同一位置静止释放,并逐渐改变斜面与水平地面之间的夹角θ,获得不同的射程x,最后作出了如图b所示的x-tanθ图象,g=10m/s2。则:由图b可知,小球在斜面顶端水平抛出时的初速度v0=___________。实验中发现θ超过60°后,小球将不会掉落在斜面上,则斜面的长度为___________。

答案:

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题型:阅读理解

阅读理解。

   Very old people do raise moral problems for almost everyone who comes in contact with them.

Their values-this can't be repeated too often-are not necessarily our values.    Physical   comfort,

cleanness and order are not necessarily the most important things. The social services  from time

to time find themselves faced with a flat with decaying food covered by small worms, and  an old

person lying alone in bed, taking no notice of the worms. But is it interfering(干涉) with  personal

freedom to insist that they go to live with some of their relatives so that they might be taken  better

care of? Some social workers, the ones who clear up the worms, think we are in danger of carrying

this concept of personal freedom to the point where serious risks are being taken with the health and

safety of the old.

   Indeed, the old can be easily hurt or harmed. The body is like a car, it needs more mechanical

maintenance(机械维修,保养) as it gets older. You can carry this comparison right through to the

provision of spare parts. But never forget that such operations are painful experiences, however

good the results will be. And at what point should you stop to treat the old body? Is it morally right

to try to push off death by seeking the development of drugs to excite the forgetful old mind and to

activate the old body, knowing that it is designed to die? You can't ask doctors or scientists to decide,

because so long as they can see the technical opportunities, they will feel bound to give them a try, on

the principle that while there's life, there's hope.

   When you talk to the old people, however, you are forced to the conclusion that whether age is happy

 or unpleasant depends less on money or on health than it does on your ability to have fun.

1. What does the passage mainly tell us?

A. The values are different between the old and the young.

B. The moral problems raised by old people.

C. The personal freedom for the old.

D. Old people's viewpoint on life.

2. We can know from the first paragraph that __________.

A. Very old people would like to live alone to have more personal freedom.

B. Very old people are able to keep their room clean.

C. Very old people like to live with their children.

D. Social services have nothing to do with very old people

3. According to the author, which of the following is right?

A. The older a person, the more care he needs.

B. Too much emphasis has been put on old people's values.

C. The human body can't be compared to a car.

D. It is easy to provide spare parts for old people.

4. The underlined word "it" in the last paragraph refers to "_________".

A. their money or their health

B. the conclusion you come to

C. your talk to the old people

D. whether age is happy or unpleasant

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