问题 问答题

试用一只塑料可乐瓶,一张硬纸片一根吸管等材料设计几个有关于压强的实验.(至少设计两个).

答案

答案不唯一,如:

实验一:在可乐瓶中装满水,并把瓶盖旋紧,找砂坑或找一海绵等软物,把装满水的可乐瓶正放和倒过来放,发现陷下去程度不同,可见在压力相同的情况下,压强大小与受力面积的大小有关.

实验二:在塑料瓶的侧壁不同高度处开三个小孔,再在可乐瓶中装满水时就可看到水从小孔中射出,离水面越远的小孔中的水射得越远.可见液体内部压强随深度增加而变大.

实验三:在可乐瓶中装满水,再用硬纸片盖在瓶口用手压住,把瓶翻转180°再把手指移开,水没流下来,是大气压托住了硬纸片,从中托住了水.

判断题
单项选择题

Passage Two

If there is one thing I’m sure about, it is that in a hundred years from now we will still be reading newspapers. It is not that newspapers are a necessity. Even now some people get most of their news from television or radio. Many buy a paper only on Saturday or Sunday. But for most people reading a newspaper has become a habit passed down from generation to generation.

The nature of what is news may change. What basically makes news is what affects our lives—the big political stories, the coverage of the wars, earthquakes and other disasters, will continue much the same. I think there will be more coverage of scientific research, though. It’s already happening in areas that may directly affect our lives, like genetic engineering. In the future, I think there will be more coverage of scientific explanations of why we feel as we do—as we develop a better understanding of how the brain operates and what our feelings really are.

It’s quite possible that in the next century newspapers will be transmitted electronically from Fleet Street and printed out in our own home. In fact, I’m pretty sure that how it will happen in the future. You will probably be able to choose from a menu, making up your own newspaper by picking out the things you want to read--sports and international news, etc.

I think people have got it wrong when they talk about competition between the different media. They actually feed off each other. Some people once foresaw that television would kill off newspapers, but that hasn’t happened. What is read on the printed page lasts longer than pictures on a screen or sound lost in the air. And as for the Internet, it’s never really pleasant to read something just on a screen.

From the passage,we can infer()·

A.newspapers will win the competition among the different media

B.newspapers will stay with US together with other media

C.television will take the place of newspaper

D.the writer believes some media will die out