试题与答案

一个熟透的苹果从树上掉下来，在下落过程中（ ） A．苹果的重力势能保持不变 B．

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题型：选择题

题目：

一个熟透的苹果从树上掉下来，在下落过程中  （　　）

A．苹果的重力势能保持不变

B．苹果的重力势能越来越大

C．苹果的动能越来越大

D．苹果的动能越来越小

答案：

苹果下落过程，高度减小，所以重力势能减小，故A、B不正确；

苹果在下落过程，重力势能转化为动能，所以苹果的动能越来越大，故D不正确，C正确；

故选C．

考点：动能和势能的应用
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题型：阅读理解

Cold weather has a great effect, on how our minds and our bodies work. Maybe that is why there are so many expressions that use the word “cold”. For centuries, the body’s blood has been linked closely with the emotions. People who show no human emotions or feelings, for example, are said to be cold-blooded. Cold-blood people act in a merciless way. They may do brutal things to others, and not by accident. For example, a newspaper says the police are searching for a cold-blooded killer. The killer murdered someone, not in self-defense. He seemed to kill with no emotion.

Cold can affect other parts of the body, the feet, for example. Heavy socks can warm your feet, if your feet are really cold. But there is an expression ---- to get cold feet--- that has nothing to do with cold or your feet. The expression means being afraid to do something you decided to do. For example, you agree to be president of an organization. But then you learn that all the other officers have resigned. All the work of the organization will be your responsibility. You are likely to get cold feet about being president when you understand the situation.

Cold can also affect your shoulder. You “give someone the cold shoulder” when you refuse to speak to them. You treat them in a distant, cold way. The expression probably come from the physical act of turning your back toward someone, instead of speaking to him face-to- face. You may give a cold shoulder to a friend who has not kept a promise he made to you or to someone who has lied about you to others.

“A cold fish” is not a fish. It is a person. But it is a person who is unfriendly, unemotional and show no love or warmth. A cold fish does not offer much of himself to anyone.

“Out in the cold” is and expression often heard. It means not getting something that everybody else got. A person might say that everybody but him got a pay raise. He was left our in the cold. And it is not a pleasant place to be.

小题1: The text is intended to tell us that ______.

A．cold weather has a great effect on human bodies

B．“cold” is a word closely linked with human emotions

C．many English expressions contain the word “cold”

D．the word “cold” has many different meanings in English小题2:The underline word “brutal” in paragraph 1 most probably means ______.

A．merciless

B．illegal

C．impolite

D．extreme小题3:Which phrase can best describe a person who is unwilling to offer anything to others?

A．Cold-blooded.

B．To get cold shoulder.

C．A cold fish.

D．A cold shoulder.小题4:If the teacher gives all the boys except Tom a pen as a prize, you can say he ______.

A．is given the cold shoulder

B．is punished by a cold fish

C．has got cold feet

D．is left out in the cold
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