问题 选择题

如图所示的事例中,属于增大压强的是:

答案

答案:B

题目分析:A、书包带子做的宽一些,是在压力一定的情况下,通过增大受力面积,减小压强,不符合题意;

B、切苹果器的刀片做得较薄,是在压力一定的情况下,通过减小受力面积,增大压强,符合题意;

C、轨道铺在枕木上,是在压力一定的情况下,通过增大受力面积,减小压强,不符合题意;

D、好奇”号火星车模型轮子大而宽,是在压力一定的情况下,通过增大受力面积,减小压强,不符合题意.

故选B.

点评:与生活联系非常密切的物理题,在我们日常生活中经常需要根据实际情况来增大或减小压强,要学会学以致用,活学活用,这才是学习物理的真正意义.解答时,要注意使用控制变量法.

阅读理解

阅读理解。

     On January 15, a little girl from the Chinese mainland was on the subway in Hong Kong. She

was eating something. A local man told her not to do so. The girl's mother told him to mind his

own business. A quarrel started. Hong Kong Mass Transit Railway rules say people cannot eat

on the subway. The rules say the train will be filled with the smell of food. They say the smell will

attract mice to the train. These mice might chew the cables and cause safety problems for passengers.

People caught eating on the subway will be fined up to 2,000 Hong Kong dollars (1,625 yuan),

Xinhua reported. Signs clearly say "no eating" and the rule is often announced on the subway and in

stations. However, the girl and her parents say they did not notice this.

     This seemingly small event has started a debate on the Internet, Xinhua reported.

     A netizen named Zhu Hongying said some Chinese consider bad habits like talking loudly in public

places, spitting or jumping queues as small matters. They simply don't care because they think public

places are not their private homes. "This kind of thinking shows a lack of a sense of social morality,"

she pointed out.

     Many people agree. "The parents (of the girl) should have apologized for their mistake," Zhang

Nan, 15, a Senior 1 student at Diaotai High School, Shaanxi, said to Teens. "Quarreling after making

the mistake only makes the situation more embarrassing for them."

     Reports of Chinese people behaving badly at tourist sites at home and abroad are nothing new.

Such reports are affecting the way other countries see Chinese people. Some foreign airports put

up signs in Chinese telling Chinese people not to talk loudly and not to spit everywhere. Many

Chinese people find this embarrassing.

     All this shows that one of the secrets to a good journey is to learn about local customs and

taboos before you go.

1.The underlined word taboos probably means _________.

A. something you buy or keep to remind yourself of a place or an occasion

B. a group of people who have the power to make and change laws

C. a general agreement that does not allow people to do, use or talk about something

D. guidance offering information of local weather, accommodation and specialties

2.According to the debate on the net reported by Xinhua, Chinese manners___________.

A. are far from being poor

B. leave much to be desired

C. are only too easy to improve

D. are always to blame anywhere anytime

3.The passage wants to tell us that ___________.

A. When in Rome, do as the Romans do

B. Birds of a feather flock together

C. Misfortune may be an actual blessing

D. A real man never goes back on his words

单项选择题