下列说法正确的是 ( )
A．热量不能由低温物体传递到高温物体
B．外界对物体做功，物体的内能必定增加
C．第二类永动机不可能制成，是因为违反了能量守恒定律
D．不可能从单一热源吸收热量并把它全部用来做功，而不引起其他变化
答案：D
【错解分析】AC 没有全面正确地理解热力学第二定律．
【正解】热量不能自发地由低温物体传递给高温物体，故A不对；据热力学第一定律，△U=W+Q，W为正，而吸热或放热未知，故AU不确定，B不对；第二类永动机符合能量守恒定律，但违反了内能与机械能转化的方向性，故C不对．效率是100％的热机不可能制成，任何宏观热现象都具有方向性，故D对．
| Reading newspapers has become an important part of everyday life. Some people read newspapers as the first thing to do in the morning, others read newspapers as soon as they have free time during the day so that they can learn what is happening in the world. Sometimes, we do not have enough time to read all the news carefully, so we just take a quick look at the front page. At other times, we may be in such a hurry that we only have a few minutes to look at the headlines (标题) of the passage. Newspapers can be found everywhere in the world. We can get many different kinds of newspapers in big cities, but in some mountain villages we can see few newspapers. Some newspapers are published (出版) once a week, but most of the papers are published once a day with many pages, some even published twice a day! You know different people enjoy reading different newspapers. Some like world news, and others prefer short stories. They just choose what they are interested in. Today newspapers in English have the largest numbers of readers in the world, The English language is so popular that many Chinese students are reading English newspapers such as China Daily or 21st Century. Also they bring us more and more information with internet. |
| 1. People read newspapers in order to . |
[ ] |
| A. learn the latest news B. meet their own different needs C. read the short stories D. find the morning news |
| 2. From the passage we can see that when people get newspapers. |
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| A. they read them very carefully B. they just read the headlines C. not everyone reads all the pages D. they have no time to read them |
| 3. According to the passage, besides newspapers, people also get information from . |
[ ] |
| A. magazines B. advertisements C. e-mails D. internet |