题目

要使“110 V  40 W”（L1）和“110 V 100 W”（L2）的两种灯泡接在220V的电路中都能正常发光，则可采用的接法是图14-4-6中的（图中R值可适当选择）_________，能正常发光的电路中________耗电量最小. 图14-4-6 答案：解析：A电路是对称的，先串后并，电压平分，能正常发光，PA=280W.B电路中因I2大于I1，能正常发光，PB=200 W.C电路中两灯不能同时正常发光.D能正常发光，PD=280 W. 答案：ABD    B 第一节 听下面5段对话或独白。每段对话或独白后有几个小题，从小题中所给的A、B、C三个选项中选出最佳选项，并将答案涂在答题卡上标号为1－15的相应位置。听每段对话或独白前，你将有时间阅读各个小题，每小题5秒钟；听完后，各个小题将给出5秒钟的作答时间。每段对话或独白读两遍。 听第1段材料，回答1－3题。 1．What will they put on a show for？ A．For money． B．For fun． C．For fame． 2．What will they perform in the show？ A．Three popular songs． B．A musical play． C．Three pieces of music． 3．What will the man do in the show？ A．He’ll sing church songs． B．He will act as stage director． C．He’ll sing and dance． 听第2段材料，回答第4－6题。 4．How did the woman get into touch with her family？ A．By letter． B．By computer． C．By telephone． 5．What does the man suggest the woman doing？ A．Learning how to use internet． B．Talking with people on line． C．Making friends in the discussion group． 6．What is the man most interested in？ A．Discussing problems． B．Music． C．Word processing． 听第3段材料，回答第7－9题。 7．What is the man？ A．A bus driver． B．A manager in a bus company． C．A reporter． 8．What is the woman’s opinion about the bus service？ A．There are too many stops． B．The time-tables are not accepted． C．Buses are often not on time． 9．Why does the woman say her husband is fortunate？ A．He often goes to work in a friend’s car． B．He doesn’t need to go shopping by bus． C．He works in a bus station． 听第4段材料，回答第10－12题。 10．What is not mentioned about the woman’s work？ A．Visiting friends． B．Taking a dog for a walk． C．Bathing the baby． 11．What does the dialogue mainly express？ A．Housewives'need for a change in their life． B．Housewives'need for proper jobs． C．Men’s dissatisfaction with their wives． 12．What can we learn from the dialogue？ A．The woman does not want her husband to go out and work． B．The husband does not understand his wife’s feelings． C．The husband does not care for his wife very much． 听第5段材料，回答第13－15题。 13．What does“collide”mean？ A．Hit each other hard． B．Stop． C．Run a race with each other． 14．What was true when the first car accident happened？ A．People had seen a lot of cars． B．People were already used to cars． C．The car had had only a short history． 15．Which of the following is not true？ A．The bike rider did not die． B．The bike rider was from Massachusetts． C．A car was going by when Mr．Bliss got out of the street car． 第二节：听取信息 听下面一段对话。请根据题目要求，从所给的内容中获取必要的信息，填入答题卷标号为16－20的空格中。录音读两遍。你有90秒钟的作答时间。 完成以上表格，每空不超过3个单词。