问题 填空题

(1)我国家庭电路的电压是________V,各个用电器之间的电路连接方式是_______联。

(2)工厂里的冷却塔大多用水作为冷却物质,是因为水的__________较大;在古代,人类学会了钻木取火的方法,这是将__________能转化为物体的内能。

答案

(1)220  并      (2)比热容  机械

题目分析:(1)我国家庭电路电压是220V.

家庭电路中各家用电器之间是并联的,这种连接方法,使各家用电器都能正常工作,并且互不影响.

(2)因为水的比热容较大,相同质量的水和其它物质比较,升高相同的温度,水吸收的热量多,所以常用水给汽车发动机降温;

在钻木取火中,即消耗机械能,产生内能,故属于做功改变物体的内能.

点评:家庭电路的电压和家用电器的额定电压是相同的.掌握各家用电器之间,开关和家用电器之间的连接方法.

水的比热容大的特点及应用、改变物体内能的方法的了解和掌握.

阅读理解

任务型阅读。请认真阅读下列短文,并根据所读内容在文章后表格中的空格里填入最恰当的单词。

注意:每空格1个单词。

     A mother, surnamed Wang, wondered why her daughter's junior middle school had not held a parents'

meeting over the course of two terms, so she phoned the school. The teacher told her the school had been

meeting with parents every month.

     Faced with her mother's discovery, the daughter, Ping Ping, a 13-year-old Grade-One middle school

student, admitted (承认) that she had hired the aunt of a classmate to play the role of her mother. She paid

the woman 50 yuan per meeting.

     Wang was very angry and slapped her daughter in the face.

     However, the girl appeared not to feel guilty (内疚) and stood her ground.

     "It is not my fault. Your bad behavior and dress style made me lose face," she said.

     Ping Ping complained that as far back as primary school, her mother had attended the parents' meeting

in the same black and white suit and acted as what the daughter described.

     When teachers invited parents to say a few words at the meeting, Wang often spoke with a very strong

local dialect (方言) while the other parents spoke fluent Mandarin and made brief speeches.

     Fearing that her mother would become a laughing stock (笑柄), Ping Ping decided to prevent her from

coming to parents' meeting.

     She hired her classmate's aunt to attend the parents' meeting in her mother's place.

     Mrs. Zhang, a psychologist, said it was common for young people to feel that other people's parents

were more attractive and educated than their own. The incident helps make people realize misunderstanding

can occur between parents and young children when they do not talk to one another. 

     "Teachers should help students understand the hardships parents face and organize more group activities

for parents and children," Zhang said. 

    "Parents also need to communicate with their children regularly and try to behave themselves to become

role models.

单项选择题