问题 问答题

小明同学为了研究一组材料的隔音性能(材料为:泡沫塑料扳、玻璃、木扳、硬纸扳)设计并做了一个实验,他们先把闹钟放人一只烧杯中,然后从听到最响的声音位置开始,慢慢远离声源,测得听不到指针走动声音时的位置与声间的距离.比较各种情况下这段距离的大小就可以比较不同材料的隔声性能.

进行实验收集到的数据为:

材料听不到闹钟指针走动

声音时的实际距离

泡沫塑料板0.3
玻璃0.6
木板0.4
硬纸板0.5
按隔音效果由好到坏依次排列:______、______、______、______.

总结好的隔音材料的共同特点之一是:______.

判断依据:______.

答案

由题意可知,如果距声源的距离越短说明材料的隔音性能更好,根据表格数据可知,泡沫塑料板的距离为0.3m最短,故隔音性能最好;木板的距离为0.4m,隔音效果次之,而硬纸板的距离是0.5m,隔音性能排在第三位,玻璃材料的距离为0.6m,隔音性能最差;

由几种材料对比可知,如果材料越松软,并且小孔越多,隔音性能越好.

故答案为:泡沫塑料板;木板;硬纸板;玻璃;松软多孔;吸音效果好.

阅读理解

阅读理解。   

     Mary is an American doctor. She is now in China. She works in a hospital in Hangzhou. She is also

learning Chinese medicine (医学) there. She likes Chinese medicine very much. She loves to work for

the patients (病人), because it's meaningful (有意义的). She works hard in the day and read English

books on Chinese medicine at night. She learns Chinese from Chinese doctors and her Chinese friends.

Now she can speak some Chinese. She can read some Chinese, too.

     Her husband (丈夫) John is a policeman. He works in a police station in Hangzhou, too. He works

hard, too. He's very busy. He works on Saturdays and Sundays. His work is kind of dangerous, but he s

ays, "I love my job very much. It's exciting and I can serve (服务) the people."

1. Mary and her husband are from _______.

A. America        

B. English      

C. China        

D. Australia

2. Mary loves her work, because _______.

A. it's busy

B. she can help the patients and her job is meaningful

C. she likes Chinese medicine

D. she can work in Hangzhou

3. Mary often reads books on ______.

A. Chinese history              

B. English medicine

C. English                    

D. Chinese medicine

4. -How is Mary's Chinese?  -_______.

A. She learns Chinese from Chinese books

B. She doesn't want to learn Chinese

C. She learns Chinese from others and can speak and read some Chinese now

D. She can speak some Chinese, but she can't read it.

5. Which of the following is wrong(错)?

A. John is busy.

B. John loves to work for people.

C. John needn't work on weekends.

D. John and his wife (妻子) work in the same (相同的) city.

单项选择题