问题 问答题 简答题

简述配热电偶用动圈式温度表的工作原理?

答案

参考答案:

配热电偶用动圈式温度表的工作原理:热电偶产生的热点势输入仪表后,测量回路中将有电流流过,产生磁场,该磁场与永久磁铁的磁场相互作用,使动圈受力产生旋转力矩,使动圈和指针发生转动,随着动圈偏转,张丝产生弹性扭变,张丝对动圈产生反作用力矩。当旋转力矩与反作用力矩平衡时,动圈的转动就停止了,指针就停留在刻度盘的某一位置上,这样就可以测量出温度值。

单项选择题 A1/A2型题
阅读理解

Few students would dream of getting a job as a shoe shiner working along the street. College students, in their own eyes and in the eyes of the public, are expected to get at least a proper job, if not working in a high-income or white-collar position.

Cai Yong’s decision to work as a shoe shiner shocked not only his parents, who had high hopes for him, but also his girlfriend.

“It is right for young graduates to be ambitious (有抱负的). But they have to start in a solid

and down-to-earth way,” Cai said. Cai is not alone in making such a choice. The company has got

12 college students in all.

“I come for the 800 yuan monthly pay,” said Xiao Ji, who is a student from Nanjing University. “I have grown up and no longer live on my parents,” he said.

“Working as shoe shiners can mean a bright future,” Cai said.

Not everyone can accept this job choice. Cai’s girlfriend left him because she felt ashamed to be with a shoe shiner, and Cai accepted the fact. “This is the price to be paid for a job,” he said.

A former shoe shiner, Zhong Haibo, from a medical college, believes it was a good training for the rest of his life. “There is nothing I can’t do after working as a shoe shiner,” Zhong said, meaning that such kind of experience in early life is helpful in a future job.

39. Cai Yong decided to work as          .

A. a college teacher  B. a company manager  C. a shoe shiner   D. a medicine maker

40. Why did Cai’s girlfriend leave him?  

A. They didn’t get along well with each other.   B. Her parents didn’t like him.

C. She found it a shame to marry a shoe shiner.  D. Cai had got a new girlfriend.

41. Most people think Cai’s choice          .

A. unbelievable     B. nice                 C. enjoyable      D. wonderful

42. From the passage we know Zhong Haibo          .

A. doesn’t like college life                           B. thinks highly of working as shoe shiners

C. is a middle school student                        D. is still a shoe shiner at the moment