题干

如图所示是某一恒温(需加热)水箱闭环控制电路原理图,图中RT为热敏电阻,其功能是接收水温信息,安装时它是浸在水中,VT1、VT2和R是信号处理电路(控制器),J是继电器,它的开关是电热棒(浸在水中,图中没有画出)的电源开关,RP用来设定温控点。请分析该电路工作原理,完成下列各题,在“ ”处填写上相应内容。

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同类题4

阅读下面短文,根据短文内容,从短文后各题所给的A、B、C、D四个选项中,选择最佳选项。

    The town of Pressure and the town of Pleasure were neighbors but they had nothing in common. Residents(居民) built walls to 1 influence from the other town.

    In Pressure, everyone wanted to be the very best. When women gave birth, they would compete(竞争、比赛) to have the baby with the loudest cry. There was violent competition in every aspect(方面) of life. Because 2 was the symbol(象征) of success. People were always busy making money, with no time for relaxation. Some young people couldn't bear the intensity(紧张) and chose to drink to escape(逃避).

    In Pleasure, the motto(格言) was: If only you like it, do it. People grew up without pressure and could do anything they liked. Children played computer games day and night. At school, teachers didn't care 3 students came or not. Workers might sit around the office all day long drinking coffee and doing 4 .Thanks to the lack(缺乏) of regulations(规章制度), nobody worried about losing their jobs. It was pleasure that mattered. The computers they used were old ones from the town of Pressure.

    Some of the young were addicted(上瘾) to drugs(药物)5 the emptiness(空虚) of their lives. Then, people in the two towns began asking themselves, “What is life 6 ?” But, just before life in the two towns completely7, there came a great person—Mr Reason. He went from door to door, talking with people and 8 advice. People in Pressure learnt to be satisfied with what they had 9 people in Pleasure began to make plans. They 10 the walls between them and built a road to connect the two.