题干

阅读下面的短文,回答问题。

电饭锅中的磁钢限温器

电饭锅是生活中常见的用电器,它是利用感温磁钢(软磁体)的磁性随温度的变化而变化的特性来设计的,这样可以限制煮饭过程中的最高温度。

感温磁钢的磁性随着本身温度作非线性变化,其特性曲线如图甲所示。磁钢限温器结构如图乙所示,它主要由感温磁钢、永磁体和弹簧构成。感温磁钢及其外套、内锅由弹簧支撑。感温磁钢与受热面固定在一起,受热面直接把热量传递给锅底。

煮饭时用手按按钮开关,通过杠杆AOC使永磁体和感温磁钢吸合,在吸力作用下永磁体不会落下,金属触点闭合,电路接通,加热元件开始发热。当饭煮熟后,温度继续上升,当升高到某一温度时,永磁体落下,通过杠杆CBO使触点分开,加热元件停止发热,同时按钮开关跳起。

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同类题4

阅读下面的文章,完成题目
                                                                                                                天机
        厂里最近要进行中层领导竞聘上岗,尽管王林对竞争科长一职充满信心,但心里仍然很不踏实,一连几天,无精打采,郁闷寡欢,就连平时走路也有点直不起腰。
        王林是销售科副科长,正科长马上就要退休了,此次竞聘,王林是众望所归。厂长是新来的,自从上任后,就大刀阔斧地制定了严格的规章制度,然后就在全厂进行“能者上,庸者下”的中层领导竞聘活动,在厂里引起了轩然大波。幸好苍天有眼,王林和厂长办公室门对门,细心的他发现,自从单位此项规定出台以后,厂长的电话,似乎比较频繁和忙碌,到厂长办公室去的人流,明显比往日拥挤了很多。
        王林实在是坐不住了,这些年,他南来北往,为厂里的产品打开销路,立下了汗马功劳,他觉得自己既有知识,又有能力,非常适合这个职位,但没有宣布结果的那一瞬间,任何 事情都是有可能发生的 。见多识广的老父亲语重心长地告诉王林:“孩子,我知道你行。但在这个节骨眼儿上,不去疏通疏通关系,恐怕不行呀。”于是,王林再三思量,狠狠心,咬咬牙,在一个漆黑的夜晚,一辈子从没送过礼的王林,把两千元装进信封,然后揣在怀里,径直去了厂长家里……
        厂长很热情的接待了他,让他受宠若惊,激动万分。双方客套地寒暄了几句,王林吞吞吐吐地说明来意,并怀着忐忑不安的心情,把带着自己体温和全部希望的信封,近乎颤抖地放在厂长的面前;然后,面色绯红地坐在那里,耷拉着脑袋,像霜打的茄子一样。厂长看后,眉头先是一皱,继而微笑着点点头,起身拍拍王林的肩膀,算是应允了此事。
        王林像众人撵贼似地逃出厂长家,他扶在门口的一根电线杆上,拼命地拍打着自己的胸口,大口大口地喘气:“我的娘,谢天谢地,总算收下了。”自己心中悬着的一块石头终于平稳落地。他感到一种从没有过的愉悦和放松,他仿佛知道,自己离科长的位置已经不远了。
        解除了后顾之忧,王林的身板似乎硬了很多。他开始投入全部精力,准备竞选的各项议程。在接下来的中层领导竞选演讲中,王林的演说,饱含了对厂子的深厚感情和对未来的希望。他制定的销售计划思路清晰,层层深入,切实可行,赢得了在场领导和职工们的阵阵掌声。下台的瞬间,王林偷偷看了厂长一眼,也十分佩服老父亲的英明。
        两个月后,王林意外地收到来自本市的一张汇款单,数额为两千元,只见附言栏中写着六个字:“天机不可泄露”。

同类题5

阅读下面短文,从短文后各题所给的四个选项(A、B、C和D)中选出可以填入空白处的最佳选项,并在答题卡上将该项涂黑。

    In winter, I often walk in a nearby park during lunch time. The park is quiet, as 1 people have the time to enjoy the winter sun on a weekday. The two people that are often seen are a middle-aged father and his little daughter 2 her school uniform. The father looks like he has all the time in the world-he 3to hurry along the jogging path; instead he matches his pace with 4of the little girl. Sometimes they are lying 5in the sun, laughing and chatting.

    The man certainly doesn't look6 . What sort of job can he have that gives him the flexibility to walk in the park in the middle of the day?

    And today, we 7 sat on the rocks and had a little chat. “You 8enjoy the park very much to come here so often,” I said. The father nodded. “How” I asked curiously, “do you 9 to leave your office to be with your daughter every day?”

    The story that the father, Satyendra Dugbey, told me showed me how, if we 10 under the surface, even ordinary people's life can be quite 11 .

    “I used to be no different from any of those thousands of office workers 12 to work every day,” he began. His wife and he were well 13 but rarely managed time off for leisure.

    Everything changed after an accident 14 Dugbey was hit by a car. As he lay in hospital, terrifying thoughts 15 his mind. “How would my daughter, then only four, remember me if I died that day?” “Would my daughter have 16 of being with her father?”

    The moment he recovered and went back to work, Dugbey took time off at lunch, 17 her daughter from school which was just next door to his working place, and took her to the park.

    It was actually a very small change he'd made, he said, but it amazed him every day to see the difference it 18 to his life. “It brings me so much 19 that I can't believe why others haven't thought of doing the same thing.” he said simply.

    I got up to continue my 20 walk, unexpectedly happy after his story.